what is the percentage of calcium in a sample if a 0.50g sample of unkown contains...

Question

Question

what is the percentage of calcium in a sample if a 0.50g sample of unkown contains .20g ca?

science chemistry

Answer 1

Answer #1

Mass of Ca = 0.20 g

Mass of sample = 0.50 g

Use:

Mass % of Ca = mass of Ca * 100 / mass of sample

= 0.20 * 100 / 0.50

= 40. %

Answer: 40. %

Answer 2

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