Question

ChemistA
Magnesium reacts with hydrochloric acid according to this equation
Mg + 2HCI - MgCl2 + H2
both Mg and HCl
A scientist combines 2.5 mol of Mg
and 4.0 mol of HCl in a flask. What is
the limiting reagent?
Mg
neither Mg nor HCI
HCI

Answer 1

The limiting reagent : HCl

Further explanation

Given

Mg + 2HCI - MgCl₂ + H₂

2.5 mol of Mg  and 4.0 mol of HCl

Required

the limiting reagent

Solution

A method that can be used to find limiting reactants is to divide the number of moles of known substances by their respective coefficients

mol ratio Mg : HCl =

$\tt \dfrac{2.5}{1}\div \dfrac{4}{2}=2.5\div 2$

HCl as a limiting reagent(smaller ratio)