Answer:
4. Option C. Pentane.
5. Option D.
Explanation:
4. Hydrocarbons are compound containing carbon and hydrogen only. Hydrocarbons are said to be saturated when they contain only carbon to carbon single bond. All alkanes are saturated hydrocarbon.
The correct answer is pentane.
5. Isomerism is the phenomenon whereby two or more compounds have the same molecular formula but different structural patterns. The compounds involved are called isomers.
A careful observation of the diagram above shows that only option D satisfied the definition of Isomerism as the two compound both have the same molecular formula as C3H8O but different structural patterns.
Note: option C does not contain isomers as Isomerism can not occur in a compound having just 1 carbon atom.
Answer:
no no no who are these some look good but are black what is this
Answer : The enthalpy of the reaction is, -2552 kJ/mole
Explanation :
According to Hess’s law of constant heat summation, the heat absorbed or evolved in a given chemical equation is the same whether the process occurs in one step or several steps.
According to this law, the chemical equation can be treated as ordinary algebraic expression and can be added or subtracted to yield the required equation. That means the enthalpy change of the overall reaction is the sum of the enthalpy changes of the intermediate reactions.
The given enthalpy of reaction is,

The intermediate balanced chemical reactions are:
(1)

(2)

(3)

(4)

Now we have to revere the reactions 1 and multiple by 2, revere the reactions 3, 4 and multiple by 2 and multiply the reaction 2 by 2 and then adding all the equations, we get :
(when we are reversing the reaction then the sign of the enthalpy change will be change.)
The expression for enthalpy of the reaction will be,



Therefore, the enthalpy of the reaction is, -2552 kJ/mole
Answer:
C
The answer is C pleaaaaaaase