|
Description of Action |
Action |
| 1.
Write the formula for the given compound. |
FeBr2 |
| 2.
Record the amount of each element in the compound. Multiply the amount
of each element by its atomic weight (Atomic weights should be rounded
to the tenths place). Add the results to find the gram formula mass
of the compound. |
Fe:
1 x 55.8 = 55.8
Br: 2 x 79.9 = 159.8
215.6 g/mol
|
| 3. Divide the
mass of each element by the total gram formula mass. For these calculations
your answer should have 3 places after the decimal. |
Fe:
55.8 ÷ 215.6 = 0.259
Br: 159.8 ÷ 215.6 = 0.741
|
| 4.
Instead of multiplying our results by 100 to find a percentage, we
will multiply our result by the given mass. Our results are in grams.
(Note: To check your work, add your two masses. It should equal your
given mass.) |
Fe:
0.259 x 45.6 = 11.8 grams
Br: 0.741 x 45.6 = 33.8 grams
45.6 grams
|
