A piece of zinc with a mass of 0.100 g reacts with 20.0 mL of 6.0 M HCl at a temperature of 25 C and a pressure of 750 mm Hg in 600 seconds. Calculate the average rate at which the hydrogen gas is produced in mL/sec.
rate = moles H2 produced/600 sec = ??
To calculate the average rate at which the hydrogen gas is produced, we need to determine the amount of hydrogen gas generated and divide it by the time taken.
First, let's calculate the number of moles of zinc (Zn) using its mass and molar mass.
The molar mass of zinc (Zn) is approximately 65.38 g/mol.
Number of moles of Zn = Mass of Zn / Molar mass of Zn
Number of moles of Zn = 0.100 g / 65.38 g/mol
Next, let's determine the number of moles of hydrogen gas (H₂) produced. According to the balanced chemical equation, 1 mole of zinc reacts with 2 moles of HCl to produce 1 mole of hydrogen gas.
Number of moles of H₂ = Number of moles of Zn
Since the reaction stoichiometry states that 1 mole of zinc produces 1 mole of hydrogen gas, we have:
Number of moles of H₂ = Number of moles of Zn
Now let's calculate the volume of hydrogen gas (H₂) produced. Using the ideal gas law, we can relate the number of moles of hydrogen gas to its volume. The ideal gas law equation is:
PV = nRT
Where:
P = pressure (in atm)
V = volume (in liters)
n = number of moles of gas
R = ideal gas constant (0.0821 L·atm/mol·K)
T = temperature (in Kelvin)
First, let's convert the pressure from mm Hg to atm:
Pressure (in atm) = 750 mm Hg * (1 atm / 760 mm Hg)
Next, convert the temperature from Celsius to Kelvin:
Temperature (in Kelvin) = 25°C + 273.15
Now we can rearrange the ideal gas law equation to solve for volume (V):
V = nRT / P
Calculate the volume of hydrogen gas produced using the known values.
Lastly, we need to determine the average rate of hydrogen gas production by dividing the volume of gas produced by the time taken.
Average rate of hydrogen gas production = Volume of H₂ / Time taken
Substitute the known values and solve for the average rate of hydrogen gas production.