A. 74% Fe
B. 75% Fe
C. 77% Fe
D. 78% Fe
¨ To calculate the percent of iron in the ore, we need to first determine the mass of oxygen present in the compound. We can do this by subtracting the mass of iron from the total mass of the compound:
¨ Mass of oxygen = Total mass of the compound – Mass of iron Mass of oxygen = 35.8 g – 27.9 g Mass of oxygen = 7.9 g
¨ Now, we can calculate the percent of iron in the ore by dividing the mass of iron by the total mass of the compound and multiplying by 100:
¨ Percent iron = (Mass of iron / Total mass of the compound) x 100 Percent iron = (27.9 g / 35.8 g) x 100 Percent iron = 77.9%
¨ Therefore, the correct answer is (C) 77% Fe, which is the closest option to the calculated value of 77.9%.
Submitted by :- Jamil Ahmed