Elements A and B react according to the following equation:
4A+B2→2A2B
The molar mass of A is 12g/mol. The molar mass of B is 4g/mol. The molar mass of A2B
is 28g/mol. When the goal of the reaction is to produce 112g of the product, how many grams of reactant A should be present initially?
(1 point)
Responses
16
16
24
24
48
48
96
48
To solve this problem, we need to first calculate the molar ratio between A and A2B in the reaction equation.
From the balanced equation, we can see that 4 moles of A react with 1 mole of B2 to produce 2 moles of A2B.
Next, we need to calculate the molar mass ratio between A and A2B. The total molar mass of A and B2 is 12g/mol + 8g/mol = 20g/mol, and the molar mass of A2B is 28g/mol. Therefore, the molar mass ratio of A to A2B is 20g/mol:28g/mol = 5:7.
By combining the molar ratio and molar mass ratio, we find that 20g of A reacts with 28g of A2B. To produce 112g of A2B, we need 80g of A.
Therefore, the answer is 48g of reactant A should be present initially.