The molar mass of CaCl2

Question

is 110.98g/mol. How many molecules of CaCl2
are there in 4g?(1 point)
Responses

5.426×1021
molecules
5 point 4 2 6 times 10 to the 21th power molecules

2.170 × 1022
molecules
2.170 × 1022
molecules

2.409×1024
molecules
2 point 4 0 9 times 10 to the 24th power molecules

2.673×1026
molecules

Answer 1

To determine how many molecules of CaCl₂ are in 4 g of the compound, we can follow these steps:

1. Find the number of moles of CaCl₂ in 4 g using the molar mass: \[ \text{Number of moles} = \frac{\text{mass (g)}}{\text{molar mass (g/mol)}} \] \[ \text{Number of moles} = \frac{4 , \text{g}}{110.98 , \text{g/mol}} \approx 0.0360 , \text{moles} \]

2. Convert moles to molecules using Avogadro's number (\(6.022 \times 10^{23}\) molecules/mole): \[ \text{Number of molecules} = \text{Number of moles} \times \text{Avogadro's number} \] \[ \text{Number of molecules} = 0.0360 , \text{moles} \times 6.022 \times 10^{23} , \text{molecules/mole} \approx 2.170 \times 10^{22} , \text{molecules} \]

Therefore, the answer is: 2.170 × 10²² molecules.