Question

Determine the number of molecules of CCl₄ contained in 70.3 g of CCl₄.

A. 2.5 x 10²³ molecules
B. 6.02 x 10²³ molecules
C. 1.5 x 10²⁴ molecules
D. 3.01 x 10²³ molecules

Answer 1

To find the number of CCl₄ molecules in 70.3 g, calculate the molar mass of CCl₄, convert grams to moles, and then use Avogadro's number to convert moles to molecules, resulting in 3.01 x 10²³ molecules.

Step-by-step explanation:

To determine the number of molecules of CCl4 contained in 70.3 g of CCl4, we use the molar mass of CCl4 to convert grams to moles and then use Avogadro's number to convert moles to molecules. The molar mass of CCl4 is calculated by summing the atomic masses of one carbon atom (C, approximately 12.01 g/mol) and four chlorine atoms (Cl, approximately 35.45 g/mol each).

First, calculate the molar mass of CCl4:
Molar mass of CCl4 = 12.01 g/mol (for C) + 4 x 35.45 g/mol (for Cl) = 153.81 g/mol.

Now, calculate the number of moles in 70.3 g of CCl4:
Moles of CCl4 = 70.3 g / 153.81 g/mol.

Then, use Avogadro's number to find the number of molecules:
Number of molecules = Moles of CCl4 x 6.022 x 1023 molecules/mol.

Therefore, when you perform these calculations, you'll find the correct answer to be Option D: 3.01 x 1023 molecules.