Molar volume of a gas template

A-level / AP / IB (CBSE class 11): magnesium ribbon and excess dilute HCl in a conical flask; the hydrogen goes through a delivery tube into an inverted burette full of water, clamped in a trough. Room temperature and pressure are recorded.

What the template shows

• Measure the volume of hydrogen from a weighed piece of magnesium
• One-hole bung
• Drop the Mg into the acid and put the bung in at once
• Mg ribbon + excess dilute HCl
• About 0.04 g of cleaned, weighed Mg in 25 cm³ of 1 mol dm⁻³ HCl. Mg + 2HCl → MgCl₂ + H₂. No flames nearby
• Inverted burette
• Full of water at the start. The scale reads upside down: volume of H₂ = start reading − end reading
• Record the conditions
• Room temperature and pressure. Molar volume = V(H₂) ÷ n(Mg), about 24 dm³ mol⁻¹ at room temperature and pressure; AP: subtract the water vapour pressure first
• Trough of water
• A gas syringe in place of the burette reads the volume directly
• Reaction setup

Drawn with 16 shapes – every one editable in MolDraw.

Sources

• Atkins, de Paula & Keeler, Atkins' Physical Chemistry, 11th ed., OUP 2018 Textbook