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Does The Heat Often Lack Chemistry

Chemistry help please?

Predict the changes in equilibrium position for this reaction when the following changes are made. In each case, state whether the change causes a shift that favors the formation of reactants or products:
2A(g) + B(g) ---> 4C(g) + heat
..................<---

a.) decrease the concentration of C
b.) add more heat
c.) increase the concentration of A
d.) increase the pressure

CHEMISTRY HELP! PLEASE!?

So I have a chem. lab and one of my online problems is copied below. I have absolutely no idea how to solve all but one of them and the prof. doesn't show you how to do this you have to figure it out on your own and I cannot do it! If anyone knows how to do it could you please show me step by step what to do?!
THANKS! :D

In one experiment, the mass of water is 103 grams, the initial temperature of the water is 63.9oC, the mass of liquid nitrogen added to the water is 62.2 grams, and the final temperature of the water, after the liquid nitrogen has vaporized, is 34.9oC.

Specific heat of water = 4.184 J K-1g-1

How much heat is lost by the warm water? ( this is the only one I know how to solve!)

What is the heat of vaporization of nitrogen in J g-1?

What is the molar heat of vaporization of nitrogen?

Trouton's constant is the ratio of the enthalpy (heat) of vaporization of a substance to its boiling point (in K). The constant is actually equal to the entropy change for the vaporization process and is most often a measure of the entropy in the liquid state. The value of the constant usually lies within the range 70 to 90 J K-1mol-1, with a value toward the lower end indicating high entropy in the liquid state.

The normal boiling point of liquid nitrogen is -196C. Based upon your results above, what is the value of Trouton's constant?

Trouton's constant = ?

....Anyone?

Need help with Chemistry?

3. A.
(173 g CuSO4·5H2O) / (249.6861 g CuSO4·5H2O/mol) x (1 mol CuSO4 / 1 mol CuSO4·5H2O) x (159.6095 g CuSO4/mol) = 111 g CuSO4

3.B.
(2.50 mol CuSO4) x (1 mol CuSO4·5H2O / 1 mol CuSO4) x
(249.6861 g CuSO4·5H2O/mol) = 624 g CuSO4·5H2O

9.
2 Al + Cr2O3 → 2 Cr + Al2O3

(10.0 kg Cr2O3) / (151.99061 g Cr2O3/mol) x (2 mol Al / 1 mol Cr2O3) x
(26.98154 g Al/mol) = 3.55 kg Al

(2.54 kg Al) / (26.98154 g Al/mol) x (2 mol Cr / 2 mol Al) x (51.99616 g Cr/mol) = 4.89 kg Cr

(4.89 kg Cr) / (51.99616 g Cr/mol) x (1 mol Cr2O3 / 2 mol Cr) x (151.99061 g Cr2O3/mol) = 7.15 kg Cr2O3 reacted

(10.0 kg Cr2O3 initially) - (7.15 kg Cr2O3 reacted ) = 2.85 kg Cr2O3 left over

Chemistry help PLEASE?

1. First you need the energy required to heat it from -154ºC to -95ºC

q = mct
q = (87.1g)*(1.65 J/g°C)*(59)
q = 8.479185 kJ

Then you need the heat of fusion

q = (ΔHfus)*(m)/(FM)
q = (7.27)*(87.1/58.08)
q = 10.902497 kJ

Then you need the heat required to bring it from -95 to -42

q = mct
q = (87.1)*(2.16)*(53)
q = 9.971208 kJ

Add the three together, and you get an answer near 29.4 kJ, answer (A)

2. Vapor pressure increases with an increase in molecular mass

SF6 = 146.053
SiH4 = 32.086
SF4 = 108.057

Thus, SiH4 has the least vapor pressure and SF6 has the most.

3. Vapor pressure increases with an increase in molecular mass

PF5 = 125.964
BrF3 = 136.898
CF4 = 68.994 (g/mol)

Thus, BrF3 is has the most vapor pressure and CF4 has the least.

How do I get my natural curls back after straightening and chemicals?

Eat foods enriched with vitamins c d and e also B since they provide a you with a stronger immune system and promote hair follicles to leave more dead cells behind(Hair).

Need your help with this Chemistry question!?

This is the simplest language i can put it:
During any chemical reaction bonds are broken between atoms or
ions in the reactants, and new bonds are made between atoms or
ions to form the products. It requires energy to break bonds, and
energy is released when new bonds are formed. If more energy
is given out than needs to be put in then this will be released as
heat, and the reaction is said to be exothermic. If more energy is
required to break the reactant bonds than is given out when the
products are formed then extra heat will need to be added, and
the reaction is said to be endothermic. The bonds that are present
between atoms within a molecule are due to intramolecular forces
of attraction. These forces of attraction tend to be strong.
When a substance changes state from a solid to a liquid or from a
liquid to a gas, then bonds are also broken. However, in this case
no new chemical substance is formed, so the change is a physical
change. The bonds that are broken in physical changes are the
forces of attraction between the particles of the compound that
hold it together in the solid or liquid state. These are known as
intermolecular forces of attraction. For this reason a few ice cubes
are much more effective than the same mass of cold water at cooling
a drink, because heat is absorbed in breaking down the structure
of the ice. When the change of state is in the other direction, and
intermolecular forces of attraction are being formed, heat is given
out. Thus when steam condenses to liquid water at 100 °C heat
is evolved, even though the temperature remains constant. This
explains why steam at 100 °C will cause a worse scald than water
at 100 °C.
In this chapter we shall first look at the different ways in which
atoms or ions can bond together in compounds. Then we shall
consider how the properties of the molecules or ions formed
determine the type of intermolecular forces of attraction between
them, and hence their melting and boiling points and other physical
properties.

Chemistry question. Balancing equations.I will provide you with a best answer.?

Liquefied propane gas is often used for cooking in suburban areas away from natural gas lines. Propane (C3H8) burns in oxygen gas, producing carbon dioxide gas, water vapor, and heat. Write the unbalanced chemical equation for this process. (Include states-of-matter under the given conditions in your answer.)

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