Calculate the mass fraction of tin in a bronze sample, which is obtained by fusing 30 g of tin with 170 g of copper

Mass fraction in percent is the ratio of the mass of the component to the total mass of the sample (solution, etc.), multiplied by 100%. D A (%) = (m A / m total) * 100%.
In our sample of bronze alloy, D Sn (%) = 30: (30 + 170) * 100% = 30/200 * 100% = 15%.

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