Question

Масса соляной кислоты, необходимая для получения 67,2 л водорода при взаимодействии с цинком

Answer 1

2Hcl+Zn=ZnCl2+H2
n(H2)=67.2/22.4=3 моль
x=3
2=1
x=6
n(HCl)=6 моль
m(HCl)=6*36.5=219 г

Answer 2

Calculating the Amount of Hydrochloric Acid Needed to Produce 67.2 Liters of Hydrogen

To calculate the amount of hydrochloric acid (HCl) needed to produce 67.2 liters of hydrogen (H2) through its reaction with zinc (Zn), we can use the balanced chemical equation for the reaction:

Zn + 2HCl → ZnCl2 + H2

According to the stoichiometry of this reaction, 1 mole of zinc reacts with 2 moles of hydrochloric acid to produce 1 mole of hydrogen gas. From this, we can calculate the amount of hydrochloric acid needed.

Calculation:

1. Molar Volume of a Gas at STP: The molar volume of a gas at standard temperature and pressure (STP) is 22.4 liters per mole.

2. Moles of Hydrogen Gas: Given that 1 mole of any gas at STP occupies 22.4 liters, the moles of hydrogen gas can be calculated as: \[ \text{moles of H2} = \frac{\text{volume of H2}}{\text{molar volume at STP}} = \frac{67.2}{22.4} \]

3. Moles of Hydrochloric Acid: Since 1 mole of zinc reacts with 2 moles of hydrochloric acid, the moles of hydrochloric acid needed can be calculated as: \[ \text{moles of HCl} = 2 \times \text{moles of H2} \]

4. Mass of Hydrochloric Acid: The molar mass of hydrochloric acid is 36.46 g/mol. Therefore, the mass of hydrochloric acid needed can be calculated as: \[ \text{mass of HCl} = \text{moles of HCl} \times \text{molar mass of HCl} \]

Result:

The mass of hydrochloric acid needed to produce 67.2 liters of hydrogen gas through its reaction with zinc can be calculated using the above steps.

\[ \text{mass of HCl} = 2 \times \left( \frac{67.2}{22.4} \right) \times 36.46 \]

\[ \text{mass of HCl} = 2 \times 3 \times 36.46 = 218.76 \, \text{grams} \]

Therefore, the mass of hydrochloric acid needed is 218.76 grams.