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Relative Formula Mass expressed in grams. The relative formula mass of a molecule or compound can be expressed in grams . The relative formula mass measured in grams is called one mole of the substance. Calculate relative formula masses and express them in grams.
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Relative Formula Mass expressed in grams • The relative formula mass of a molecule or compound can be expressed in grams. • The relative formula mass measured in • grams is called one mole of the substance.
Calculate relative formula masses andexpress them in grams Hydrogen Chloride HCl 36.5 g Carbon Dioxide CO2 44 g 63 g Nitric Acid HNO3 Sodium Carbonate Na2CO3 106 g
The relative formula mass of all gases expressed in grams has a certain volume Volume = 22.4 dm3 at 0oC Volume = 24 dm3 at 20oC 1 dm3 (=1 litre) is about the size of a very big glass of water
Here are examplesMassVolume 2 g H2 gas = 24 dm3 (22.4 dm3) 44 g CO2 gas = 24 dm3 (22.4 dm3) 16 g O2 gas = 12 dm3 (11.2 dm3) 34 g NH3 gas = 48 dm3 (44.8 dm3)
Calculating masses when given volumes(use 24 dm3)VolumeMass 3 dm3 Oxygen gas = 4 g 7 g 6 dm3 Nitrogen gas = 142 g 48 dm3 Chlorine gas = 66 g 36 dm3 Carbon Dioxide =
Using balanced equations The big numbers in front of the reactants and products in balanced chemical equations show the reacting ratios. H2 + O2 = H2O 2 2 2(1x2)g H2 + 1(2x16)g O2 = 2(1x2+16)g H2O 4g H2 + 32g O2 = 36g H2O 48 dm3 H2 + 24 dm3 O2 = 48 dm3 H2O
Calculate the ratio of atoms in compounds from supplied masses or % composition(empirical formulae) Sodium Oxide Sodium 46g Oxygen 16g Sodium 23 46/23 = 2 Oxygen 16 16/16 = 1 Formula for Sodium Oxide Na2O