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 48 48 96 96 24 24 16
24 grams of reactant A should be present initially.
To find this, first calculate the molar mass of A2B:
A2B = A + A + B = 12 + 12 + 4 = 28 g/mol
Then, calculate the molar ratio of A to A2B from the balanced chemical equation:
4A + B2 → 2A2B
4 mol A = 2 mol A2B
1 mol A = 0.5 mol A2B
Now, calculate the number of moles needed to produce 112g of A2B:
112g / 28 g/mol = 4 mol A2B
Finally, convert the required moles of A2B to moles of A, using the molar ratio:
4 mol A2B x 1 mol A / 0.5 mol A2B = 8 mol A
Calculate the mass of A needed to produce 8 moles:
8 mol A x 12 g/mol = 96g
Therefore, 96g of reactant A should be present initially.