calculate the mass in grams of hydrogen chloride produced when 5.25 L of a molecular hydrogen measured at STP reacts with an excess of molecular chlorine gas
H2 + Cl2 ==> 2HCl
Convert 5.25L Cl2 to mols. L/22.4 = mols.
Convert mols Cl2 t mols HCl using the coefficients in the balanced equation.
Convert mols HCl to grams. g = mols x molar mass.
To calculate the mass of hydrogen chloride produced, we need to follow a few steps:
Step 1: Determine the balanced chemical equation for the reaction between molecular hydrogen (H2) and molecular chlorine (Cl2) to form hydrogen chloride (HCl).
The balanced equation for this reaction is:
H2 + Cl2 -> 2HCl
This equation tells us that two moles of hydrogen chloride are produced for every one mole of molecular hydrogen and one mole of molecular chlorine.
Step 2: Convert the volume of molecular hydrogen (H2) to moles using the ideal gas law.
The ideal gas law equation is:
PV = nRT
Where:
P = pressure (STP conditions have a pressure of 1 atm)
V = volume in liters
n = number of moles
R = ideal gas constant (0.0821 L·atm/(mol·K))
T = temperature in Kelvin (STP conditions have a temperature of 273.15 K)
Using the given volume of 5.25 L and the STP conditions, we can calculate the number of moles of molecular hydrogen:
n(H2) = (P * V) / (R * T)
= (1 atm * 5.25 L) / (0.0821 L·atm/(mol·K) * 273.15 K)
= 0.231 moles
Step 3: Determine the moles of hydrogen chloride (HCl) produced using the balanced chemical equation.
According to the balanced equation, for every 1 mole of H2, 2 moles of HCl are produced.
Therefore, the number of moles of HCl produced is:
n(HCl) = 2 * n(H2)
= 2 * 0.231 moles
= 0.462 moles
Step 4: Convert moles of hydrogen chloride to grams using the molar mass of HCl.
The molar mass of hydrogen chloride (HCl) is:
Atomic mass of H = 1 g/mol
Atomic mass of Cl = 35.5 g/mol
Molar mass of HCl = 1 g/mol + 35.5 g/mol = 36.5 g/mol
Therefore, the mass of hydrogen chloride produced is:
Mass (HCl) = n(HCl) * molar mass (HCl)
= 0.462 moles * 36.5 g/mol
= 16.837 grams
So, the mass of hydrogen chloride produced is approximately 16.837 grams.