Answer:
B. Coal
Explanation: Coal is mined to produce energy.
Answer:
B. liquid to gas
Explanation:
Matter exists in 3 different states:
- Solid: in solids, particles in the substance are tightly bond to each other through strong intermolecular forces. Therefore, they can only vibrate around their fixed position, but they cannot move freely: as a result, the distance between the particles is the smallest among the 3 states of matter.
- Liquid: in a liquid, particles are able to slide past each other, however there are still intermolecular forces keeping them not too far from each other. As a result, in liquids, particles are on average more distance from each other compared to solids.
- Gas: in a gas, particles are completely free to move, as the intermolecular forces between them are negligible. As a result, in gases, the distance between molecules is the greatest, compared with solids and liquids.
Therefore, the phase changes in which the average distance between molecules increases is:
B. liquid to gas
Answer:
AlF₃ is Lewis Acid
CH₃F is Lewis Base
Explanation:
According to Lewis concept ,"those compounds which donate pair of electrons are called as Lewis Base and those accepting pair of electrons are called as Lewis Acid.
In Given Reaction,
<span> AlF</span>₃<span> + CH</span>₃<span>F → CH</span>₃⁺<span> + [AlF</span>₄<span>]</span>⁻
AlF₃ is acting as acid because the octet of Al is not complete, hence it has tendency to accept electrons.
CH₃F is acting as a base because the F atom containing three lone pair of electrons can donate it to Al metal resulting in the formation of electrophile i.e. CH₃⁺.