Ionization energy, also called ionization potential, in chemistry, the amount of energy required to remove an electron from an isolated atom or molecule.
Answer: Option (D) is the correct answer.
Explanation:
Need means necessity without which a person might not be able to survive for long.
For example, food is a need for every living being as without it any individual cannot survive for a long period of time.
Similraly, shelter is also a need and insurance is also necessary as it protects an individuals life or his savings so that after his death the future of his family remains protected.
Whereas cable TV is not a need as an individual can survive without it. Therefore, a cable TV is a want.
Answer : The correct option is, (A) -x kJ/mol
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 chemical reaction is,

Now we have to determine the value of
for the following reaction i.e,

According to the Hess’s law, if we reverse the reaction then the sign of
change.
So, the value
for the reaction will be:


Hence, the value of
for the reaction is -x kJ/mole.
Hey there,
Answer:
Photosynthetic cell
Hope this helps :D
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