You have to do another test to record the differences.
Answer is: empirical formula is Fe₂O₃.
m(Fe) = 7,50 g.
m(iron oxide) = 10,71 g.
n(Fe) = m(Fe) ÷ M(Fe).
n(Fe) = 7,50 g ÷ 55,85 g/mol = 0,134 mol.
m(O) = m(iron oxide) - m(Fe).
m(O) = 10,71 g - 7,50 g = 3,21 g.
n(O) = 3,21 g ÷ 16 g/mol = 0,20 mol.
n(Fe) : n(O) = 0,134 mol : 0,2 mol = 2 : 3.
A quantitative observation must be a measurement of some sort. (Something including numbers). Qualitative, on the other hand, is when you are using words to describe what has happened.
Answer:
i would assume that it would be (a)
Explanation:
The Sun generates its energy by nuclear fusion
NUCLEAR FISSION is when the heavy atom is split
fusion energy is scientifically feasible. Plasma conditions that are very close to those required in a fusion reactor are now routinely reached in experiments
mass gets lost is nuclear fusion
so (a) is the most accurate
1 lb=453.592 grams
So he gained 453.592 pounds
