i think it is 8. I might be wrong.
Do you know what is meant by needed? does it mean lone pairs?
Answer: The correct option is 1.
Explanation: Endothermic reactions are the reactions in which heat is provided to break down the reactant molecules.
In option 1:
The stronger intermolecular forces between the particles in solid molecule are broken down to convert into gaseous form. Hence, some energy in the form of heat is provided to move them far apart. Therefore, it is considered as an endothermic reaction.
In option 2, 3 and 4:
All the other processes involves the formation of bonds and thus there is no need to provide any energy.
Answer:
South American
Explanation:
When you look at a map of plates, only South American forms a boundary with the African plate out of those specific plates
A mixture is composed of more than one substance combined
A pure substance cannot be decomposed in any reaction
<span>Both are considered types of substances
</span>hope it helps you playa!
