Answer:
0.124% of Cr2O3 in the sample
Explanation:
A mass percent is expressed as 100 times the ratio of the mass of analyte and the mass of the sample. For this problem, the equation is:
Mass Cr2O3(g) / Mass Mineral(g) * 100
To solve this question we must convert the mass of Cr2O3 to grams and then, compute the value in the equation:
Mass Cr2O3 in g:
0.560mg * (1g / 1000mg) = 5.6x10⁻⁴g Cr2O3
Percent of Cr2O3 is:
5.6x10⁻⁴g Cr2O3 / 0.45g * 100
0.124% of Cr2O3 in the sample
