SCIENCE/CHEMISTRY
Directions: Choose the letter of the correct answer. Write your answers on a separate

sheet of paper.

1. How many particles are equal to 1 mole?

a. 6.02 x 1022 particles

c. 6.02 x 1024 particles

b. 6.02 x 1023 particles

d. 6.02 x 1025 particles

2. The presence of SO2 in the atmosphere causes acid rain. How many percent of

sulfur is present in SO2 (Molar Mass = 64.07g/mole)?

a. 40.00%

c. 49.95%

b. 60.00%

d. 50.05%

3. Why is mole concept important?

a. It is useful when converting between grams and atoms or molecules.

b. It gives us a convenient way to express large numbers.

c. It can be applied to any type of particle representative.

d. all of the above

4. What is the SI unit for measurement of number of particles in a substance?

a. kilogram

c. candela

b. ampere

d. mole

5. Avogadro's number is _____.

a. the weight of a carbon atom

c. a mole

b. 6.02 x 1023

d. a dozen
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