Moles of C are in 86.g is 7.16 The correct answer is C. 7.16 mol.
To determine the number of moles of carbon (C) in 86.0 g of carbon, we need to use the concept of molar mass. The molar mass of an element is the mass of one mole of that element. In this case, the molar mass of carbon is 12.01 g/mol.
To convert the mass of carbon to moles, we can use the following equation:
moles = mass (g) / molar mass (g/mol)
Let's plug in the values:
moles of C = 86.0 g / 12.01 g/mol
Calculating this expression, we get:
moles of C ≈ 7.16 mol
Therefore, the correct answer is C. 7.16 mol.
The molar mass of carbon is determined by adding up the atomic masses of its constituent atoms, which in this case is 12.01 g/mol. When we divide the given mass of 86.0 g by the molar mass, we obtain the number of moles.
It is important to note that the molar mass of carbon is a fundamental constant derived from experimental data. It allows chemists to relate the mass of a sample to the number of atoms or molecules present in that sample. By utilizing the concept of moles, scientists can perform calculations and conversions to analyze and understand chemical reactions and compositions.
Therefore, in the given sample of 86.0 g of carbon, there are approximately 7.16 moles of carbon present. Option C
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Lidocaine is available in an ampule with 100 mg in 5 ml of solution. how many ml do you give to administer 65 mg?
Lidocaine is available in an ampule with 100 mg in 5 ml of solution. We need to give 3.25ml to administer 65mg.
Lidocaine is an anesthetic that has the power to neutralize neuromal membranes.
Given data:
Amount desired (D) = 65 g
Amount on hand (H) = 100 mg
Quantity = 5 mL
Plug in what you know into the formula and simplify.
[tex]\frac{Amount desired}{Amount in hand}[/tex] × quantity
[tex]\frac{65}{100}[/tex] × 5
0.65 × 5 = 3.25ml
Therefore, When Lidocaine is available in an ampule with 100 mg in 5 ml of solution. We need to give 3.25ml to administer 65mg.
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A liquid solvent is added to a flask containing an insoluble solid. the total volume of the solid and liquid together is 81.0 ml. the liquid solvent has a mass of 40.5 g and a density of 0.865 g/ml. determine the mass of the solid given its density is 2.25 g/ml.
The mass of solid is 76.905 g.
Given that,
Total volume of solid and liquid = 81.0 mL
Mass of liquid = 40.5 g
Density of liquid = 0.865 g/mL
Density of solid = 2..25 g/mL
We need to calculate the volume of liquid
Using formula of density
[tex]Density = Mass/volume(V_{l} } )\\\\volume(V_{l} )=Mass/Density[/tex]
Put the value into the formula
[tex]V_{l} = 40.5/0.865\\\\V_{l} = 46.82 mL[/tex]
We need to calculate the volume of solid
Volume of solid = Total volume of solid and liquid- volume of liquid
[tex]V_{s} =81.0-46.82\\\\V_{s} =34.18 mL[/tex]
We need to calculate the mass of solid
[tex]P_{s}=M_{s} /V_{s} \\\\M_{s} =P_{s}V_{s}[/tex]
Using formula of density
Put the value into the formula
[tex]M_{s}=2.25 X 34.18\\\\M_{s}=76.905 g[/tex]
Hence, The mass of solid is 76.905 g.
What is density?A substance's density (more accurately, its volumetric mass density; sometimes known as specific mass) is its mass per unit volume. The most common symbol for density is (the lower case Greek letter rho).
There are three types of Density:
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Help!!
Classify each diagram as an element a compound or mixture
Answer:
1. Mixture
2. Compound
3. Compound
4. Element
Explanation:
Number 1 shows two completely different types of compounds in the same space, so it is a mixture.
Numbers 2 and 3 are compounds because there aren't different types compounds as in Number 1, but the same compound repeated. 2 is a compound because while all of the circles are the same element, they are connected. O2 for example, oxygen, is a compound.
Number 4, finally, is all of the same substance, non-connected, so it shows an element.
Brainliest, please :) (Trying to become a genius so that I can continue helping more people)
There are millions of organic compounds but only thousands of inorganic compounds because:______
Answer:
There are millions of organic compounds but only thousands of inorganic compounds because:
a. organic compounds were formed by living things.
b. there is more carbon on Earth's surface than any other element.
c. atoms of elements other than carbon never combine with themselves.
d. carbon atoms can combine with up to four other atoms, including other carbon atoms.
How many moles of helium are in a
45.0 liter tank at 293 K and 15.0 atm?
Answer:
28.1 moles (three sig digits)
Explanation:
Using Ideal Gas Law
PV = n RT looking for 'n' R = .082057366 L-atm/K-mole
15.0 * 45.0 = n * .082057366 * 293
n = 28.1 Moles
The number of moles of helium that are in a 45.0-liter tank at 293 K and 15.0 atm is 28.1 Moles.
What are moles?Moles is the measuring unit that measures the quantity of a substance. Moles is a SI unit.
Helium is the lightest gas, which is used in the tires of an airplane if it is filled in the balloons, the balloon flies in the sky.
Given the volume is 45.0 liter
The pressure is 15.0 atm.
The temperature is 293 K
To calculate the moles, we will use the formula of an ideal gas:
PV = n RT
R = .082057366 is the gas constant.
We have to calculate the n
Putting the values in the equation
15.0 x 45.0 = n x .082057366 x 293
n = 28.1 Moles.
Thus, the moles of helium is n = 28.1 Moles.
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The main constituent of gallstones is cholesterol. Cholesterol may have a role in heart attacks and blood clot formation. Its elemental percentage composition is 83.87% C, 11.99% H, and 4.14% O. It has a molecular weight of 386.64 amu. Calculate its empirical and molecular formulas.
The main constituent of gallstones is cholesterol. Cholesterol may have a role in heart attacks and blood clot formation. Its elemental percentage composition is 83.87% C, 11.99% H, and 4.14% O. It has a molecular weight of 386.64 amu. Empirical formula is C₃H₄O₁ and Molecular formula is 7(C₃H₄O₁).
What is Empirical Formula ?Empirical formula is the simplest whole number ratio of atoms present in given compound.
Element % Atomic mass Relative no. of atoms Simplest whole ratio
C 83.87 12 [tex]\frac{83.87}{12}[/tex] = 6.98 [tex]\frac{6.98}{0.25}[/tex] = 3
H 11.99 1 [tex]\frac{11.99}{1}[/tex] = 11.09 [tex]\frac{11.09}{0.25}[/tex] = 4
O 4.14 16 [tex]\frac{4.14}{16}[/tex] = 0.25 [tex]\frac{0.25}{0.25}[/tex] = 1
Thus the empirical formula is C₃H₄O₁.
How to find the Molecular formula of compound ?Molecular formula = Empirical formula × n
n = [tex]\frac{\text{Molecular weight}}{\text{Empirical formula weight}}[/tex]
= [tex]\frac{386.64}{56}[/tex]
= 7
Molecular formula = Empirical formula × n
= 7 (C₃H₄O₁)
Thus from the above conclusion we can say that The main constituent of gallstones is cholesterol. Cholesterol may have a role in heart attacks and blood clot formation. Its elemental percentage composition is 83.87% C, 11.99% H, and 4.14% O. It has a molecular weight of 386.64 amu. Empirical formula is C₃H₄O₁ and Molecular formula is 7(C₃H₄O₁).
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How does the tundra contribute to a reduction of carbon dioxide on earth? how is climate change affecting the tundra’s ability to reduce carbon dioxide? (site 1)
This causes organic matter to decompose faster, releasing larger amounts of carbon dioxide into the atmosphere
As a result of climate change, tundra soils are thawing deeper and deeper and for a longer time in the upper layers of surface.
What is Tundra ?The tundra is a biome on the Earth that covers approximately 20% of its land mass, and it is almost exclusively located in the Northern Hemisphere.
It is an environment that helps in the regulation of the CO2 in the atmosphere, and it is one of the biggest natural CO2 sinks. The living organisms in the tundra, are using the CO2 for their needs, thus removing parts of it from the atmospherewhen they are no more, because the tundra is cold, and the decomposition is very slow, most of the CO2 remains trapped, and doesn't go into the atmosphere.Learn more about Tundra here:
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John has been feeling ill all day. He arrives home from work and takes his temperature. Unfortunately, the thermometer shows his temperature in Celsius, and he can’t get it to change. It reads 40 degrees Celsius. What is his temperature in Fahrenheit?
Answer:
[tex]40 \times 1.8 + 32 = 104[/tex]Explanation:
The best way to change Celsius to Fahrenheit is to times it by 1.8 then plus 32
If the ph of a solution is 6.1 what is the concentration of h+ ions in the solution
Answer:
[tex]10^{-6} \frac{mol}{L}[/tex]
Explanation:
Comparing to the solution consisting a pH of 5 containing [tex]10^{-5}[/tex] [tex]\frac{mol}{L}[/tex] of hydrogen ions, a solution having a pH of 6 consists of [tex]10^{-6} \frac{mol}{L}[/tex] of hydrogen ions. A solution having a pH of 7 too will have a pH of [tex]10^{-7} \frac{mol}{L}[/tex].
By now you should realize that having an octet of electrons on a central atom is critical for a molecule to be stable. Would you expect NO and NO2 to be stable molecules
NO is a stable compound
The octet rule describes an atom's propensity to favor eight electrons in its valence shell. Atoms with fewer than eight electrons are more likely to interact with one another and create a more stable compound.
The majority of other odd-electron molecules, including NO, are highly chemically reactive and stable compounds. The second breach of the octet rule is the presence of molecules lacking electrons. Less than eight electrons are positioned around each atom in these stable compounds.
The overall molecular orbital arrangement of NO will be as follows, nitrogen has 7 electrons and oxygen has 8 electrons, according to the molecular orbital theory.
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Which statements describe some of the original ideas proposed about the universe during the big bang? Check all that apply.
The statements which describe some of the original ideas proposed about the universe during the big bang include:
The universe was opaque. The universe was very dense and hot. The universe expanded from a single point. What is Big bang theory?This theory describes how the universe expanded from a single point to form the earth we are living in.
it states that the very dense and hot environment led to it thereby making it the most appropriate choice.
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Give the coordination number and the charge of the central metal ion in each coordination compound: For the charges, enter your answers with the correct sign. e.g. if you think the answer is 1, enter the positive sign followed by the number 1. Na2[Zn(OH)4] coordination number
The coordination number shows the number of ligands attached to the central metal.
What is complex in coordination compound?A coordination complex is the product of a Lewis acid-base reaction in which neutral molecules or anions (called ligands) bond to a central metal atom (or ion) by coordinate covalent bonds. Ligands are Lewis bases - they contain at least one pair of electrons to donate to a metal atom/ion.A complex is a coordination compound which contains a central metal atom or ion. The coordination number refers to the number of ligands in the complex. The coordination number usually influences the geometry of the complex compound.The coordination number and the charge on the central metal in each of the complexes are shown below;
Na2[Zn(OH)4] - The coordination number of the complex is 4 and the charge on the central metal ion is +2.
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Positron emission tomography (pet) imaging relies upon the emission of __________ from radioactive isotopes such as carbon-11.
Answer:
positron
Explanation:
PET scanning works by injecting a radioactive material, called a tracer, into the body. The tracer emits a positron inside the body, and the positron collides with electrons in the body, thereby annihilating and releasing two gamma rays that travel in opposite directions.
The correctly reported volume for a rectangular solid that is found to be
12.49 cm x 4.00 cm x 0.90 cm is
cm³?
The chemotherapy drug cis-platin, Pt(NH3)2Cl2, is prepared via the chemical reaction shown below.
(NH4)2PtCl4 + NH3 ---> Pt(NH3)2Cl2 + NH4Cl
What volume of 0.400 M NH3 (ammonia) is required to completely react with 25.00 mL of a 0.100 M solution of the platinum-containing starting compound, (NH4)2PtCl4?
Answer:
12.5 mL NH₃
Explanation:
To find the volume of NH₃, you need to (1) find the moles (NH₄)₂PtCl₄ (using the molarity equation), then (2) convert moles (NH₄)₂PtCl₄ to moles NH₃ (via mole-to-mole ratio from balanced equation, and then (3) find the volume NH₃ (using the molarity equation).
(Step 1)
25.00 mL / 1,000 = 0.025 L
Molarity = moles / volume (L)
0.100 M = moles / 0.025 L
0.0025 = moles (NH₄)₂PtCl₄
(Step 2)
The unbalanced equation:
(NH₄)₂PtCl₄ + NH₃ ----> Pt(NH₃)₂Cl₂ + NH₄Cl
Reactants: 2 nitrogen, 11 hydrogen, 1 platinum, 4 chlorine
Products: 2 nitrogen, 10 hydrogen, 1 platinum, 3 chlorine
The balanced equation:
(NH₄)₂PtCl₄ + 2 NH₃ ----> Pt(NH₃)₂Cl₂ + 2 NH₄Cl
Reactants: 3 nitrogen, 14 hydrogen, 1 platinum, 4 chlorine
Products: 2 nitrogen, 14 hydrogen, 1 platinum, 4 chlorine
0.0025 moles (NH₄)₂PtCl₄ 2 moles NH₃
---------------------------------------- x ------------------------------ = 0.0050 moles NH₃
1 mole (NH₄)₂PtCl₄
(Step 3)
Molarity = moles / volume (L)
0.400 M = 0.0050 moles / volume
(0.400 M) x volume = 0.0050 moles
volume = 0.0125 L NH₃
0.0125 L x 1,000 = 12.5 mL NH₃
The labels required by the Department of Transportation (DOT) must be placed on ________ when chemicals are being shipped. These labels may look similar to GHS pictograms and categorize hazardous chemicals into ________ different categories. The labels required by the Department of Transportation (DOT) must be placed on ________ when chemicals are being shipped. These labels may look similar to GHS pictograms and categorize hazardous chemicals into ________ different categories.
The labels required by the Department of Transportation (DOT) must be placed on outside containers when chemicals are being shipped.
These labels may look similar to GHS pictograms and categorize hazardous chemicals into nine different categories.
OSHA recently revised the Hazard Communication Standard, and as part of that modification, new standards for labeling dangerous chemicals were established.
As a result, workers will have better information available on the safe handling and use of hazardous chemicals, thereby allowing them to avoid injuries and illnesses related to exposures to hazardous chemicals.
These modifications will aid in ensuring higher standards and uniformity in the categorization and labeling of all substances.
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Which image best represents a solution of distilled water at pH = 7?
Answer:
nuetral
Explanation:
water has neutral
In a voltaic cell, a salt bridge is needed to allow the motion of ____________ between the terminals. In the salt bridge, _____________ move toward the anode and _________ move toward the cathode.
In a voltaic cell, a salt bridge is needed to allow the motion of ions between the terminals. In the salt bridge, anions move toward the anode and cations move toward the cathode.
What is a voltaic cell?A voltaic cell is an electrochemical device that harnesses the power of a chemical process to generate electrical energy. A voltaic cell's key components are:
Anode, an electrode where oxidation takes place. Anions move toward the anode.Cathode, an electrode where reduction takes place. Cations move toward the cathode.A salt bridge is an electrolyte chamber required to finish the circuit in a voltaic cell.Half-cells are containers that serve as a barrier between the oxidation and reduction reactions.The external circuit, which typically has a load attached to it, is used to carry electron flow between the voltaic cell's electrodes.A load is a component of a circuit that uses an electron flow to carry out a certain task.Working of a voltaic cell:When an electrode is dipped into the electrolyte at the electrode and electrolyte contact surface in a voltaic cell, the electrode's atoms tend to produce positive ions in the electrolytic solution while leaving the electrode's electrons unaffected. The electrode thus acquires a negative charge.
Additionally, the electrolytic solution's positive ions have a propensity to deposit on the electrode, giving it a positive charge. The electrodes get positively or negatively charged in relation to the electrolyte as a result of the two opposite processes. As a result, there is a potential difference between the electrode and electrolyte. The term "electrode potential" refers to this potential difference.
Now, the electrode where reduction occurs is known as the cathode and turns positive in relation to the electrolytic solution, whereas the electrode where oxidation occurs is known as the anode and has a negative potential in relation to the electrolytic solution. This caused a potential difference to form between the voltaic cell's two electrodes. Cell Potential is the name given to this potential differential.
The voltaic cell's potential is sometimes referred to as its electromotive force (EMF) when no current is being drawn from it. Electrons begin to flow from the anode (negative electrode) to the cathode when an external circuit is connected to the voltaic cell (positive electrode). As a result, in the external circuit, the normal current flows from the positive terminal to the negative terminal.
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Bonding gels and _____ are designed specifically to improve adhesion of light cured gels to the natural nail plate. glossing gels self-leveling gels gel primers building gels
Bonding gels and gel primers are designed specifically to improve adhesion of light cured gels to the natural nail plate and is therefore denoted as option C.
What is Adhesion?This is defined as the tendency of particles or substance which have dissimilar origins to stick to one another. A common adhesive is referred to as glue, cement etc and ensures there is enough resistance for their separation in case of the presence of any type of external force or stimuli acting on them.
Gel primer is referred to a vital used in makeup and serves as a form of foundation before they are applied on the skin of individuals so as to enable it stick and also look more presentable.
This is therefore the reason why gel primers was chosen as the most appropriate choice.
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The "barking dog" reaction is an exciting combustion reaction that generates a bright blue flame because sulfur is produced during the reaction (sulfur burns blue!). At the end of the reaction, a "woosh" sound is made which sounds like a dogs bark (hence the name of the reaction). Assume the reaction is carried out in a closed container. CS₂ + 4N₂0 CO₂ + SO₂ + S + 4N₂ Note: the equation is balanced How many moles of CO₂ can you generate if you were to carry out the reaction with 8.28 g CS₂?
From the mole ratio CO₂ and CS₂ in the reaction, the moles of CO₂ produced is 0.109 moles.
What is the mole ratio of the reaction?
The mole ratio of the reaction is the ratio in which the reactants combine to form products.
The mole ratio of the reaction is obtained from the equation of the reaction.
The equation of the reaction is given below:
CS₂ + 4N₂0 → CO₂ + SO₂ + S + 4N₂Mole ratio of CO₂ and CS₂ is 1 : 1
Moles of CS₂ reacting = mass/molar mass
Molar mass of CS₂ is 76 g/mol
Mass of CS₂ reacting is 8.28 g
Moles of CS₂ reacting = 8.28/76
Moles of CS₂ reacting = 0.109 moles
Based on the mole ratio of the reaction, moles of CO₂ produced is 0.109 moles.
In conclusion, the moles of CO₂ produced is determined from the mole ratio CO₂ and CS₂ in the reaction.
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Why is the practice of using a spatula to scoop powder from a bottle discouraged?
Answer:
it's both impossible and inefficient
Explanation:
think about it, if your spatula can even fit in the bottle will it take out a measured amount of powder? if the spatula has holes in it the powder will fall out and you will have to restart the experiment
Determine the limiting reagent in the following equation for the production of salt and determine the amount of NaCl produced and the mass of excess reagent. (I - 10 marks)
100g 100g
NaHCO3 + HCl —> NaCl + H2O + CO2
Answer:
Limiting Reagent: NaHCO₃
Amount of NaCl: 69.6 g NaCl
Mass of Excess Reagent: 56.6 g HCl
Explanation:
To find the mass of NaCl, you need to (1) convert mass reactant to moles reactant (via molar mass), then (2) convert moles reactant to moles NaCl (via mole-to-mole ratio from equation coefficients), and then (3) convert moles NaCl to mass NaCl (via molar mass).
Molar Mass (NaHCO₃):
22.990 g/mol + 1.008 g/mol + 12.011 g/mol + 3(15.998 g/mol)
Molar Mass (NaHCO₃): 84.003 g/mol
Molar Mass (HCl): 1.008 g/mol + 35.453 g/mol
Molar Mass (HCl): 36.461 g/mol
Molar Mass (NaCl): 22.990 g/mol + 35.453 g/mol
Molar Mass (NaCl): 58.443 g/mol
100 g NaHCO₃ 1 mole 1 mole NaCl 58.443 g
------------------------ x ------------------ x --------------------------- x ---------------- =
84.003 g 1 mole NaHCO₃ 1 mole
= 69.6 g NaCl
100 g HCl 1 mole 1 mole NaCl 58.443 g
---------------- x ------------------ x ----------------------- x ---------------- =
36.461 g 1 mole HCl 1 mole
= 160 g NaCl
Since NaHCO₃ results in the smaller amount of product, it is the limiting reagent. In other words, it is used up before the HCl has the chance to completely react. Therefore, the actual amount of NaCl produced is 69.6 grams.
To find the mass of the excess reagent, you need to calculate the amount of HCl actually used in the reaction. Then, you need to subtract that value from the total amount of HCl.
69.6 g NaCl 1 mole 1 mole HCl 36.461 g
--------------------- x ------------------ x ----------------------- x ---------------- =
58.443 g 1 mole NaCl 1 mole
= 43.4 g HCl
Amount Given - Amount Reacted = Mass Excess
100 g HCl - 43.4 g HCl = 56.6 g HCl
The equilibrium constant for the reaction shown here is Kc=5.0×102. A reaction mixture at equilibrium contains [A]=1.0×10−3M. What is the concentration for the B mixture?
A(g)⇌B(g)
Here are the choices:
A. 1.0×10−3M
B. 5.0×102M
C. 1.0 M
D. 0.50 M
D. The concentration for the B mixture is 0.5 M.
concentration for the B mixturekc = [B]/[A]
where;
kc is equilibrium constantA is the concentration for the A mixtureB is the concentration for the B mixtureB = kc(A)
B = (5x 10²)(1 x 10⁻³)
B = 0.5 M
Thus, the concentration for the B mixture is 0.5 M.
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Need quickly!
what is the name of pb(no3)2? explain how you determined the bond type and the steps you used to determine the naming convention for the compound.
The name of pb(no3)2 is Lead(II) nitrate.
Type of bond:pb(no3)2 is an ionic compound.
How to name ionic compound?
The name of an ionic compound is written as its cation followed by anionThe charge of cation should be written in Roman lettersThe net charge of ionic compounds is generally zeroName of pb(no3)2:
The charge of nitrate ion NO3 is -1. To find the charge of lead, we'll take it as x. Hence,
x+2(-1)=0
x=2
The charge of lead cation in this ionic compound is calculated as +2.
Therefore the name of pb(no3)2 is confirmed as Lead(II) Nitrate.
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Place the following substances in order of increasing vapor pressure at a given temperature. SF6 SiH4 SF4
Substances in order of increasing vapor pressure at a given temperature is SF4 < SF6 < SiH4
The substance with the lowest vapor pressure will also have the greatest boiling point. A liquid attribute associated with evaporation is vapor pressure. The distribution of kinetic energy among the molecules in a liquid (or any substance) is influenced by the system's temperature.How do you determine vapor pressure?Vapor pressure in chemistry is the force that an evaporating substance exerts against the walls of a sealed container (converts to a gas). Use the Clausius-Clapeyron equation to determine the vapor pressure at a specific temperature: ln(P1/P2) = (Hvap/R)((1/T2) - (1/T1)Which has highest vapor pressure?
At the normal boiling point of a liquid, the vapor pressure is equal to the standard atmospheric pressure defined as 1 atmosphere, 760 Torr, 101.325 kPa, or 14.69595 psi. For example, at any given temperature, methyl chloride has the highest vapor pressure of any of the liquids in the chart.Learn more about vapor pressure
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In a titration of a monoprotic weak acid with sodium hydroxide, the ph at the half-equivalence point is 4. 20. What is the experimental ka value of this acid?.
Ka value of monoprotic weak acid:
The experimental ka value of this acid is 6.3 × [tex]10^{-5}[/tex]
Half-equivalence point:
The pH of the solution will be equal to the pKa of the weak acid at the half-equivalence point.At the equivalence point, the strong base OH- will neutralize the weak acid in the case of a weak monoprotic acid, which I'll denote as HA.HA + OH⁻ → A⁻ + H₂OThe moles of OH are equivalent to the moles of the acid since the acid is monoprotic:
At half equivalence point, pH = pKₐ
The pKa is determined by the weak acid's Ka acid dissociation constant.
pKₐ = -log(Kₐ)
Kₐ = [tex]10^{-pKa}[/tex]
At the half equivalence point,
Kₐ = [tex]10^{-pH}[/tex]
Given,
pH = 4.20. By putting the value;
Kₐ = [tex]10^{-4.20}[/tex]
= 6.3 × [tex]10^{-5}[/tex]
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The element with the lowest melting point is: Select one: a. B b. Al c. Ga d. Tl e. All of these have the same melting point.
The element with the lowest melting point is Ga.
Hence, Option (C) is correct answer.
Melting point is usually defined as the temperature at which solid changes to liquid.
What is the order of melting point of B, Al, Ga, Tl ?The melting point order of B, Al, Ga, Tl is B > Al> Tl > Ga due to structural changes, melting point increases from Ga to Tl. Hence Ga has the lowest melting point among all these.
Thus from the above conclusion we can say that The element with the lowest melting point is Ga.
Hence, Option (C) is correct answer.
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PLEASE HURRY AND HELP
Write the empirical formula for at least four ionic compounds that could be formed from the following ions:
Fe²+, CH₂CO₂, Pb4+, MnO-4
Answer:
Fe(CH₂CO₂)₂, Fe₂MnO, Pb(CH₂CO₂)₄, PbMnO
Explanation:
Cations (positively charged ions) can only form ionic bonds with anions (negatively charged ions). However, you can't just simply put one cation and one anion together to form a compound. Each compound needs to been neutral, or have an overall charge of 0. When cations and anions do not have charges that perfectly cancel, you need to modify the amount of each ion in the compound.
1.) Fe(CH₂CO₂)₂
----> Fe²⁺ and 2 CH₂CO₂⁻
----> +2 + (-1) + (-1) = 0
2.) Fe₂MnO
----> 2 Fe²⁺ and 1 MnO⁴⁻
----> 2(+2) + (-4) = 0
3.) Pb(CH₂CO₂)₄
----> 1 Pb⁴⁺ and 4 CH₂CO₂⁻
----> +4 + (-1) + (-1) + (-1) + (-1) = 0
4.) PbMnO
----> 1 Pb⁴⁺ and 1 MnO⁴⁻
----> +4 + (-4) = 0
If the same test, given at different points in time to the same test takers, yields different scores, then the method typically used to assess this source of error is_________.
If the same test, given at different points in time to the same test takers, yields different scores, then the method typically used to assess this source of error is alternate form.
What is alternate forms test?
An alternate form or parallel form test is a test which is conducted at different time on the same set of test takers in order to test the reliability of the results obtained.
In conclusion, alternate or parallel form tests is a test of reliability.
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How many sulfur dioxide molecules are in 2.8 moles of sulfur dioxide?
Answer:
1,69 x10²⁴
Explanation:
Answered it in the comments! ^^