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Concentration. Concentration. Particles per volume Can be in grams per litre but chemists usually express concentration in moles per litre This are related by the formula: Where: n = moles V = volume in litres c = concentration in molL -1. Write the formula for:
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Concentration Particles per volume Can be in grams per litrebut chemists usually express concentration in moles per litre This are related by the formula: Where: n = moles V = volume in litres c = concentration in molL-1
Write the formula for: 1. Moles using mass and Molar mass 2. Concentration using Volume and Moles
Concentration Example 15 grams of NaCl is dissolved in 1 litre of water, what is the concentration of the solution in moles per litre? (M NaCl = 58.5 gmol-1) Find moles of NaCl Divide moles by volume in litres
Concentration Example 20 grams of NaOH is dissolved in 500mls of water, what is the concentration of the solution in moles per litre? (M NaOH = 40gmol-1) Find moles of NaOH Divide moles by volume in litres
Have a go • Calculate the concentration of 18.0g of glucose (C6H12O6) dissolved in 200ml of solution.
n=m/Mr • n=18.0g/180gmol-1 • n=0.100mol • c=n/V • c=0.100mol/0.200L • c=0.500molL-1