A given sample of chalk contains 55% by mass of calcium carbonate. Cal...
Calculation of Percentage of Calcium, Carbon and Oxygen in Chalk SampleGiven: Mass percentage of Calcium Carbonate in the chalk sample = 55%
To Find:Percentage of Calcium, Carbon and Oxygen in the sample
Solution:Let us assume a 100g sample of chalk.
Mass of calcium carbonate in the sample = 55g
Calculation of Mass of Calcium, Carbon and Oxygen in the Sample:Mass of Calcium = Atomic Mass of Calcium * Number of moles of Calcium
Atomic Mass of Calcium = 40.08 g/mol
Number of moles of Calcium = (Mass of Calcium Carbonate * Mass percentage of Calcium in Calcium Carbonate) / (Atomic Mass of Calcium * Mass percentage of Calcium Carbonate) = (55 * 40.08 * 0.4) / (100 * 55) = 0.08016 g
Therefore, Mass of Calcium in the sample = 0.08016 g
Mass of Carbon = Atomic Mass of Carbon * Number of moles of Carbon
Atomic Mass of Carbon = 12.01 g/mol
Number of moles of Carbon = (Mass of Calcium Carbonate * Mass percentage of Carbon in Calcium Carbonate) / (Atomic Mass of Carbon * Mass percentage of Calcium Carbonate) = (55 * 12.01 * 0.12) / (100 * 55) = 0.01224 g
Therefore, Mass of Carbon in the sample = 0.01224 g
Mass of Oxygen = Atomic Mass of Oxygen * Number of moles of Oxygen
Atomic Mass of Oxygen = 16 g/mol
Number of moles of Oxygen = (Mass of Calcium Carbonate * Mass percentage of Oxygen in Calcium Carbonate) / (Atomic Mass of Oxygen * Mass percentage of Calcium Carbonate) = (55 * 16 * 0.48) / (100 * 55) = 0.1392 g
Therefore, Mass of Oxygen in the sample = 0.1392 g
Calculation of Percentage of Calcium, Carbon and Oxygen in the Sample:Percentage of Calcium = (Mass of Calcium / Total Mass of Sample) * 100 = (0.08016 / 100) * 100 = 0.08016%
Percentage of Carbon = (Mass of Carbon / Total Mass of Sample) * 100 = (0.01224 / 100) * 100 = 0.01224%
Percentage of Oxygen = (Mass of Oxygen / Total Mass of Sample) * 100 = (0.1392 / 100) * 100 = 0.1392%
Answer:The percentage of Calcium, Carbon and Oxygen in the given sample of chalk are as follows:
Percentage of Calcium = 0.08016%
Percentage of Carbon = 0.01224%
Percentage of Oxygen = 0.1392%