Units of Concentration

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Units of Concentration

• The analytical chemists nightmare!

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SI Units
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Concentration Units
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Prefixes
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Calculations

• The Mole Concept
• The amount of substance which contains as many
  entities as there are atoms in 12 grams of 12C.
• One Mole 6.023 x 1023
• Avogadros Number

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Calculations

• Molar Solutions
• xM mass/RMM in 1000ml

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Calculations

• Molar Solutions to gdm-3
• mass xM x RMM in 1000ml

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Calculations

• Molar Solutions to ppm
• 1ppm 1mg per kg
• mass xM x RMM in 1000ml
• mass (g) x 1000 mass (mg)

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Calculations

• Percentage Concentrations

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Calculations

• 10 Ethanol in Water
• 10 (w/v) 10g per 100ml 100g in 1000ml
• 100g / 46.07 2.17M
• 10 (v/v) 10ml per 100ml 100ml in 1000ml
• 100ml x 0.79 79g 79g / 46.07 1.71M
• 10 (w/w) 10g per 100g 100g in 1000g
• 100g / 0.79 126.6ml 126.6 900 1026.6ml
• 100 x 1000/1026.6 97.4g 97.4g / 47.06 2.11M

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Calculations

• Concentration to Molarity
• 1 (w/v) 1g per 100ml 10g in 1000ml
• xM mass/RMM in 1000ml

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Calculations

• Titrations
• MAVA MBVB