Alex drips hydrochloric acid onto a 5.9 g piece of magnesium in a single displacement reaction. How many molecules of HCl are required? 2HCl(aq) + Mg(s) → MgCl2(aq) + H2(g) how do you do this?

2.96 × 10²³ molecules is required if Alex drips hydrochloric acid onto a 5.9 g piece of magnesium in a single displacement reaction

According to this question, hydrochloric acid (HCl) reacts with magnesium metal (Mg) to produce magnesium chloride and hydrogen has as follows:

2HCl(aq) + Mg(s) → MgCl2(aq) + H2(g)

Where; Mg = 24g/mol

mole = 5.9/24

mole = 0.246mol of Mg

To convert mole to number of molecules, we multiply number of moles by 6.02 × 10²³ (Avogadro's no.)

Hence, number of molecules of HCl required is 0.492mol × 6.02 × 10²³

= 2.96 × 10²³ molecules of HClHCl

Learn more:

a. energy is absorbed in the reaction.

if in a given reaction the energy of products is greater than the energy of reactants it means that reaction is endothermic and during the reaction, the energy is absorbed by reactants. in an endothermic reaction, the products have more stored chemical energy than the reactants. and in this reaction the reactants are more stable than products before the compounds with less energy are always more stable.