Question

1. There are 3.01 x 10^23 atoms present in

a) 0.5 mol of Na

b) 0.5 mol of C

c) 0.5 mol of Ar

d) none of the above

e) all of the above

2. Which of the following scenarios does NOT represent a quantitative analysis?

a) A chemist tests a sample of water for the presence of chloride ions.

b) A police officer uses a breathalyzer to measure the amount of alcohol in exhaled air.

c) A lifeguard tests a sample of water to see how much disinfectant is present in the water.

d) A sample of soil from a farm is tested for dangerously high levels of bacterial content.

e) all of the above

3. Which of the following is not a property of solutions?

a) solutions are homogeneous

b) solutions contain more than one visible part

c) solutions are mixtures

d) solutions can be separated by physical means

4. How could a saturated solution of KNO3 be made unsaturated?

a) by raising the ternperature

b) by raising the pressure

c) by evaporating some of the water

d) by adding a crystal of potassium nitrate

e) by increasing the concentration

5. How would you describe a solution of KNO3 at 80 degrees Celsius and with 45 grams of solute in 100 grams of water solvent?

a) supersaturated

b) dilute

c) saturated

d) unsaturated

6. Which substance contains the greatest amount of moles of carbon atorns per rnole of compound?

a) C7H5NO3S

b) C8H10N4O2

c) C9H8O4

d) CCl4

10. Determine the number of moles of water produced if 4.0 mol of O2 are completely reacted according to the following balanced equation:

2 C3H6 + 9 O2 = 6 CO2 + 6 H2O

A) 1.5 mol

B) 4.8 mol

c) 1.9 mol

d) 6.0 mol

e) 2.7 mol

8) What is the percentage, by mass, of oxygen in carbon dioxide?

a. 27.396

b. 36.496

c. 57.196

d. 72.796

Answer 1