An excess of zinc is added to 125 mL of 0.100 M HCl solution, What mass of zinc chloride is formed?
Zn + 2HCl ----> ZnCl2 + H2
0.851743 round to three significant digits would be 0.852 grams of zinc chloride formed too lazy to show calculations
To find the mass of zinc chloride formed, you need to first determine the limiting reagent in the reaction. The limiting reagent is the reactant that is completely consumed first and determines the maximum amount of product that can be formed.
In this case, the reaction between zinc and hydrochloric acid produces zinc chloride and hydrogen gas. The balanced equation is:
Zn + 2HCl → ZnCl2 + H2
From the balanced equation, you can see that the stoichiometric ratio of zinc to zinc chloride is 1:1, meaning that 1 mole of zinc reacts to form 1 mole of zinc chloride.
To find the limiting reagent, you need to compare the number of moles of zinc to the number of moles of hydrochloric acid in the reaction.
First, convert the volume of the hydrochloric acid solution to moles using the molarity:
Volume of HCl solution = 125 mL = 0.125 L
Moles of HCl = Molarity × Volume = 0.100 mol/L × 0.125 L = 0.0125 mol
Now, convert the moles of zinc to moles of zinc chloride:
Moles of Zn = Excess (given as an excess)
Moles of ZnCl2 = Moles of Zn
Since the stoichiometry of the reaction is 1:1, the moles of zinc chloride formed will be the same as the moles of zinc.
Finally, to find the mass of zinc chloride formed, you need to multiply the number of moles by the molar mass of zinc chloride.
Molar mass of ZnCl2 = (atomic mass of Zn) + 2 × (atomic mass of Cl)
= 65.38 g/mol + 2 × 35.45 g/mol
= 136.28 g/mol
Mass of ZnCl2 = Moles of ZnCl2 × Molar mass of ZnCl2
= 0.0125 mol × 136.28 g/mol
= 1.705 g
Therefore, the mass of zinc chloride formed is 1.705 grams.
1.7
moles HCl = M x L = ??
Using the coefficients in the balanced equation, convert moles HCl to moles ZnCl2.
Convert moles ZnCl2 to grams. g = moles x molar mass.