Question

Определите объем выделившегося газа если прореагировало 3 грамма цинка и 3 литра соляной кислоты. Срочно

Answer 1

2HCl + 2Zn =  2ZnCl + H2
n(HCl) = 3/22,4 = 0,13 моль
M(Zn) = 65
n(Zn) = 3/65 = 0,046 моль
Цинк в недостатке, значит будем решать через него.
Из соотношения видим, что водорода в два раза меньше, чем цинка. Значит, 
n(H2)=n(Zn)/2 = 0,023 моль
V(H2)=0,023 x 22,4 = 0,52 дм3

Answer 2

Calculation of the Volume of Gas Evolved

To determine the volume of gas evolved when 3 grams of zinc reacts with 3 liters of hydrochloric acid (HCl), we need to consider the stoichiometry of the reaction. The balanced chemical equation for the reaction between zinc and hydrochloric acid is as follows:

Zn + 2HCl → ZnCl2 + H2

According to the balanced equation, 1 mole of zinc reacts with 2 moles of hydrochloric acid to produce 1 mole of hydrogen gas. To calculate the volume of gas evolved, we need to convert the mass of zinc to moles and then use the mole ratio to determine the number of moles of hydrogen gas produced. Finally, we can convert the moles of hydrogen gas to volume using the ideal gas law.

1. Convert the mass of zinc to moles: - The molar mass of zinc (Zn) is approximately 65.38 g/mol. - Therefore, 3 grams of zinc is equal to 3/65.38 = 0.0459 moles of zinc.

2. Use the mole ratio to determine the moles of hydrogen gas produced: - According to the balanced equation, 1 mole of zinc produces 1 mole of hydrogen gas. - Therefore, 0.0459 moles of zinc will produce 0.0459 moles of hydrogen gas.

3. Convert moles of hydrogen gas to volume: - The ideal gas law equation is PV = nRT, where P is the pressure, V is the volume, n is the number of moles, R is the ideal gas constant, and T is the temperature. - Assuming the reaction takes place at standard temperature and pressure (STP), which is 0 degrees Celsius (273.15 Kelvin) and 1 atmosphere (101.325 kilopascals), we can use the following values: - P = 1 atm - R = 0.0821 L·atm/(mol·K) - T = 273.15 K - Plugging in these values, we can solve for V: - V = (nRT)/P = (0.0459 mol * 0.0821 L·atm/(mol·K) * 273.15 K) / 1 atm = 1.084 L

Therefore, the volume of gas evolved when 3 grams of zinc reacts with 3 liters of hydrochloric acid is approximately 1.084 liters.