The given question is incomplete. The complete question is:
The standard heat of combustion is shown in the following chemical equation [tex]C_9H_{20}(g)+14O_2(g)\rightarrow 9CO_2(g)+10H_2O[/tex][tex]\Delta H_{rxn}=-6125.21kJ/mol[/tex]. If 130 g of nonane combusts , how much heat is released?
Answer: 6211.21 kJ
Explanation:
Heat of combustion is the amount of heat released on complete combustion of 1 mole of substance.
Given :
Amount of heat released on combustion of 1 mole of nonane = 6125.21 kJ
According to avogadro's law, 1 mole of every substance occupies 22.4 L at NTP, weighs equal to the molecular mass and contains avogadro's number [tex]6.023\times 10^{23}[/tex] of particles.
1 mole of nonane [tex](C_9H_{20})[/tex] weighs = 128.2 g
Thus we can say:
128.2 g of nonane on combustion releases = 6125.21 kJ
Thus 130 g of [tex]C_4H_{10}[/tex] on combustion releases =[tex]\frac{6125.21}{128.2}\times 130=6211.21kJ[/tex]
Thus the heat of combustion of 130 g of nonane is 6211.21 kJ
An unknown solid is added to water in a calorimeter. The temperature of the water increases. What does this say about the reaction? A) The reaction is exothermic. B) The reaction is endothermic. C) The reaction has absorbed heat from the solution. D) The reaction has released heat to the solution. E) Both A and D are correct.
Answer:
Option A is correct.
Option D is correct.
E is the correct answer
Explanation:
This a theoretical calorimetry problem that can be solved by thermodynamic concepts.
Our system is the unknown solid. If the temperature of water has increased, we can think, that the heat from the metal was absorbed by water, which is our surrounding. If in the analysis of the situation we use a calorimeter, knowing that it is an isolated system, which does not allow the entry or exit of heat, we can conclude that the heat released is equal to the heat absorbed.
In conclusion, the thermodynamic system is constituted by the chemical reaction. In this case, the surrounding is made up of water and the calorimeter itself.
If the reaction is exothermic, the heat released by the reaction will be absorbed by the surrounding . Then, the final temperature will be higher than the initial temperature. If the reaction is endothermic, the heat absorbed by the reaction will be released by the environment. So, the final temperature will be lower than the initial temperature.QUESTION 5
Which of the following is NOT electromagnetic wave?
O A. Sound wave.
O B. Microwave.
O C. Infrared wave.
O D. X-Ray.
Answer:
Beta Rays
Beta Rays are not Electromagnetic Waves
Beta rays also known as beta radiation is obtained through the emission of an electron. Beta rays are not electromagnetic waves because they are charged particles and are capable of getting deflected by the magnetic field.
5. If you advance the movie one frame, the knot at point A would be
a) in the same place b) higher
c) lower d) to the right
e) to the left
relative to the hand
6. If you advance the movie one frame, the pattern of the waves will be
a) in the same place
b) shifted right
c) shifted left
shifted up
e)
shifted down
7.
If the person starts over and moves his hand more quickly, the peaks of the waves will be
a) the same distance apart
b) further apart
c) closer together
8. If you lower the frequency of a wave on a string you will
a) lower its speed. b) increase its wavelength. c). lower its amplitude. d) shorten its period
Answer:
5. higher
6. shifted down
7. closer together
8. increase its wave length
Explanation:
what is a row of elements across the periodic table called
Answer:
a period
Explanation:
Answer: The row of elements across the periodic table is called "periods".
Explanation:
In the Periodic Table, there are seven rows of elements, which is called periods.
What will a child given a vaccine hopefully develop?
O A. Antibiotic Resistance
OB. Immunity
0
C. Mutages
D. Increased Growth
Answer:
B (immunity) is the answer
Consider the following reaction where K. = 9.52 10 2 at 350 K.
CH,(g) + CC14(2)—2CH2Cl2(g)
A reaction mixture was found to contain 2.21*10-2 moles of CH4(E), 3.8710-2 moles of CC1,(g) and 1.06-10-2 moles of CH,C12(2), in
a 1.00 liter container
Is the reaction at equilibrium?
If not, what direction must it run in order to reach equilibrium?
The reaction quotient, Qc equals
The reaction
A. must run in the forward direction to reach equilibrium
B. must run in the reverse direction to reach equilibrium
C. is at equilibrium
Answer:
The correct answer is A :))
Hydrocarbons are compounds that are composed of only carbon and hydrogen atoms. A hydrocarbon has a density of 2.59 g/L at STP. What is the molar mass of this hydrocarbon? Be sure to include units with your answer.
Answer:
58.0 g/mol
Explanation:
At STP, one mole occupies 22.4 liters. One mole of the hydrocarbon would have a mass of ...
(2.59 g/L)(22.4 L/mol) ≈ 58.0 g/mol
Answer:
58.0 g/molthe molar mass of this given hydrocarbonBased on your answers to Question 3 above, why do you think that, as a general practice, when antibiotics
(including azithromycin) are prescribed to adults, the same dose is usually given, regardless of weight of the
patient?
Answer:
See explanation below
Explanation:
Since question 3 is not here, I will answer based on a general perspective.
The dosage of most antibiotics and drugs generally are prescribed without considering the weight of adults. Unlike children that are given dosages based on their weight.
The weight of adults is not considered because the extent to which they weigh is majorly as a result of their adipose (fat) tissue. And the adipose tissue does not determine the tolerance level of drugs. So an adult weighing 200kg and another weighing 50kg will be able to tolerate the same dosage of medications.
Because the adults are adults with fully developed organs, their weight does not matter when prescriptions are made.
Witch regard to the ph scale, a solution with a ph . A. Lower than 7 is considered basic
Answer:
false
Explanation:
if it is lower than 7 It is acid
This group of fungi forms spores in a round structure on the end of a hyphae
Answer:
Is zygote fungi an option??
Answer:
zygote fungi
Explanation:
i got the answer right
What is the edge length of a 377-g iron cube? (The density of iron is 7.86 g/cm^3, and the volume of a cube is equal to the edge length cubed.)
Answer:3.50 cm
Explanation:
Answer:
3.63cm
Explanation:
The rate constant for a certain reaction is measured at two different temperatures:
temperature k
376.0 °C 4.8 x 10^8
280.0 °C 2.3 x 10^8
Assuming the rate constant obeys the Arrhenius equation, calculate the activation energy Ea for this reaction.
Answer: The activation energy Ea for this reaction is 22689.8 J/mol
Explanation:
According to Arrhenius equation with change in temperature, the formula is as follows.
[tex]ln \frac{k_{2}}{k_{1}} = \frac{-E_{a}}{R}[\frac{1}{T_{2}} - \frac{1}{T_{1}}][/tex]
[tex]k_1[/tex] = rate constant at temperature [tex]T_1[/tex] = [tex]2.3\times 10^8[/tex]
[tex]k_2[/tex] = rate constant at temperature [tex]T_2[/tex] = [tex]4.8\times 10^8[/tex]
[tex]E_a[/tex]= activation energy = ?
R= gas constant = 8.314 J/kmol
[tex]T_1[/tex] = temperature = [tex]280.0^0C=(273+280)=553K[/tex]
[tex]T_2[/tex] = temperature = [tex]376.0^0C=(273+376)=649K[/tex]
Putting in the values ::
[tex]ln \frac{4.8\times 10^8}{2.3\times 10^8} = \frac{-E_{a}}{8.314}[\frac{1}{649} - \frac{1}{553}][/tex]
[tex]E_a=22689.8J/mol[/tex]
The activation energy Ea for this reaction is 22689.8 J/mol
Consider the following elementary reaction:
2NO(g) → N2O2(g)
Suppose we let k1 stand for the rate constant for this reaction, and k-1 stand for the rate constant of the reverse reaction. Write the expression that gives the equilibrium concentration of NO in terms of k1, k-1. And the equilibrium concentration of N2O2.
Answer:
[tex][NO]=\frac{k_{-1}}{k_1} [N_2O_2][/tex]
Explanation:
Hello!
In this case, since the reaction may be assumed in chemical equilibrium, we can write up the rate law as shown below:
[tex]r=-k_1[NO]+k_{-1}[N_2O_2][/tex]
However, since the rate of reaction at equilibrium is zero, due to the fact that the concentrations remains the same, we can write:
[tex]0=-k_1[NO]+k_{-1}[N_2O_2][/tex]
Which can be also written as:
[tex]k_1[NO]=k_{-1}[N_2O_2][/tex]
Then, we solve for the concentration of NO to obtain:
[tex][NO]=\frac{k_{-1}}{k_1} [N_2O_2][/tex]
Best regards!
Write the chemical formula for this molecule O=N-CI
Explanation:
Structural Formulas v. Empirical Formulas
An empirical formula (like a molecular formula) lacks any structural information about the positioning or bonding of atoms in a molecule. It can therefore describe a number of different structures, or isomers, with varying physical properties. For butane and isobutane, the empirical formula for both molecules is C2H5, and they share the same molecular formula, C4H10. However, one structural representation for butane is CH3CH2CH2CH3, while isobutane can be described using the structural formula (CH3)3CH.
write the rate expression for the following reaction. H2+1/2
O2 arrow H2O
Answer:
[tex]r=-k[H_2][O_2]^{1/2}[/tex]
Explanation:
Hello!
In this case, according to the chemical reaction:
H2 + 1/2 O2 --> H2O
Since both hydrogen and oxygen are the reactants and the rate laws are written in terms of the concentration of reactants and the rate constant, we obtain:
[tex]r=-k[H_2][O_2]^{1/2}[/tex]
Whereas the negative sign represents the consumption of those reactants and the power 1/2 the stoichiometric coefficient of oxygen in the reaction.
Best regards!
Which of the following would make a solution?
A. Oil in water
B. Sugar in water
C. Ice in water
D. Sand in water
SUBM
The combination from the available option that will make a solution would be sugar and water.
What are solutions?Solutions are obtained when solutes dissolve in solvents.
In other words, a solute must be able to dissolve in a solvent before a solution can be formed.
Oil and water cannot mix, and thus, cannot form a solution. Sand is insoluble in water and ice and water are the same.
Thus, the only option left is sugar and water. Sugar dissolves in water to form a sugar solution.
More on solutions can be found here: https://brainly.com/question/7932885
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If a machine has an AMA of 1 what does this tell you about the RF and EF?
Answer:
Although you might think of a machine as complex system of gears, drive belts and and a motor, the definition physicists use is much simpler. A machine is simply a device that does work, and there are only six different types of simple machines. They include the lever, the pulley, the wheel and axle, the screw, the wedge and the inclined plane.
Explanation:
Which of the following are correct for zero-order reactions?
A. A higher concentration of reactants will not increase the reaction rate.
B. The units for the rate constant and the rate of reaction are the same.
C. The rate of reaction does not equal the rate constant.
D. The concentration of the reactants changes nonlinearly.
E. A zero-order reaction slows down as the reaction proceeds.
Answer:
The answer is "Choice A and Choice B"
Explanation:
The Zero-Order reactions are usually found if a substrate, like a surface or even a catalyst, is penetrated also by reactants. Its success rate doesn't depend mostly on the amounts of the various reaction in this reaction.
Let the Rate = k
As [tex]\frac{dx}{dt} \ rate\ \ K_0[/tex] doesn't depend on reaction rate, a higher reaction rate does not intensify the reaction.
By the rate [tex]k_0 =\frac{dx}{dt},[/tex] the created based and the reaction rate is about the same.
Below statement are correct about zero order reaction.
higher concentration of reactants will not increase the reaction rate. The units for the rate constant and the rate of reaction are the same. What is Zero order reaction?Zero-order reaction is a chemical reaction in which the rate of chemical reaction does not change with increase or decrease in the concentration of the reactants.
Example is the decomposition of ammonia to nitrogen and hydrogen. the rate does not vary, it is the same.
Therefore, Below statement are correct about zero order reaction.
higher concentration of reactants will not increase the reaction rate. The units for the rate constant and the rate of reaction are the same.Learn more about zero order reaction from the link below.
https://brainly.com/question/13314785
is magnesium oxide an ionic or covalent compound. what are the reasons?
Answer:
ionic
Explanation:
the bonds that hold magnesium and oxygen together are formed between atoms that give electrons
Number of liters in 0.50 moles of O2
Answer:
there are about 11.2 liters
Imagine a made-up pol
b. Write both the formula and the name for the compound formed when Cu2+
combines
with boritate? (2 pts)
Answer:
No change to the cation Add -ide to the anion
Question 1 and .2
Explanation:
What is the mole ratio between H2O and O2
A student assembles ball bearings that are 0.19 inches in diameter into an FCC lattice using glue which makes for a 0.001 inch thick bond between bearings. What is the lattice constant in inches of this FCC crystal? Three significant digits and fixed point notation.
Answer:
the lattice constant is 0.270 inches
Explanation:
Given the data in the question;
For FCC lattice;
a = b = c, ∝ = β = α = 90°
from the image below;
AC = 0.19 + 0.19/2 + 0.19/2 + 2(0.001) inch
AC = 0.19 + 0.095 + 0.095 + 0.002
AC = 0.382 inches
Now using Pythagoras theorem
AC² = AB² + BC²
since a = b = c
AC² = a² + a²
(0.382)² = 2a²
2a² = 0.145924
a² = 0.145924 / 2
a² = 0.072962
a = √0.072962
a = 0.27011 ≈ 0.270 inches
Therefore, the lattice constant is 0.270 inches
Why does heating increase the speed at which a solute dissolves in water?
O A. It decreases the surface area of the solute.
B. It prevents the solute from cristallizing.
O c. It makes the water molecules move faster.
D. It raises the pressure of the water molecules.
Answer: C
Explanation:
It gives kinetic energy to the molecules and it breaks the bonds faster because they jiggle more
What does an ion have that an atom does not?
Answer:
Atoms are neutral; they contain the same number of protons as electrons. By definition, an ion is an electrically charged particle produced by either removing electrons from a neutral atom to give a positive ion or adding electrons to a neutral atom to give a negative ion.
Explanation:
:)
Which of the following chemical reactions is a single displacement reaction?
A. 2Na + O2→
Na2O
B. 2A1 + 3Zn(NO3)2 2AI(NO3)3 + 3Zn
C. Pb(NO3)2 + 2KBr → PbBr2 + 2KNO3
D. 2Fe(OH)3 Fe2O3 + 3H2O
Answer:
B. 2A1 + 3Zn(NO3)2 --> 2AI(NO3)3 + 3Zn
Explanation:
In the chemical equation, you can see that 2Al replaced 3Zn with (NO3)3 in the product, thus it is a single displacement reaction.
Answer:
B. 2A1 + 3Zn(NO3)2 --> 2AI(NO3)3 + 3Zn
Explanation:
How many moles of KMnO4 are in 75g of KMNO4?
Answer:
0.64 mol
Explanation:
moles=mass/molar mass
n= 75/(39+14+4×16)
n=75/117
n = 0.64mol
The mass fractions of a mixture of gases are 15 percent nitrogen, 5 percent helium, 60 percent methane, and 20 percent ethane with a total mixture molecular weight of 16.12 kg/kmole. Determine the mole fraction of each constituent, the partial pressure of each constituent when the mixture pressure is 1200 kPa and the apparent specific heats of the mixture when the mixture is at room temperature.
Answer:
Explanation:
mass fraction N₂ : He : CH₄ : C₂H₆ : : 15 : 5 : 60 : 20
mole fraction N₂ : He : CH₄ : C₂H₆ : : 15/28 : 5/4 : 60/16 : 20/30
mole fraction N₂ : He : CH₄ : C₂H₆ : : .5357 : 1.25 : 3.75 : .67
Total mole fractions = .5357 + 1.25 + 3.75 + 0.67 = 6.2057
mole fraction of N₂ = .5357 / 6.2057 = .0877
mole fraction of He = 1.25 / 6.2057 = .20
mole fraction of CH₄ = 3.75 / 6.2057 = .6043
mole fraction of C₂H₆ = .67 / 6.2057 = .108
Partial pressure = total pressure x mole fraction
Partial pressure of N₂ = 1200 kPa x .0877 = 105.24 kPa
Partial pressure of He = 1200 kPa x .20 = 240 kPa
Partial pressure of CH₄ = 1200 kPa x .6043 = 725.16 kPa
Partial pressure of C₂H₆ = 1200 kPa x .108 = 129.6 kPa
Calculate: Press Reset. Start with 1.900 × 10 24(or 19.00 × 10 23 ) molecules of Cu2O. A. Calculate the number of moles: B. Use the Gizmo to verify your calculation. Were you correct? C. Is the method for converting molecules to moles the same as that for atoms?
Answer:
1.661 mol.
Explanation:
Hello!
In this case, since the Avogadro's number allows us to relate the number of formula units in one mole of the substance; we need to keep in mind that elements are related by atoms and compounds by molecules, it means:
[tex]1 mol = 6.022x10^{23}atoms\\\\1 mol = 6.022x10^{23}molecules[/tex]
Thus, for copper (I) oxide, we compute the moles, given the atoms as shown below:
[tex]n = 1.900x10^{24}molecules*\frac{1mol}{ 6.022x10^{23}molecules} \\\\n = 1.661mol[/tex]
Thus, the method we use is the same.
Best regards
The following aqueous solutions of are mixed: 100.0 mL of 1.00 M lithium bromide and 100.0 mL of 1.00 M lead (II) nitrate. In an organized and clear manner, show all of your work and answers for this problem on the uploaded work. (a) Write the molecular equation for this reaction. (b) Write the total ionic chemical equation for this reaction. (c) Write the net ionic chemical equation for this reaction. (d) Identify the spectator ions in this reaction. (e) Identify the limiting reactant. (f) Determine the mass of solid product that is formed?
Answer and Explanation:
(a) When lithium bromide (LiBr) solution is mixed with a solution of lead (II) nitrate (Pb(NO₃)₂), lithium nitrate (LiNO₃) and lead (II) bromide (PbBr₂) are formed, according to the following molecular equation:
2LiBr(aq) + Pb(NO₃)₂(aq) → 2LiNO₃(aq) + PbBr₂(s) ↓
As the product PbBr₂ is an insoluble solid, it precipitates (↓).
(b) The total ionic equation is written with all ions of the reaction - no matter if they participate in the precipitate formation or not:
2Li⁺(aq) + 2Br⁻(aq) + Pb²⁺(aq) + 2NO₃⁻(aq) → 2Li⁺(aq) + 2NO₃⁻(aq) + PbBr₂(s)
(c) The net ionic equation is written including only the ions which participate in the precipitate formation. In this case, the precipitate is PbBr₂, and it is formed by Pb²⁺ and Br⁻ ions:
Pb²⁺(aq) + 2Br⁻(aq) → PbBr₂(s)
(d) The spectator ions are those which do not participate in the formation of the precipitate. From the total ionic equation, we can see that Li⁺ and NO₃⁻ ions are repeated on both sides of the equation, so they are redundant. Thus, the spectator ions are Li⁺ and NO₃⁻ ions.
(e) To identify the limiting reactant, we first calculate the moles of each compound as the product of the solution concentration and volume:
For LiBr:
C = 1.00 M = 1 mol/L
V = 100.0 mL x 1 L/1000 mL = 0.1 L
moles of LiBr = 0.1 L x 1.00 mol/L = 0.1 mol
The same for Pb(NO₃)₂:
C = 1.00 M = 1 mol/L
V = 100.0 mL x 1 L/1000 mL = 0.1 L
moles of Pb(NO₃)₂ = 0.1 L x 1.00 mol/L = 0.1 mol
From the total ionic equation, we can see that 2 mol of LiBr reacts with 1 mol of Pb(NO₃)₂ to give 1 mol of PbBr₂ (solid product). The stoichiometric molar ratio is 2 mol LiBr/1 mol Pb(NO₃)₂ and we have 0.1 mol of each reactant (0.1 mol LiBr/0.1 mol Pb(NO₃)₂= 1). As 2 mol LiBr/mol Pb(NO₃)₂ > 1 mol LiBr/mol Pb(NO₃)₂, LiBr is the limiting reactant.
(f) From the total ionic equation, we know that 2 moles of LiBr produce 1 mol of PbBr₂. To determine the mass of solid product (PbBr₂) formed, we first multiply the stoichiometric ratio (1 mol PbBr₂/2 mol LiBr) by the actual number of moles of limiting reactant we have (0.1 mol):
moles of PbBr₂ = 0.1 mol LiBr x (1 mol PbBr₂/2 mol LiBr) = 0.05 mol PbBr₂
Finally, we convert the moles of PbBr₂ to gram by using the molar mass of the compound:
Molar mass PbBr₂ = 207.2 g/mol + (2 x 79.9 g/mol) = 367 g/mol
grams of PbBr₂ = 0.05 mol x 367 g/mol = 18.35 g