Kylee

The decomposition of N2O5 to NO2 and O2 is first order with a rate constant of 4.80 × 10−4/s at 45°C. If the initial concentration of N2O5 is 0.0165 M, what is the concentration after 825 seconds?

Select one:

a. 0.0111 M

b. 0.0411 M

c. 0.00663 M

d. 0.00653 M

e. 0.0245 M

A possible mechanism for the decomposition of hydrogen peroxide is shown below:

H2O2 + Br– → BrO– + H2O

H2O2 + BrO– → Br– + H2O + O2

The catalyst in this reaction is:

Select one:

a. O2

b. Br−

c. H2O2

d. BrO−

e. H2O

Gaseous chlorine is allowed to react with 0.5 grams of aluminum at 25°C. Which of the following choices would give the fastest rate?

Select one:

a. All choices would react at the same rate since the temperature is the same.

b. 0.5 grams of aluminum in 10 spheres

c. 0.5 grams of aluminum in 1000 spheres

d. 0.5 grams of aluminum in one sphere

e. 0.5 grams of aluminum in 100 spheres

For which reaction order (zero, first, second) does the half-life NOT depend on the initial concentration of the reactant?

Select one:

a. second order only

b. zero and second order only

c. zero and first order only

d. zero order only

e. first order only

Data is plotted for the zero order reaction A → products. Which one of the following plots should give a straight line?

Select one:

a. ln[A] vs. t

b. 1/[A]2 vs. t

c. [A] vs. t

d. [A]2 vs. t

e. 1/[A] vs. t

The solubility of CO2 gas in water:

Select one:

a. increases with decreasing temperature

b. is not dependent on either temperature or pressure

c. increases with increasing temperature

d. increases with decreasing pressure

e. decreases with increasing pressure

When 0.500 grams of a certain protein is dissolved in 75.0 mL of water at 20°C, the osmotic pressure is 1.24 torr. What is the molar mass of the protein?

Select one:

a. 200 g/mole

b. 1.60 × 105

c. 1.09 × 104

d. 210 g/mole

e. 1.62 × 107

Glycerin (molar mass = 92.09 g/mole) is a nonvolatile nonelectrolyte that has a density of 1.26 g/mL at 25°C. The vapor pressure of water at 25°C is 23.8 torr. Calculate the vapor pressure at 25°C of a solution made by adding 50.00 mL of glycerin to 500.0 grams of water (molar mass = 18.015 g/mole).

Select one:

a. 0.573 torr

b. 24.4 torr

c. 23.8 torr

d. 0.587 torr

e. 23.2 torr

The concentration of electrolytes inside red blood cells is about 0.015 M. If red blood cells are placed in an aqueous 2.0 M solution of NaCl, which of the following will be true?

Select one:

a. The 2.0 M solution is a hypotonic solution.

b. The 2.0 M solution is a hypertonic solution.

c. Some NaCl will enter the red blood cells.

d. The red blood cells will swell and burst.

e. The 2.0 M solution is an isotonic solution.

The specific heat of liquid water is 4.184 J/g°C, and the specific heat of steam is 1.99 J/g°C. The heat of vaporization of water at its boiling point is 2264 J/g. Assume the boiling point of water is 100.0°C. When 150.0 kJ of heat are added to 50.0 grams of water at 20°C, the final temperature of the resulting steam will be closest to

Select one:

a. 100°C

b. 637°C

c. 401°C

d. 202°C

e. 302°C