The following are the result, which shows on which system work is done under pressure or not:
1. [tex]NaHCO_{3} (s) + HC_{2} H_{3} O_{2}(aq)[/tex] ⟶ [tex]NaC_{2} H_{3} O_{2} (aq) + H_{2} O(l) + CO_{2} (g)[/tex]
Answer: Work done by the system
2. [tex]2H_{2} O_{2} (g)[/tex] ⟶ [tex]O_{2} (g)[/tex] + [tex]2H_{2} O(g)[/tex]
Answer: No work done
3. [tex]N_{2} (g)[/tex] + [tex]3H_{2} (g)[/tex] ⟶ [tex]2NH_{3} (g)[/tex]
Answer: Work done on the system
4. [tex]H_{2} (g) + F_{2} (g)[/tex]⟶ [tex]2HF(g)[/tex]
Answer: No work done
1. [tex]NaHCO_{3} (s) + HC_{2} H_{3} O_{2}(aq)[/tex] ⟶ [tex]NaC_{2} H_{3} O_{2} (aq) + H_{2} O(l) + CO_{2} (g)[/tex]
An aqueous solution of [tex]NaC_{2} H_{3} O_{3}[/tex], liquid water, and gaseous [tex]CO_{2}[/tex] is created in this reaction between the solid [tex]NaHCO_{3}[/tex] and the liquid [tex]HC_{2} H_{3} O_{2}[/tex]. As the reaction generates a gas, it will expand against the environment and alter it. Therefore, the system does work.
2. [tex]2H_{2} O_{2} (g)[/tex] ⟶ [tex]O_{2} (g)[/tex] + [tex]2H_{2} O(g)[/tex]
In this process, hydrogen peroxide gas is broken down into oxygen gas and water vapour. As this is a gas-phase reaction, neither the system nor its surroundings will significantly expand nor contract. As a result, no work is done.
3. [tex]N_{2} (g)[/tex] + [tex]3H_{2} (g)[/tex] ⟶ [tex]2NH_{3} (g)[/tex]
In this process, nitrogen gas and hydrogen gas are used to create ammonia gas. The reaction will cause the system's volume to drop since the reaction reduces the number of gas molecules from 4 to 2 in the first place. The environment will strive to compress the system. As a result, the system is under construction work done by a system.
4. [tex]H_{2} (g) + F_{2} (g)[/tex]⟶ [tex]2HF(g)[/tex]
In this process, fluorine gas and hydrogen gas are used to create hydrogen fluoride gas. This reaction does not involve any major expansion or compression of the system or its surroundings since the quantity of gas molecules does not change. As a result, no work is done.
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A chemistry student weighs out 0.950 kg of an unknown solid compound X and adds it to 2.00 L of distilled water at 24.° C . After 10 minutes of stirring, only some of the X has dissolved. The student drains off the solution, then washes, dries and weighs the X that did not dissolve. It weighs 0.570 kg.
1) Using the information above, can you calculate the solubility of X?
2) If so, calculate it. Remember to use the correct significant digits and units.
Thanks!
The solubility of X would be S = 190 g/L.
What is meant by solubility?A substance's solubility is the greatest amount that will dissolve in a given amount of solvent at a given temperature. A specific solute-solvent combination's solubility is a defining trait, and the solubilities of various compounds can vary significantly.
The initial mass of the unknown solid exists [tex]$m_i=0.950 \mathrm{~kg}$[/tex]
The mass of the undissolved substance exists [tex]$m_u=0.570 \mathrm{~kg}$[/tex]
The volume of the solution exists V = 2.00 L
1) Yes, it is possible to determine X's solubility since the solubility of a substance in a solution is the quantity of the substance required to saturate 1 unit volume of the solvent solution at the specified temperature.
And from our inquiry, we can see that ingredient X saturates the solvent but is still present in the mixture undissolved.
2) The mass of the substance that dissolved ([tex]m_d[/tex]) is mathematically represented as
[tex]$$\begin{aligned}& m_d=m_i-m_u \\& m_d=0.95-0.570 \\& m_d=0.38 \mathrm{~kg}=0.38 * 1000=380 \mathrm{~g}\end{aligned}$$[/tex]
The solubility of this substance (X) is mathematically represented as
[tex]$S=\frac{m_d}{V}$$[/tex]
substituting values in the above equation, we get
[tex]$$\begin{aligned}& S=\frac{380}{2} \\& S=190 \mathrm{~g} / \mathrm{L}\end{aligned}$$[/tex]
Therefore, the solubility of X would be S = 190 g/L.
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Which of the following was Robert A. Millikan able to determine, either from his own work, or by building on the work of J.J. Thomson? Select all that apply. Select all that apply: 0 The existence of an electron The charge of an electron The mass of an electron The model of an atom with a small, positively charged nucleus.
Robert A. Millikan able to determine, either from his own work, The mass of an electron. Hence, the correct option is (c).
Robert A. Millikan was able to determine the charge of an electron, but the discovery of the electron itself was made by J.J. Thomson. Millikan's work built on Thomson's discovery and helped to refine our understanding of the properties of electrons. By conducting the oil drop experiment, Millikan was able to measure the charge of an electron with great precision. He observed the motion of tiny oil droplets that were suspended in an electric field, and by measuring the strength of the electric field and the speed of the droplets, he was able to calculate the charge of each droplet. By adjusting the strength of the electric field, he was able to find the smallest possible charge that a droplet could have, which corresponded to the charge of a single electron. However, Millikan did not determine the mass of an electron, as this was already known from Thomson's work on the charge-to-mass ratio of electrons. Additionally, Millikan did not propose a model of an atom with a small, positively charged nucleus, as this idea was developed later by Ernest Rutherford.
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use the ph scale below to determine the ph value of the water in this test. record the value. also, determine whether the ph stayed the same, became more acidic, or became more alkaline compared to the first test.
The pH value of the water decreased: indicating that it became more acidic compared to the first test.
During the experiment, the student blew bubbles into the water, which introduced carbon dioxide. Carbon dioxide reacts with water to form carbonic acid, a weak acid that can lower the pH of the water. As a result: the pH value of the water decreased, indicating that it became more acidic.
This is because the concentration of hydrogen ions, which determine acidity, increased in the water. The change in pH value may have implications for the organisms living in the water, as different pH levels can affect their survival and growth. Therefore understanding the effects of human activities, such as blowing bubbles into water, on pH levels is important for maintaining the health of aquatic ecosystems.
This question should be given as:
A student placed a straw into the water and blew bubbles (carbon dioxide) into the water for 30 seconds. The pH of the glass of tested again. Use the pH scale below to determine the pH value of the water in this test. Record the value. Also, determine whether the pH stayed the same, became more acidic, or became more alkaline compared to the first test.Learn more about alkaline brainly.com/question/27006881
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a 2.0 l sample of butane at 25 c and 1.3 atm is combusted with excess o2. using the bond enthalpies given above, estimate the change in energy by this sample of butane (c4h10). chemical structure of butane:
The chemical equation for the combustion of butane (C4H10) with excess oxygen (O2) is:
C4H10 + 13/2 O2 → 4 CO2 + 5 H2O
The balanced equation shows that 1 mole of butane reacts with 13/2 moles of O2 to produce 4 moles of CO2 and 5 moles of H2O. The change in energy for the combustion of butane can be calculated using bond enthalpies, which are given in units of kJ/mol of bonds broken or formed.
The bond enthalpies needed for this calculation are:
C-H = 413 kJ/mol
C-C = 348 kJ/mol
C=O = 799 kJ/mol
O=O = 498 kJ/mol
O-H = 463 kJ/mol
First, we need to calculate the total energy required to break the bonds in butane:
4 C-H bonds × 413 kJ/mol/bond = 1652 kJ/mol
8 C-C bonds × 348 kJ/mol/bond = 2784 kJ/mol
The total energy required to break the bonds in butane is:
1652 kJ/mol + 2784 kJ/mol = 4436 kJ/mol
Next, we need to calculate the total energy released by forming new bonds in the products:
8 C=O bonds × 799 kJ/mol/bond = 6392 kJ/mol
10 O-H bonds × 463 kJ/mol/bond = 4630 kJ/mol
The total energy released by forming new bonds in the products is:
6392 kJ/mol + 4630 kJ/mol = 11022 kJ/mol
The net change in energy for the combustion of butane is:
11022 kJ/mol - 4436 kJ/mol = 6586 kJ/mol
Finally, we need to calculate the energy change for the given sample of butane (C4H10) by using the Ideal Gas Law:
PV = nRT
where P = 1.3 atm, V = 2.0 L, n is the number of moles of butane, R is the gas constant (0.0821 L·atm/mol·K), and T = 25°C = 298 K.
Solving for n, we get:
n = PV/RT = (1.3 atm)(2.0 L)/(0.0821 L·atm/mol·K)(298 K) = 0.108 mol
Therefore, the change in energy for the given sample of butane (C4H10) is:
6586 kJ/mol × 0.108 mol = 711 kJ
Therefore, the change in energy for the given sample of butane (C4H10) is approximately 711 kJ.
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. Why do you need to fill the bomb with pure oxygen? What would happen if you skipped that step and just allowed the bomb to fill with air?
To calculate the heating value of both solid and liquid fuels, one uses a bomb calorimeter. It is made up of a powerful steel shell called a bomb. It is composed of a base that holds the platinum cross.
What exactly is a solid defined as?
It seems evident what a solid is; a solid is typically thought of as hard and firm. However, closer examination makes the term less clear. For instance, a butter cube is unmistakably a solid since it becomes hard after being kept in a refrigerator. Having stayed on the
A crystalline solid is what?
A solid that has its component atoms and molecules (or occasionally ions) arranged in a crystalline structure microscopic structure is referred to as a crystal lattice (also referred as a crystal). A homogeneous microscopic structure known as a crystal lattice extends across every point of the crystalline solid.
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carbohydrates serve as a vital source of chemical energy to the human body. carbohydrates are broken down into smaller units of glucose, among other sugars, providing energy to various muscles and orgnas, including the brain. on average, for every 15.0g of carbohydrates consumed, the body will store 250kj of energy.convert this energy value to kilocalories (kcal).
The energy value to kilocalories (kcal) would be 32.5 kcal.
What is the difference between energy value and kilocalories?One kilogram of water requires one kilocalorie (1 kcal, or 1000 calories) of heat energy to raise its temperature by one degree Celsius (°C). Joule is the SI-standard unit for energy (J). About 4.18 calories make up one kcal.
The phrase used to describe how much energy is needed to raise a liter of water's temperature by one degree Celsius at sea level. The term "calorie" is frequently used in nutrition terminology to describe a unit of dietary energy.
Let the equation be
1 kJ = 1,000 J
1 cal = 4.184 J
1 kcal = 1,000 cal
136 kj x 1000j/1kj = 1.36 x [tex]$$10^5[/tex] J
simplifying the equation, we get
1.36 x [tex]$$10^5[/tex] J x 1 cal/4.184J = 32, 500
32500 cal x 1 kcal/1,000 cal = 32.5 kcal.
Therefore, the energy value to kilocalories (kcal) would be 32.5 kcal.
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Use the Text Submission box to answer the following question. Rank the following bonds in order of strength from weakest to strongest:
a. C-C
b. C=C
c. C-H
d. C-O
e. C=O
f. C-F
g. C-Br
h. C≡N
The strength of a bond between two atoms is determined by the amount of energy required to break the bond.
The higher the bond energy, the stronger the bond. Generally, the more bonds between two atoms, the stronger the bond.
Based on this information, we can rank the bonds in order of strength from weakest to strongest:
Therefore, the bond between C and Br is the weakest, while the bond between C and N with a triple bond is the strongest.
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cjhegg q12: which region of earth generally has the highest concentration of water vapor and which region generally has the lowest concentration? q13: why would the distribution of water vapor change across the globe in the way that you identified in q13? (i.e., why would the region that had the highest concentration be expected to have the highest concentration and why would the region that had the lowest concentration be expected to have lowest concentration?) q14: how would you describe the movement of the area with the most water vapor over the course of a year? q15: how does the movement you just described relate to what you learned in the solar radiation
The tropical regions of earth contains the highest concentration of water vapor and higher altitudes and poles have the lower water vapor concentration.
What is differential distribution of water vapor ?Lower atmospheric water vapor molecules absorb heat generated from the Earth's surface. In turn, the water vapor molecules emit heat in all directions. The Earth's surface receives some of the heat back.
In the tropics, as the seasons change, a band of extremely humid air sways both north and south of the equator. The Intertropical Convergence Zone, where the easterly trade winds from either hemisphere meet and create almost daily thunderstorms and clouds, includes this ring of dampness.
Water vapor concentrations are higher farther from the equator in the summer-experienced hemisphere and lower in the winter-experienced one.
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how many kinds of chemically non-equivalent hydrogens are there in each of the following compounds? xyxlohexane n-ch3
The number of the chemically non-equivalent hydrogens are there in the cyclohexane and N - (CH₃)₃ is zero.
The Non-equivalent hydrogen are groups of the hydrogens will have different synthetic movements. The Symmetry is the main component to determine the non-equivalent hydrogens.
The all the hydrogens in the cyclohexane are chemically equivalent hydrogens , therefore the is zero non equivalent hydrogen. In the compound N - (CH₃)₃ that is the N,N-Dimethylmethanamine. The non - equivalent hydrogen in this compound is zero because all the hydrogen are chemically equivalent. Therefore , all the hydrogens in the cyclohexane and N - (CH₃)₃ are chemically equivalent.
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cherise the chemist needs to make 750.0 ml of 2.00 m h3po4 solution. she has 14.8 m (concentrated) h3po4 solution available. select the correct choices from the drop-down menus to describe how she should make this solution. combine ______of 14.8 m h3po4 with _____distilled water to make 750.0 ml of 2.00 m h3po4 solution.
The molarity of the stoke solution is 14.8 M. Then we need 101.35 ml of the stoke solution with 648.65 ml of distilled water to make 750.0 ml of 2.00 M H₃PO₄ solution.
What is molarity ?Molarity is a common term used to express the concentration of a solution. It is the ratio of number of moles of solute to the volume of solution in liters.
If we have a stoke solution of molarity M1 and volume V1, and the solution prepared from the stoke solution is having molarity M2 and volume V2, then,
M1 V1 = M2 V2.
Given, M1 for the stoke acid solution = 14.8 M
M2 = 2 M
V2 = 750 ml.
then V1 = M2 V2/V1
V1 = 750 ml × 2 M /14.8 M= 101.35 ml.
water to be added to 750 ml = 750 - 101.35 = 648.65 ml
Therefore, you have to combine 101.35 ml of 14.8 M H₃PO₄ with 648.65 ml distilled water to make 750 ml of 2 M solution.
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A saturated aqueous solution of CdF2 is prepared. The equilibrium in the solution is represented above. In the solution, [Cd2+]eq=0.0585M and [F−]eq=0.117M. Some 0.90MNaF is added to the saturated solution. Which of the following identifies the molar solubility of CdF2 in pure water and explains the effect that the addition of NaF has on this solubility?
CdF2(s)⇄Cd2+(aq)+2F−(aq)
The molar solubility of CdF₂ in pure water is 0.0585M, and adding NaF decreases this solubility because the equilibrium shifts to favor the precipitation of some CdF₂. The correct option is A.
According to the statement, the option that identifies the molar solubility of CdF₂ in pure water and explains the effect that the addition of NaF has on this solubility is [CdF₂]eq = [Cd₂+]eq = 0.0585 M (since the solubility product expression for CdF₂ gives Ksp = [Cd₂+][F-]², and F- is in excess).
The molar solubility of CdF₂ in pure water can be determined by calculating the concentration of Cd₂+ and F− ions in the saturated solution, and then using the stoichiometry of the equilibrium reaction to determine the concentration of CdF₂ that would dissolve in pure water.
From the equilibrium equation: CdF₂(s) ⇄ Cd₂+(aq) + 2F−(aq), we know that for every mole of CdF₂ that dissolves, 1 mole of Cd₂+ and 2 moles of F− ions are produced.
The effect of adding NaF to the saturated solution can be explained by the common ion effect. When NaF is added, it provides additional F− ions, which are already present in the saturated solution, and thus increases the concentration of the common ion.
This leads to a shift in the equilibrium to the left, causing more CdF₂ to precipitate out of solution until a new equilibrium is established. As a result, the molar solubility of CdF₂ in the solution decreases.
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Complete question:
CdF₂(s)⇄Cd₂+(aq)+2F−(aq) A saturated aqueous solution of CdF₂ is prepared. The equilibrium in the solution is represented above. In the solution, [Cd₂+]eq=0.0585M and [F−]eq=0.117M. Some 0.90MNaF is added to the saturated solution. Which of the following identifies the molar solubility of CdF₂ in pure water and explains the effect that the addition of NaF has on this solubility?
a. The molar solubility of CdF₂ in pure water is 0.0585M, and adding NaF decreases this solubility because the equilibrium shifts to favor the precipitation of some CdF₂.
b. The molar solubility of CdF₂ in pure water is 0.0585M, and adding NaF has no effect on the solubility because only changes in temperature can increase or decrease the molar solubility of an ionic solid.
c.The molar solubility of CdF₂ in pure water is 0.117M, and adding NaF decreases this solubility because the equilibrium shifts to favor the precipitation of some CdF₂.
d. The molar solubility of CdF₂ in pure water is 0.176M, and adding NaF increases this solubility because the Na+ ions displace the Cd₂+ ions, causing the equilibrium to shift to favor the products.
Identify these elements based on their locations in the periodic table. Give the symbol, not the name.
period 5, group 2 (2A)___________
period 4, group 11 (1B)____________
period 6, group 15 (5A)________________
The symbol and the names are:
Period 5, group 2 (2A) - Strontium (Sr)Period 4, group 11 (1B) - Copper (Cu)Period 6, group 15 (5A) - Antimony (Sb)What is a periodic table?
This refers to a table that organizes all discovered chemical elements in rows (called periods) and columns (called groups) according to increasing atomic number.
The periodic table of elements puts all the known elements into groups with similar properties. This makes it an important tool for chemists, nanotechnologists and other scientists. An understanding of the periodic table helps a scientist predict how a chemical element behaves.
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true/false. in general, the bonding within some materials may not be predicted by the ketelaar triangle. for example, it only accounts for the primary bonding types (metallic, ionic, and covalent).
The given statement: "in general, the bonding within some materials may not be predicted by the Ketelaar triangle. for example, it only accounts for the primary bonding types (metallic, ionic, and covalent)", is true (T) because the Ketelaar triangle indeed only accounts for the primary bonding types and does not consider other bonding types that may exist in some materials.
The Ketelaar triangle is a useful tool for predicting the types of bonding that may occur in a material based on its electronegativity difference. However, it only considers the three primary bonding types: metallic, ionic and covalent. There are other types of bonding, such as hydrogen bonding and van der Waals forces, that may also be present in some materials.
These types of bonding are not accounted for by the Ketelaar triangle, so its predictions may not always be accurate. Therefore while the Ketelaar triangle is a helpful starting point for understanding bonding in materials, it should not be relied upon as the only tool for predicting bonding behavior.
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The modern penny has a mass of 2.500 g when it is manufactured, but it is mostly zinc metal. Only the outside of the penny is coated in copper. Each modern penny is coated in 0.0625 g of copper. how many atoms of copper (Cu) are in a modern penny?
If the modern penny has a mass of 2.500 g when it is manufactured, but it is mostly zinc metal. The number of atoms of copper (Cu) that are in a modern penny is: 5.91 x 10^18 atoms of copper (Cu).
How to find the number of atoms of copper?To calculate the number of atoms of copper (Cu) in a modern penny, we need to know the atomic mass of copper, which is 63.55 g/mol, and the Avogadro's number, which is 6.022 x 10^23 atoms/mol.
First, we'll calculate the number of moles of copper in the penny by dividing its mass by the atomic mass of copper:
0.0625 g / 63.55 g/mol = 9.84 x 10^-5 mol
Next, we'll multiply the number of moles by Avogadro's number to get the number of atoms:
9.84 x 10^-5 mol * 6.022 x 10^23 atoms/mol = 5.91 x 10^18 atoms
Therefore, there are approximately 5.91 x 10^18 atoms of copper (Cu) in a modern penny.
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three resonance structures are possible for the cation shown. one resonance form is given. draw the two remaining resonance structures (in any order), including nonbonding electrons and formal charges. omit curved arrows. resonance structure a is a 6 carbon chain where carbon 1 has a carbocation, there is a double bond between carbons 2 and 3 and between carbons 4 and 5 and carbon 5 has a methyl substituent. structure b structure c which structure contributes most to the hybrid? the primary allylic carbocation is the major resonance structure. the tertiary allylic carbocation is the major resonance structure all structures are equal contributors. the secondary allylic carbocation is the major resonance structure
In the figure below, the incomplete resonance structure that is lacking is attached. The addition of the nonbonding electrons and their formal charge, which can be seen from there, completes the resonance structure.
What is a resonance structure?Resonance, also known as mesomerism, is a method used in chemistry to describe bonding in specific molecules or polyatomic ions by combining numerous contributing structures into a resonance hybrid according to the valence bond theory. The electronic bonding, including fractional bonds and fractional charges, of a single polyatomic species is collectively represented by resonance structures, which are a collection of two or more Lewis structures. The number of electrons in resonance structures should be constant; do not add or subtract any electrons. (Count the electrons to determine their number). Every resonance structure complies with the standards for writing Lewis Structures. The structure's hybridization must continue to be the sameIn the figure, the other two resonance structures that can be obtained from the entire structure are also depicted. The hybrid is primarily made up of the structure with the negative charge on the oxygen among these three structures.To learn more about resonance structure, refer to:
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which of these variables are not state functions? which of these variables are not state functions? m (mass) u (internal energy) q (heat) t (temperature) w (work) v (volume)
The variables that are not state functions are m (mass), q (heat), and w (work).
What is work?Work is an activity that requires physical or mental effort and is done in exchange for money or other rewards. It can also be seen as an exchange of energy, where an individual puts in effort in order to achieve a desired outcome. Work can be done in a variety of fields and can range from manual labor to professional jobs. It is an important part of many people's lives and can be a source of fulfillment and satisfaction, as well as providing a means of economic security. Work can also be a source of stress, but when done properly can be a great way to make a living, develop skills, and better oneself.
Therefore, The variables that are not state functions are m (mass), q (heat), and w (work).
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If 38g of water are produced in the reaction, how many moles of COz were produced.
If 38g of water are produced in the reaction, 19 moles of CO₂ were produced.
What is mole ?The term mole is defined as the amount of substance of a system which contains as many elementary entities.
One mole of any substance is equal to 6.023 × 10²³ units of that substance such as atoms, molecules, or ions. The number 6.023 × 10²³ is called as Avogadro's number or Avogadro's constant.
CO₂ + 4H₂ → CH₄ + 2H₂O
In the above reaction we see that,
2 mole of H₂O produce 1 mol of CO₂
Therefore,
38 gram of H₂O produce 19gram of CO₂
Thus, If 38g of water are produced in the reaction, 19 moles of CO₂ were produced.
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using a reference table, determine the hrxn for each of the three reactions you performed from the heats of formation of each of the species in the reaction.
The enthalpy change of a reaction (ΔHrxn) can be calculated using the heats of formation of each of the reactants and products.
The heat of formation (ΔHf) is the enthalpy change that occurs when one mole of a compound is formed from its constituent elements in their standard states under standard conditions. The standard state is the most stable form of the element at a given temperature and pressure.
The equation for calculating the enthalpy change of a reaction using heats of formation is:
ΔHrxn = Σ(nΔHf(products)) - Σ(nΔHf(reactants))
Where ΔHf is the heat of formation, n is the stoichiometric coefficient, and Σ is the sum of the heats of formation for all species in the reaction.
By using a reference table of heats of formation, we can calculate the enthalpy change for a given reaction and determine if it is exothermic (ΔHrxn < 0) or endothermic (ΔHrxn > 0).
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In a calorimeter, the temperature of 100 g of water decreased by 20°C when 10 g of ice melted. How much heat was absorbed by the ice?
A 8.36 j
b 8.36 kj
c 20 kj
d 836 kj
The heat that is absorbed is 8.36 kj.
What is the heat that is absorbed?Heat absorbed by ice is the amount of thermal energy that is transferred from its surroundings to the ice, causing the temperature of the ice to increase. This process occurs until the ice reaches its melting point, at which point it begins to convert from a solid state to a liquid state.
We have that;
Q = mcdT
Q = Heat absorbed
m = mass of the substance
c = Heat capacity
dT = temperature change
Thus
Q = 100 * 4.18 * (20)
Q = 8.36 kj
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if q > keq, what does that say about the relationship of the system to equilibrium? group of answer choices A. the system is not at equilibrium and will produce more reactants to reach equilibrium (shift to the left). B. the system is at equilibrium. C. the system is not at equilibrium and will produce more products to reach equilibrium (shift to the right). D. there is no relationship between q and keq.
If q > Keq, it means that the reaction quotient, q, has a higher numerical value than the equilibrium constant, Keq and the system is not at equilibrium and will produce more reactants to reach equilibrium (shift to the left).
Therefore, the system is not at equilibrium and will shift in the direction that reduces the value of q and increases the value of Keq, which is toward the side of the reaction with fewer products and more reactants.
In this case, the system will shift to the left (produce more reactants) to reach equilibrium. This suggests that there is an excess of products or a deficiency of reactants in the system compared to what would be present at equilibrium.
Hence the correct option is A.
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In this experiment, we will need to ensure the sample and burette are ready for titration. Select ALL the statements that are TRUE. Note: Partial credit will not be given to partial answers. You must select ALL the true statements. Right before titration, add 5-8 drops of the indicator, Calmagite. Measure the pH of the water solution and adjust it to pH 7 with HCI. Measure the pH of the water solution and adjust it to pH 10 or above with a buffer. Rinse and coat with DI water, then with EDTA solution before filling it up with EDTA. Right before titration, add 5-8 drops of the indicator, phenolphthalein.
Prior to titration, the buret must be cleaned with lab water and the titration solution. With little volumes of lab water, rinse the buret three times.
What is meant by Calmagite?A complex metric indicator called calmagite is used in analytical chemistry to detect the presence of metal ions in solution. The color of calmagite changes when it is attached to an ion, just like with other metal ion indicators. The titration of calcium or magnesium with ethylenediaminetetraacetic acid frequently uses the indicator calmagite in analytical chemistry (EDTA). The amount of magnesium in biological materials can be determined using it as well. water soluble.In the presence of calcium (Ca 2+) and magnesium (Mg 2+) ions at pH 10, the metal ion indicator calmagite causes a solution to turn wine red. When EDTA is added to a solution, the indicator is removed from the metal-indicator complex and the solution turns blue.To learn more about Calmagite, refer to:
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water is the working fluid in an ideal rankine cycle power plant. superheated vapor enters the turbine at 10 mpa, 4800c, and the condenser pressure is 6 kpa. the cooling water used in the power plant entered the condenser at 200c and exited at 350c. to gain understanding, we performed the following calculations: (a) work done by the turbine per kg of water (b) work consumed by the pump per kg of water (c) heat input in the steam generator per kg of water (d) heat rejected at the condenser per kg of water (e) the efficiency of the power plant (f) the mass flow rate of water in the cycle and the mass flow rate of cooling water assuming a 4000 mw power plant, i.e. similar to the palo verde nuclear power plant in arizona (g) how much is the mass flow rate of cooling water compared to the residential water use of a person in us (100 gallons of water per day
The calculations listed provide a comprehensive understanding of the thermodynamic performance of the Rankine cycle power plant and the water requirements of the plant.
This is a thermodynamics problem involving an ideal Rankine cycle power plant that uses water as its working fluid. The problem requires the calculation of various parameters, including the work done by the turbine, work consumed by the pump, heat input, heat rejected, efficiency, and mass flow rates of water and cooling water.
The problem also requires a comparison of the mass flow rate of cooling water to the residential water use of a person in the US. The solution to this problem involves applying the principles of thermodynamics, specifically the Rankine cycle, and using relevant equations to calculate the required parameters.
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Explain why the Jobs method works in determining the formula of a salt.
The Jobs method works because the ratio of the cations to the anions in a salt is fixed and can be determined by measuring the mass of the precipitate formed when the salt is reacted with a known quantity of a reagent.
What is Job?
In the context of chemistry, the "Jobs method" refers to a chemical technique used to determine the empirical formula of a salt. It is named after its inventor, Zdenko Hans Skraup Job (1865-1933), who was an Austrian chemist and professor of chemistry at the University of Prague.
Job is best known for his work on the synthesis and properties of organic compounds, particularly his research on indole derivatives and alkaloids. He also made important contributions to the field of physical chemistry, including the development of the Jobs method for determining the empirical formula of a salt.
The Jobs method is a chemical technique used to determine the empirical formula of a salt. It involves finding the ratio of the cations and anions in the salt by taking advantage of the precipitation reaction that occurs between the salt and a known amount of a reagent that forms an insoluble product with one of the ions in the salt.
The general steps of the Jobs method are as follows:
A known quantity of the salt is dissolved in water to form a solution.
A known quantity of a reagent is added to the solution, which reacts with one of the ions in the salt to form an insoluble precipitate.
The precipitate is filtered and dried, and the mass is measured.
The mass of the precipitate is used to calculate the moles of the ion that reacted with the reagent.
The ratio of the moles of the cation to the moles of the anion is calculated.
The ratio is then simplified to the smallest whole number ratio to determine the empirical formula of the salt.
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TASK 2 - Pass 2B.P4 Identify an alkene and carboxylic acid using primary observations. To achieve 2B.P4, learners should follow guidance to identify an alkene and a carboxylic acid (for example, ethanoic acid) from primary observations. Learners will be expected to identify an alkene in the way described in 1B.4. For ethanoic acid this is by its pH and its reaction with sodium carbonate. The guidance given to the learners could be in the form of a flowchart.
Carboxylic acids are acidic due to the presence of the carboxyl group. They can react with bases to form salts and water. Alkenes, on the other hand, are not acidic.
How can you distinguish the alkene from the carboxylic acid?Alkenes have a carbon-carbon double bond (-C=C-), while carboxylic acids have a carboxyl group (-COOH). You can identify the functional group by looking at the molecular formula or by using spectroscopic techniques like infrared (IR) spectroscopy.
Carboxylic acids have higher boiling points than alkenes due to the presence of hydrogen bonding between carboxylic acid molecules.
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calculate the number of moles in 2.3gram of sodium (Na=23).
The number of moles in 2.3 grams of sodium atom is 0.1 moles and is calculated by formula, mass/molar mass.
What is a mole?Mole is defined as the unit of amount of substance . It is the quantity measure of amount of substance of how many elementary particles are present in a given substance.
It is defined as exactly 6.022×10²³ elementary entities. The elementary entity can be a molecule, atom ion depending on the type of substance. Amount of elementary entities in a mole is called as Avogadro's number.It is given as,mass/molar mass= 2.3/23=0.1 moles
Thus, there are 0.1 moles in 2.3 grams of sodium.
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for the reaction between sodium metal and water, determine how many grams of hydrogen gas will form if you start with 4.0 moles of sodium. assume you have more than enough water.
If you start with 4.0 moles of sodium, 4.0 moles of hydrogen gas will form.
The balanced chemical equation for the reaction between sodium metal and water is [tex]2N_a + 2 H2_O[/tex] - > [tex]2 NaOH + H2.[/tex] The stoichiometry of the equation indicates that 2 moles of sodium reacts with 1 mole of water to produce 1 mole of hydrogen gas.
Therefore, if you start with 4.0 moles of sodium, all of it will react with water to produce 2.0 moles of hydrogen gas. To convert moles to grams, you would need to use the molar mass of hydrogen, which is 1.008 g/mol, giving a final answer of 2.016 grams of hydrogen gas.
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A recipe calls for -cup of butter. One ounce (oz) of butter is equivalent to 2 tablespoons (T) and 4 there are 8 oz of butter in 1 cup. Which of the following statements correctly interpret the information provided? Select all that apply. Check all that apply. O The information provided gives the conversion factor 8 oz /2 TO The information provided gives the conversion factor 8 oz/1 cupO The recipe requires 64 T of butter. O The recipe requires 4T of butter.
The statements that correctly interpret the information provided, about the recipe are The information provided gives the conversion factor 8 oz /2 T, and The recipe calls for 4T of butter. The correct A and D.
Using this information, we can convert the amount of butter needed in the recipe from cups to tablespoons. Since there are 8 oz of butter in 1 cup, and 1 oz is equivalent to 2 T, we can calculate that 1 cup of butter is equivalent to 16 tablespoons (8 oz x 2 T/oz = 16 T). Therefore, if the recipe calls for -cup of butter, this is equivalent to 8 tablespoons of butter (1/2 cup x 16 T/cup = 8 T).
Additionally, we can check that 1/4 cup of butter is equivalent to 4 tablespoons by using the conversion factor of 8 oz / 1 cup. Since 1/4 cup is one-fourth of 1 cup, it is equivalent to 2 oz of butter (8 oz / 4 = 2 oz). Then, using the conversion factor of 1 oz = 2 T, we can calculate that 2 oz of butter is equivalent to 4 tablespoons (2 oz x 2 T/oz = 4 T).
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The electron is moving from
energy level 2 to energy
level 1 (the ground state).
What happens during this
transition?
A. The electron falls into the nucleus.
B. The electron creates an absorption line (black line) on
a spectrum.
C. The electron emits a photon of EMR.
D. The electron absorbs a photon of electromagnetic
radiation (EMR).
The electron is moving from energy level 2 to energy level 1 the ground state then the electron emits a photon of EMR. Therefore, option C is correct.
What is energy level ?The set distances from an atom's nucleus where electrons may be found are referred to as energy levels. In an atom, the small, negatively charged electrons orbit the central, positively charged nucleus.
The energy of the electron drops when it changes levels, and the atom releases photons. The emission of the photon occurs as the electron transitions from a higher to a lower energy state.
Thus, option C is correct.
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How many oxygen formula units are in 85 grams are in (insert pic formula)? MM=601.93
50 POINTS!!!!!!!!
There are 6.7 * 10^23 oxygen atoms
What is the mole?The mole is a unit of measurement in chemistry used to express amounts of a chemical substance. One mole is defined as the amount of a substance that contains Avogadro's number of entities, which is approximately 6.022 x 10^23 entities
The first step is to get the number of moles of the compound.
Number of moles =85 grams/602 g/mol
= 0.14 moles
Then we have the number of oxygen atoms as;
0.14 moles * 8 * 6.02 * 10^23
= 6.7 * 10^23 oxygen atoms
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Relate how the energy of ATP hydrolysis can be harnessed to drive an energetically unfavorable condensation reaction.(A-H + B-OH → A-B + H2O)
ATP hydrolysis releases energy in the form of a high-energy phosphate bond.
This energy can be harnessed to drive energetically unfavorable condensation reactions, such as the reaction A-H + B-OH → A-B + H2O. In this reaction, a covalent bond is formed between A and B, while a water molecule is released.
The overall reaction can be written as:
B-OH + ATP → B-PO4 + ADP (phosphorylation of B)
B-PO4 + A-H → A-B + H2O + Pi (condensation reaction)
The overall reaction is exergonic, as it involves the release of energy from the hydrolysis of ATP, which is coupled to the energetically unfavorable condensation reaction.
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