Answer:
1) Fe = 69.9%
O = 31.1%
2) H = 5.19%
O = 16.5%
N = 28.9%
C = 49.5%
Explanation:
One easy way to do percent compositions is to assume you have 100g of a substance.
1) Lets say we have 100g of Fe2O3.
The total molar mass would be:

The molar mass of the Fe2 alone is:

Thus, the grams of Fe2(out of a 100) could be calculated by multiplying 100g * the molar mass ratio of Fe2 to the whole:

Which is approximately 69.9%.
We can find the amount of O3 by simply subtracting, as the rest of the compound is made of O3. Thus, the % composition of O3 is 31.1%
You can then do this same process to the next question, getting us the following:
H = 5.19%
O = 16.5%
N = 28.9%
C = 49.5%
Answer:
- <u><em>butylphenyl ether.</em></u>
Explanation:
The formula of the compound is:
- CH₃ - CH₂ - CH₂ - CH₂ - O - C₆H₅
1. The functional group is of the kind R - O - R', i.e. two alkyl groups each attached to one end of the oxygen atom. That means that the compound is an ether.
2. One group attached to the oxygen group is CH₃ - CH₂ - CH₂ - CH₂ - which has 4 carbons and is named butyl group.
3. The other group attached to the oxygen atom is C₆H₅ - which is derived from ciclohexane as is known as phenyl group.
4. Using the rule of naming the subtituents in alphabetical order, you name butyl first and phenyl second, so it is <u><em>butylphenyl ether.</em></u>
Answer:

look at the picture above
Answer:
B. The amounts of water and alcohol are not the same
Explanation:
11.
С7Н16 + 11О2 --> 8Н2О + 7СО2