Compound.
Because compound is a substance formed by a chemical reaction of two or more separate elements. If a compound is separated, it would become two or more different substances instead of similar ones.
Wish this helps.
Bella from BOC Sciences
The answer is (4) CH3CH2OH and CH3OCH3. You need to figure out which pair has the same molecular formula which means that they have the same number of same atoms. Then you can get the write answer.
The fuel released 90 calories of heat.
Let suppose that water experiments an entirely <em>sensible</em> heating. Hence, the heat released by the fuel is equal to the heat <em>absorbed</em> by the water because of principle of energy conservation. The heat <em>released</em> by the fuel is expressed by the following formula:
(1)
Where:
- Mass of the sample, in grams.
- Specific heat of water, in calories per gram-degree Celsius.
- Temperature change, in degrees Celsius.
If we know that
,
and
, then the heat released by the fuel is:

The fuel released 90 calories of heat.
We kindly invite to check this question on sensible heat: brainly.com/question/11325154
The acids found in alcohol that make it evaporate are called organic acids.
An organic acid is an organic compound that has acidic properties. There are two types: one has a carboxyl (COOH) group, and the other type has a phenol group.
The most common organic acids are those with a carboxyl group and include acetic acid, formic acid, lactic acid and all fatty acids. Perfumes include organic acid in their composition to make them volatile. Volatile substances evaporate easily, and this is important for perfumes. They need to dissipate easily into the surrounding environment and spread their good smell.