Answer:
0.214 L
Explanation:
Step 1: Write the balanced equation
This is a single displacement reaction.
Zn(s) + 2 HCl(aq) ⇒ ZnCl₂(aq) + H₂(g)
Step 2: Calculate the moles corresponding to 0.625 g of Zn
The molar mass of Zn is 65.38 g/mol.
0.625 g × 1 mol/65.38 g = 9.56 × 10⁻³ mol
Step 3: Calculate the moles of H₂ produced from 9.56 × 10⁻³ moles of Zn
The molar ratio of Zn to H₂ is 1:1. The moles of H₂ produced are 1/1 × 9.56 × 10⁻³ mol = 9.56 × 10⁻³ mol.
Step 4: Calculate the volume occupied by 9.56 × 10⁻³ moles of hydrogen
Assuming standard pressure and temperature, 1 mole of hydrogen occupies 22.4 L.
9.56 × 10⁻³ mol × 22.4 L/1 mol = 0.214 L
Answer:
38.0 g C2F3Cl3) / (187.3756 g C2F3Cl3/mol) x (3 mol Cl / 1 mol C2F3Cl3) x (35.4532 g Cl/mol) =
21.6 g Cl in C2F3Cl3
To determine the amount of each solution that she should use, we do mass balance for the whole process. We let x be the amount the 65% salt and y the amount of the 90% salt. We do as follows:
The total mass should be equal to 150 oz.
x + y = 150
Doing a salt balance, we obtain the second equation:
.65x + .90y = 150(.85)
Solving for x and y, we obtain:
x = 30 oz
y = 120 oz
