what mass of H2(g) is produced from the reaction of 5.2g Fe(s) with excess hydrochloric acid?
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To determine the mass of H2(g) produced, we first need to balance the chemical equation for the reaction between Fe(s) and hydrochloric acid (HCl). The balanced equation is as follows:
Fe(s) + 2HCl(aq) → FeCl2(aq) + H2(g)
From the balanced equation, we can see that 1 mole of Fe(s) reacts with 2 moles of HCl(aq) to produce 1 mole of H2(g). Now, let's calculate the number of moles of Fe(s) used.
Mass of Fe(s) = 5.2g
Molar mass of Fe = 55.845 g/mol (from periodic table)
Number of moles of Fe(s) = Mass of Fe(s) / Molar mass of Fe
= 5.2g / 55.845 g/mol
= 0.093 moles (approx)
Since the reaction is balanced in a 1:2 ratio, the number of moles of H2 produced is also 0.093 moles.
Now, let's calculate the mass of H2(g) produced.
Molar mass of H2 = 2.016 g/mol (from periodic table)
Mass of H2(g) = Number of moles of H2 × Molar mass of H2
= 0.093 moles × 2.016 g/mol
= 0.187 g (approx)
Therefore, approximately 0.187 grams of H2(g) will be produced from the reaction.
To find the mass of H2(g) produced from the reaction between 5.2g Fe(s) and excess hydrochloric acid, we need to follow a few steps:
Step 1: Write a balanced chemical equation for the reaction:
Fe(s) + 2HCl(aq) -> FeCl2(aq) + H2(g)
The balanced equation shows that 1 mole of Fe reacts with 2 moles of HCl to produce 1 mole of FeCl2 and 1 mole of H2.
Step 2: Convert the given mass of Fe into moles. To do this, we use the molar mass of iron (Fe), which is 55.85 g/mol.
moles of Fe = mass of Fe / molar mass of Fe
moles of Fe = 5.2 g / 55.85 g/mol
Step 3: Determine the limiting reactant. Since hydrochloric acid (HCl) is given as excess, Fe is the limiting reactant.
Step 4: Use the stoichiometry from the balanced equation to find the moles of H2 produced. From the balanced equation, we know that 1 mole of Fe reacts to produce 1 mole of H2.
moles of H2 = moles of Fe
Step 5: Convert the moles of H2 back to mass using the molar mass of hydrogen (H2), which is 2.02 g/mol.
mass of H2 = moles of H2 x molar mass of H2
Now, let's calculate:
moles of Fe = 5.2 g / 55.85 g/mol = 0.093 mol
moles of H2 = 0.093 mol
mass of H2 = 0.093 mol x 2.02 g/mol ≈ 0.188 g
Therefore, approximately 0.188 grams of H2 gas will be produced from the reaction.