Answer:
C
Explanation:
A - Crude oil is composed for hundreds of hydrocarbon, not less than ten.
B - Is formed in specific conditions of temperature and pressure
C - It's fractionated to form gasoline, lubricants, CH4, plastics and many other products made of hydrocarbon.
D - We have crude oil located more than 4000 yards below the surface in countries like Brazil
E - The crude oil is very thick and don't have an specific usage, so we need to refine it.
Answer:
b
Explanation:
A pure substance has a constant composition and cannot be separated into simpler substances by physical means. There are two types of pure substances: elements and compounds.
During the Physical changes
Generally speaking, organic molecules tend to dissolve in solvents that have similar physical properties. A good rule of thumb is that "like dissolves like". Meaning, polar compounds can dissolve polar compounds and nonpolar compounds can dissolve nonpolar compounds.
To apply this to the current problem, we are told that the brushes are being cleaned with vegetable oil or mineral oil. In this case, the oils are used as solvents. In order for these solvents to be effective, the compounds they are trying to dissolve must be similar in structure and properties to other oils. Therefore, vegetable oil or mineral oil will be most effective in removing oil-based paints, as these will have the similar properties needed to dissolve in the oil solvents.
