Question

Расчитайте обьём водорода, который выделиться при взаимодействии 80 г кальция с соляной кислатой. Необходимо учесть, что кальция содержит 20% примесей

Answer 1

Дано:
m(Ca с прим.)=80г.
ω%(прим.)=20%
Vm=22,4л./моль
HCI
-----------------------------
V(H₂)-?
1. Определим массу примесей:
ω%(прим.)=m(прим.) ÷m(Ca +прим.)×100%, отсюда
m(прим.)=ω%(прим.)×m(Ca +прим.)÷100%=20%×80г.÷100%=16г.
2. Определим массу чистого кальция:
m(Ca)=m(Ca с прим.)- m(прим.)=80г.-16г= 64г.
3. Определим молярную массу кальция и его количество вещества  кальция в 64г.:
M(Ca)=40г./моль
n(Ca)=m(Ca)÷M(Ca)=64г.÷40г./моль= 1,6моль
3. Запишем уравнение реакции:
Ca + 2HCI=CaCI₂ +H₂
4. Анализируем уравнение реакции: по уравнению реакции из 1моль кальция образуется 1моль водорода, значит из 1,6моль кальция образуется 1,6моль водорода. n(H₂)=1,6моль
5. Определим объем водорода количеством вещества 1,6моль:
V(H₂)=n(H₂)xV(H₂)=1,6мольх22,4л./моль=35,84л.
6. Ответ: образуется 35,84л. водорода.

Answer 2

Calculating the Volume of Hydrogen Gas Produced

To calculate the volume of hydrogen gas produced when 80g of calcium reacts with hydrochloric acid, we need to consider that the calcium contains 20% impurities.

First, we need to find the moles of pure calcium and then use the stoichiometry of the reaction to find the moles of hydrogen gas produced. Finally, we can use the ideal gas law to calculate the volume of hydrogen gas.

1. Calculate Moles of Pure Calcium: - The molar mass of calcium is 40.08 g/mol. - Since the calcium contains 20% impurities, the mass of pure calcium is 80g * (1 - 0.20) = 64g. - Calculate the moles of pure calcium: moles = mass / molar mass.

2. Use Stoichiometry to Find Moles of Hydrogen Gas: - Write the balanced chemical equation for the reaction between calcium and hydrochloric acid. - Use the mole ratio between calcium and hydrogen gas to find the moles of hydrogen gas produced.

3. Calculate the Volume of Hydrogen Gas: - Use the ideal gas law, PV = nRT, where P is the pressure, V is the volume, n is the number of moles, R is the gas constant, and T is the temperature.

Let's calculate each step based on the given information and the chemical equation for the reaction.

Calculation Steps

1. Calculate Moles of Pure Calcium: - Molar mass of calcium (Ca) = 40.08 g/mol. - Mass of pure calcium = 80g * (1 - 0.20) = 64g. - Moles of pure calcium = 64g / 40.08 g/mol.

Calculation: - Moles of pure calcium = 64g / 40.08 g/mol = 1.596 mol.

2. Use Stoichiometry to Find Moles of Hydrogen Gas: - The balanced chemical equation for the reaction is: ``` Ca + 2HCl -> CaCl2 + H2 ``` - According to the balanced equation, 1 mole of calcium produces 1 mole of hydrogen gas.

Calculation: - Moles of hydrogen gas = 1.596 mol.

3. Calculate the Volume of Hydrogen Gas: - Given that the reaction takes place at standard temperature and pressure (STP), the molar volume of an ideal gas at STP is 22.4 L/mol.

Calculation: - Volume of hydrogen gas = moles of hydrogen gas * molar volume at STP. - Volume of hydrogen gas = 1.596 mol * 22.4 L/mol.

Result: - Volume of hydrogen gas = 35.78 L.

Conclusion

The volume of hydrogen gas produced when 80g of calcium, containing 20% impurities, reacts with hydrochloric acid is 35.78 liters at standard temperature and pressure (STP).