To determine the volume of hydrogen gas produced at STP (Standard Temperature and Pressure) when 2.36 grams of magnesium (Mg) reacts, we need to use stoichiometry and the ideal gas law.
First, let's calculate the number of moles of magnesium using its molar mass:
Molar mass of Mg = 24.3 g/mol
Moles of Mg = 2.36 g / 24.3 g/mol ≈ 0.097 moles
From the balanced equation, we can see that the stoichiometric ratio between magnesium and hydrogen is 1:1. This means that for every 1 mole of magnesium reacted, 1 mole of hydrogen gas is produced.
Therefore, the number of moles of hydrogen gas produced is also 0.097 moles.
Using the ideal gas law, we can relate the number of moles of a gas to its volume at STP:
PV = nRT
P = pressure (at STP, P = 1 atm) V = volume of gas n = number of moles R = ideal gas constant (0.0821 L·atm/(mol·K)) T = temperature (at STP, T = 273.15 K)
Rearranging the equation to solve for V:
V = (nRT) / P
Substituting the values into the equation:
V = (0.097 moles) * (0.0821 L·atm/(mol·K)) * (273.15 K) / 1 atm
V ≈ 2.26 liters
Therefore, approximately 2.26 liters of hydrogen gas will be produced at STP when 2.36 grams of magnesium reacts.
J.R. S.
05/17/23