If a Cu-bearing material weighing 40g yield 5g Cuo(mw.76.55) the percentage of Cu (at.wt.63.55) in the sample is:
Correct answer: A. (5x63.55/76.55)/40x100
- A. (5x63.55/76.55)/40x100
- B. 40/5x79.55/63.x100
- C. 5/40x79.55/63.55x100
- D. 25/40x100
Explanation
To find the percentage of copper (Cu) in the sample, we can use the formula:Percentage of Cu = (Mass of Cu / mass of sample) × 100Given that:Mass of Cu = 5gMass of sample = 40gSubstituting the values into the formula:Percentage of Cu = (5g / 40g) × 100= 5/40×100
This question appeared on the ETEA MDCAT 2010 paper, which you can sit online with every answer explained.
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