If 2 grams of substance A react completely with 3 grams of substance B, what must be true about the products?

2A+IB-3C+ID

A 1 gram of substance B is left over

B. 2 moles of substance A are used

Oc 4 grams of products are produced

D. 4 moles of products are produced

OES grams of products are produced

1 answer

Based on the reaction equation you provided, \( 2A + IB \rightarrow 3C + ID \), we can analyze the situation with the given masses of the reactants (2 grams of substance A and 3 grams of substance B).

To evaluate the options concerning the products:

  1. 1 gram of substance B is left over: This can only be true if B is in excess during the reaction. However, without knowing the molar masses of A and B, we cannot determine if there is leftover B.

  2. 2 moles of substance A are used: This statement addresses the amount used concerning its molar mass. Since we only have mass and no molar mass provided, we cannot confirm this.

  3. 4 grams of products are produced: According to the law of conservation of mass, the total mass of the products must equal the total mass of the reactants. We started with a total of 2 grams of A + 3 grams of B = 5 grams of reactants. Therefore, the products must also total 5 grams. This option is false.

  4. 4 moles of products are produced: Similar to the previous analysis, we cannot verify the moles of products without knowing the molar masses, so this statement cannot be confirmed.

  5. 5 grams of products are produced: Since the mass of the reactants (5 grams) must equal the mass of the products, this statement is true.

So, based on the analysis, option 5 grams of products are produced is the correct answer.