Question

1. the calculation of quantities in a chemical reaction is called stoichiometry. otrue ofalse 23) the molar mass is the mass of one mole of a pure substance. otrue ofalse 24) the international system of units to measure the amount of a substance is called a mole. otrue ofalse 25) in the following equation, what is the ratio of hydrogen molecules to water molecules? 2 h2 + o2 --> 2 h2o a) 1:1 b) 2:2 c) 2:1 26) what is the first step in a stoichiometry problem?

Explanation:

1. Stoichiometry is indeed the calculation of quantities in a chemical reaction.
2. By definition, molar mass is the mass of one - mole of a pure substance.
3. The mole is the SI unit for the amount of a substance.
4. In the chemical equation \(2H_2 + O_2

ightarrow2H_2O\), the coefficient of \(H_2\) is 2 and the coefficient of \(H_2O\) is 2, so the ratio of hydrogen molecules to water molecules is \(2:2\) which simplifies to \(1:1\).

Answer:

1. True
2. True
3. True
4. A. 1:1