How many liters of hydrogen gas can be produced as 295k and 99.0 kPa if 22.3 grams of potassium metal react with excess water?
2K + H20 = 2KOH + H2
You didn't balance the equation so I have done that.
2K + 2H20 = 2KOH + H2
mols K metal = grams/atomic mass = 22.3/39.1 = 0.570
The equation tells you with the coefficients aht 2 mols K will produce 1 mol H2 gas; therefore, 0.570 mols K will produce0.570/2 mols = ?
Then PV = nRT. You know P and n and R (8.314 if you use kPa), and T is 295 K. Solve for V in liters. Post your work if you get stuck
I think I have the correct answer, but would the answer be 6.50 L of hydrogen gas?
NOPE. I'll find the error if you show you set up and the math.
To find the number of liters of hydrogen gas produced, we can use the ideal gas law equation.
The ideal gas law equation is given as:
PV = nRT
Where:
P = pressure (in kilopascals, kPa)
V = volume (in liters, L)
n = number of moles
R = ideal gas constant (0.0821 L·atm/mol·K or 8.314 J/mol·K)
T = temperature (in Kelvin, K)
First, we need to calculate the number of moles of hydrogen gas produced. We can use the stoichiometry of the balanced chemical equation to do this.
From the balanced chemical equation:
2 moles of potassium (K) react with 2 moles of KOH and produce 1 mole of hydrogen gas (H2)
Given that 22.3 grams of potassium (K) react, we can calculate the number of moles of potassium:
Molar mass of potassium (K) = 39.1 g/mol
Number of moles of potassium (K) = Mass / Molar mass
Number of moles of potassium (K) = 22.3 g / 39.1 g/mol
Next, we use the stoichiometry of the balanced chemical equation to find the number of moles of hydrogen gas produced:
According to the balanced equation: 2 moles of potassium (K) produce 1 mole of hydrogen gas (H2)
Number of moles of hydrogen gas (H2) = Number of moles of potassium (K) / (2 moles of potassium (K) : 1 mole of hydrogen gas (H2))
Now, with the number of moles of hydrogen gas, we can use the ideal gas law equation to find the volume (in liters) of hydrogen gas produced. Rearranging the equation to solve for V, we have:
V = (nRT) / P
Given that the temperature is 295 K and the pressure is 99.0 kPa, we can substitute the values into the equation and solve for V:
V = (number of moles of hydrogen gas) x (Ideal gas constant) x (temperature in Kelvin) / (pressure in kPa)
By substituting the known values, we can calculate the volume (V) in liters.