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Moles, volume and density. 22.4 L. Calculate the volume of a given mass of a gaseous substance from its density at a given temperature and pressure. Include: molar volume calculation Solve problems requiring interconversions between moles, mass, volume, and number of particles.
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Moles, volume and density 22.4 L
Calculate the volume of a given mass of a gaseous substance from its density at a given temperature and pressure. • Include: molar volumecalculation • Solve problems requiring interconversions between moles, mass, volume, and number of particles. • Additional KEY Terms • STP
Avogardo (1776-1856) Avogadro’s Hypothesis - any sample of anygasat the same temperature and pressure will contain the same number of particles.
Chemists use a standard temperature and pressure, STP, to measure gas volumes. 0°C and 101.3 kPa At STP: The volume of 1 mole of ANY GAS is 22.4 L. 22.4 L/mol is known as molar volume. The MASS of 22.4 L of any gas is equal to the molar mass for that gas.
How many moles are in 50.0 L of Fluorine gas at STP? F2 = 36.0 g/mol 1 mol 22.4 L 50.0 L = 2.23 mol
What is the STP volume of 10.0 g of Methane gas? CH4 = 16.0 g/mol 1 mol 22.4 L 1 mol 16.0 g 10.0 g = 14.0 L
Density: A physical property that describes the mass per unit volume of a substance. grams (g) per litre grams per mL (or cm3)
Calculate the volume, in litres, of one mole of ammonia (NH3) at room temperature if the density is 0.696 g/L. 17. 0 g 1 L 0.696 g 1 mol NH3 = 17.0 g/mol 1 mol = 24.4 L
Calculate the volume, in litres, of two moles of carbon dioxide, at room temperature, when the density is 1.80 g/L. 44. 0 g 1 L 1.80 g 1 mol CO2 = 44.0 g/mol 2 mol = 48.9 L
· STP: 0°C and 101.3 kPa (1 atm) · At STP, the molar volume of any gas is 22.4 L · Molar mass = total grams in 1 mole (g/mol) · 1 mole = 6.02 x 1023particles(Avogadro) · density of a substance = mass per volume (g/L) * All roads lead to moles (convert to moles first).
CAN YOU / HAVE YOU? • Calculatethe volume of a given mass of a gaseous substance from its density at a given temperature and pressure. • Include: molar volumecalculation • Solve problems requiring interconversions between moles, mass, volume, and number of particles. • Additional KEY Terms • STP