Convert 12.0 g of CO2(44.0 g/mol) to molecules.

1.64 x 10^23 molecules

Explanation:

Amount of moles of CO2 (n) = ?

Mass of NaOH in grams = 12.0g

Molar mass of CO2, use the molar masses of:

Carbon, C = 12g

Oxygen,O = 16g;

CO2 = 12g + (16g x 2)

= 12g + 32g

= 44g/mol

Since, amount of moles = mass in grams / molar mass

n = 12.0g / 44.0g/mol

n = 0.2727 mole

Now based on Avogadro's law:

1 mole of any substance has 6.02 x 10^23 molecules

So, 1 mole of CO2 = 6.02 x 10^23 molecules

0.2727 moles of CO2 = Z

To get the value of Z, cross multiply:

(Z x 1mole) = (6.02 x 10^23 molecules x 0.2727 moles)

Z = 1.64 x 10^23 molecules

Thus, 12.0 g of CO2 has 1.64 x 10^23 molecules

the answer is definitely c.