Calculations with equations involving solutions
2 marks · EasyCalculate the number of moles of potassium chloride, KCl, dissolved in 15 cm³ of solution with a concentration of 0.25 mol/dm³.
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0.0038 mol (±0.0003)
Also accept: 3.75 × 10^{-3} mol; 0.00375 mol
Common mistakes: Not converting cm³ to dm³ (divide by 1000)
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Marking points
M1 · 1 mark · Converts volume from cm³ to dm³ before multiplying
A1 · 1 mark · Correct final number of moles of KCl, with acceptable rounding (follow-through)
Worked solution
Convert 15 cm³ to dm³: 15 / 1000 = 0.015 dm³
Rounded to two significant figures: 0.0038 mol