Matter can be broken down into two categories: pure substances and mixtures. Pure substances are further broken down into elements and compounds. Mixtures are physically combined structures that can be separated into their original components. A chemical substance is composed of one type of atom or molecule.
The balanced reaction is:
4Fe + 3O2 --> 2Fe2O3
Stoichiometrically:
(1.0 mol Fe)(2 mol Fe2O3 / 4 mol Fe) = 0.50 mol Fe2O3
If the actual yield is only 0.325 mol Fe2O3, the % yield can be calculated by dividing actual by theoretical yield:
0.325 / 0.5 x 100% = 65% yield
Answer:
They use hypotheses to guess a result based on what they already know. Observations are used to record the results of an experiment. Predictions are used to have an expected outcome of a test, thinking the hypothesis is correct. Experiments are used to test the hypothesis.
<span>0.032000000 cg
Rounding off ........>
0.0320 cg
The last zero means the measurement is accurate to that digit
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