When zinc metal is reacted with hydrochloric acid, zinc chloride and hydrogen gas are produced. If 16.4 ml of 2.14 M HCl are used:

a) how many grams of zinc metal are needed to completely use up the acid?

b) What will be the molarity of the aqueous product?

Please show all work. Thank you!

I wont show all work, ever. What teacher would ever do that?

balance the equation
Zn+ 2HCl>>ZnCl2 (aq) + H2(g)
so for each mole of acid, you need half that moles of Zn.

moles HCL: Volume*concentraioninMolarity
moles of Zn needed: half of that.
grams of Zn: molesZn*atomicmassZn
Molarity of product? it is a solution of ZincChloride: figure the moles of ZnCl2 made (same moles as Zn), then
molarityZnCl2= molesZnCl2/volume
where volume is still .0164 liters.

This is a regular stoichiometry problem.

Zn + 2HCl ==> ZnCl2 + H2

1. Convert HCl to moles. moles = M x L = ?
2. Use the coefficients in the balanced equation to convert moles HCl to moles Zn.
3. Convert moles Zn to grams. g = moles to molar mass.

b) Convert moles (either Zn or HCl) to moles ZnCl2. Then M = moles/L.

Thank you both for your help! You made it very clear

To find the answer to each part of the question, we need to use the stoichiometry of the reaction. The balanced equation for the reaction between zinc metal (Zn) and hydrochloric acid (HCl) is:

Zn + 2HCl → ZnCl2 + H2

a) To determine the mass of zinc metal needed to react completely with the given amount of hydrochloric acid, we first need to calculate the number of moles of HCl used. To do this, we'll use the formula:

moles = volume (in L) × concentration (in mol/L)

Given that the volume is 16.4 mL and the concentration is 2.14 M, we convert the volume to liters by dividing by 1000:

moles of HCl = 16.4 mL / 1000 mL/L × 2.14 mol/L
= 0.035096 mol

From the balanced equation, we know that 1 mole of zinc metal reacts with 2 moles of hydrochloric acid. Therefore, the moles of zinc metal required would be half of the moles of HCl used:

moles of Zn = 0.035096 mol / 2
= 0.017548 mol

To calculate the mass of zinc metal, we need to use the molar mass of zinc, which is 65.38 g/mol:

mass of Zn = moles of Zn × molar mass of Zn
= 0.017548 mol × 65.38 g/mol
= 1.149 g (rounded to three decimal places)

Therefore, approximately 1.149 grams of zinc metal are needed to completely use up the hydrochloric acid.

b) To find the molarity of the aqueous product (zinc chloride), we need to calculate the moles of zinc chloride formed and then divide it by the volume of the aqueous solution.

From the balanced equation, we can see that 1 mole of zinc chloride is produced for every mole of zinc reacted. So, the moles of ZnCl2 formed is also 0.017548 mol.

To find the volume in liters, we need to convert 16.4 mL to liters by dividing by 1000:

volume of solution = 16.4 mL / 1000 mL/L
= 0.0164 L

Finally, we can calculate the molarity using the formula:

molarity = moles / volume

molarity of ZnCl2 = 0.017548 mol / 0.0164 L
= 1.071 M (rounded to three decimal places)

Therefore, the molarity of the aqueous product (zinc chloride) is approximately 1.071 M.