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
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