There are 7.11 x1024molecules in 100.0 cm3of a certain substance. a. what is the number of molecules in 1.09 cm3of the substance? 7.75 x 1022moleculesb. what is the number of molecules in 2.24 x 104cm3of the substance? 1.59 x 10 27moleculesc. what number of molecules would be in 9.01 x 10-6cm3? 6.41 x 1017molecules

a. 7.75 × 10²² molecules

b. 1.59 × 10²⁷ molecules

c. 6.41 × 10¹⁷ molecules

Explanation:

There are 7.11 × 10²⁴ molecules in 100.0 cm³ of a certain substance. We will use this ratio in our conversion fractions.

a. What is the number of molecules in 1.09 cm³ of the substance?

1.09 cm³ × (7.11 × 10²⁴ molecules/100.0 cm³) = 7.75 × 10²² molecules

b. What is the number of molecules in 2.24 × 10⁴ cm³ of the substance?

2.24 x 10⁴ cm³ × (7.11 × 10²⁴ molecules/100.0 cm³) = 1.59 × 10²⁷ molecules

c. What number of molecules would be in 9.01 × 10⁻⁶ cm³?

9.01 × 10⁻⁶ cm³ × (7.11 × 10²⁴ molecules/100.0 cm³) = 6.41 × 10¹⁷ molecules