Question

CAN SOMEONE PLEASE HELP ME WITH THIS QUESTIONWrong or inproper answer will be reported

Answer 1

The mass of unreacted zinc = 13 g

Further explanation

The reaction equation is the chemical formula of reactants and products

A reaction coefficient is a number in the chemical formula of a substance involved in the reaction equation. The reaction coefficient is useful for equalizing reactants and products

Reaction

$\tt Zn+2HCl\Rightarrow ZnCl_2+H_2$

mol ratio Zn : HCl = 1 : 2

• mol of HCl

$\tt mol=V\times M\\\\mol=0.1~L(100~cm^3)\times 2~mol/L\\\\mol=0.2$

• mol of Zn

$\tt \dfrac{1}{2}\times 0.2=0.1~mol$

• the mass of reacted Zn  :

$\tt 0.1\times 65=6.5~g$

• the mass of unreacted Zn

$\tt 19.5-6.5=\boxed{\bold{13~g}}$