Question

How many molecules of CH4 are in 48.2 g of this compound? A) 2.00 x 1023 B) 5.00 x 10-24 C)1.81 x 1024 D) 4.00 E) 4.64 x 1026 10) -

Answer 1

Answer: The correct answer is Option C.

Explanation:

To calculate the number of moles, we use the equation:

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$

Given mass of methane = 48.2 g

Molar mass of methane = 16 g/mol

Putting values in above equation, we get:

$\text{Moles of }CH_4=\frac{48.2g}{16g/mol}=3.0125mol$

According to mole concept:

1 mole of compound contains $6.022\times 10^{23}$ number of molecules.

So, 3.0125 moles of methane will contain = $3.0125\times 6.022\times 10^{23}18.141\times 10^{23}=1.81\times 10^{24}$ number of molecules.

Hence, the correct answer is Option C.