5. Correct subscripts are essential for correctly writing a chemical formula

True

False

6. How many atoms of oxygen are there in 5 mol of CO₂?

6 x 1024 atoms

10 atoms

6 x 1023 atoms

3 x 1024 atoms

5 atoms

7. Which has more atoms, 1 mol of helium or 1 mol of argon?

The number of atoms cannot be determined

The mol of He has more atoms

They both have the same number of atoms

The mol of Ar has more atoms

8. A 115 g sample of dry ice, CO₂, contains how many moles?

4.11 mol

28.0 mol

2.61 mol

5.06 x 103 mol

44.0 mol

3.22 x 103 mol

9. Given a 6.25 mol sample of Ag, how many atoms are present? Give your answer to the correct number of sig figs and use e or *10^ for entering your answer in scientific notation.

10. Given the following imaginary elements and average atomic masses, calculate the molar mass of the compound AX₂R₃ to two decimal places.

Symbol	Ave. Atomic Mass
A	32.39
D	93.80
R	17.79
X	22.68

11. How many nanomoles (nmol) is a 59.5 microgram (g) sample of sulfur? Give your answer to 3 sig figs AND in scientific notation.