If in an experiment we're working with Mg, HCl acid, and H20. We stick the magnesium in the acid mixed with water and the Mg dissolves.
One of the products is hydrogen gas. If the water in the tube is evaporated, the other product, a white salt remains. Write a balanced chemical equation for this reaction.
What is the molar relationship between the solid Mg and the H2 gas?
Mg + 2 HCl -> MgCl2 + H2
The reaction as written tells you that the molar ratio is one mole of H2 gas produced per mole of Mg consumed.
how do you solve mole ratios?
To solve mole ratios, you typically look at the coefficients in the balanced chemical equation. In this case, the balanced chemical equation is:
Mg + 2 HCl -> MgCl2 + H2
The coefficients in the equation represent the relative number of moles of each compound involved in the reaction.
In the balanced equation, the coefficient in front of Mg is 1, which means that 1 mole of Mg is consumed. The coefficient in front of H2 is also 1, which means that 1 mole of H2 gas is produced.
Therefore, the molar relationship between the solid Mg and the H2 gas is 1:1. For every 1 mole of Mg consumed, 1 mole of H2 gas is produced.