Question

What mass of SiF4 could be produced by the reaction of 15 g of SiO2 with an excess of HF? The equation for the reaction is: SiO2 + 4HF ® SiF4 + 2H2O

1.04 g 12 g 26 g 104 g

Answer 1

To find the mass of SiF4 produced, we calculate the moles of SiO2 given (15 g) and then use the mole ratio from the balanced equation to find the corresponding mass of SiF4. The correct answer is 26 g.

Step-by-step explanation:

Calculating the Mass of SiF4 Produced

To calculate the mass of SiF4 that could be produced from 15 g of SiO2 reacting with an excess of HF, we use the balanced chemical equation SiO2 + 4HF → SiF4 + 2H2O. We first calculate the molar mass of SiO2, which is approximately 60.08 g/mol, and then use stoichiometry to determine the amount of SiF4 produced. Assuming a complete reaction and that HF is in excess, the mass of SiF4 produced directly relates to the initial mass of SiO2.

For SiO2 reacting with HF, there is a 1:1 molar ratio between SiO2 and SiF4. Therefore, 15 g of SiO2 corresponds to 15 g / 60.08 g/mol = 0.2495 mol of SiO2. This produces the same amount in moles of SiF4. Given the molar mass of SiF4 approximately 104 g/mol, the theoretical mass of SiF4 produced is 0.2495 mol x 104 g/mol = 25.948 g, which we would round to 26 g. Therefore, the correct answer from the given choices is 26 g.