A researcher at an agricultural institute in Kenya analysed a sample of irrigation water. The water contained 0.0050 mol of dissolved calcium sulfate (CaSO₄) in 500 cm³.
What is the concentration of calcium sulfate in the water in mol/dm³?

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Question

A researcher at an agricultural institute in Kenya analysed a sample of irrigation water. The water contained 0.0050 mol of dissolved calcium sulfate (CaSO₄) in 500 cm³.
What is the concentration of calcium sulfate in the water in mol/dm³?

Accepted Answer

0.010 mol/dm³ — 010 mol/dm³). Award 1 mark for correct calculation. 500 cm³ = 0.500 dm³. Concentration = moles ÷ volume = 0.0050 ÷ 0.500 = 0.010 mol/dm³. A is incorrect — this multiplies moles by volume instead of dividing. C is incorrect — this uses 50 cm³ instead of 500 cm³. D is incorrect — this divides 0.0050 by 0.002 instead of 0.500.

Answer

0.0025 mol/dm³

Answer

2.5 mol/dm³

Answer

0.10 mol/dm³

Answer

0.010 mol/dm³

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