A 230 g sample of a compound contains 136.6 g of carbon, 26.4 g of hydrogen, and 31.8 g of nitrogen. The rest is oxygen. What is the mass percent of oxygen in the compound?
230-136.6-26.4-31.8 = 35.2
35.2/230 = 0.153 = 15.3%
A 1.00 g sample of naphthalene (C10H8) contains 0.562 g of hydrogen. What is the mass percent of carbon in the compound
15.3%
To find the mass percent of oxygen in the compound, we need to calculate the mass of oxygen and the total mass of the compound.
Given that the sample contains 230 g of the compound, and the masses of carbon, hydrogen, and nitrogen are 136.6 g, 26.4 g, and 31.8 g, respectively, we can find the mass of oxygen by subtracting the sum of the masses of carbon, hydrogen, and nitrogen from the total mass of the compound:
Mass of oxygen = Total mass of the compound - (Mass of carbon + Mass of hydrogen + Mass of nitrogen)
Mass of oxygen = 230 g - (136.6 g + 26.4 g + 31.8 g)
Mass of oxygen = 230 g - 194.8 g
Mass of oxygen = 35.2 g
So, the mass of oxygen in the compound is 35.2 g.
To calculate the mass percent of oxygen, we divide the mass of oxygen by the total mass of the compound and multiply by 100:
Mass percent of oxygen = (Mass of oxygen / Total mass of the compound) × 100
Mass percent of oxygen = (35.2 g / 230 g) × 100
Mass percent of oxygen ≈ 15.30%
Therefore, the mass percent of oxygen in the compound is approximately 15.30%.