Answer :
Explanation :
The aluminium and fluorine react to give ionic compound aluminium fluoride.
Aluminium has 1 valence electrons in their shell and fluorine has 7 valence electrons in their shell.
For the complete octet, both aluminium and fluorine exchange valence electrons to form an ionic compound.
The aluminium donates its three valence electrons to three fluorine atoms and they form one
and three
ions.
Electron transfer image is shown below.
Answer: Option (D) is the correct answer.
Explanation:
Enthalpy is defined as the amount of energy needed or removed from a substance. It is represented by
.
Basically, it is the change in enthalpy and it represents the difference between the energy used in breaking bonds and the energy released in formation of bonds in a chemical reaction.
It is also known as heat of reaction. When value of
is positive then it means heat is absorbed in the chemical reaction.
When value of
is negative then it means that heat is released in the chemical reaction.
Whereas entropy means the measure of randomness. It is represented by
. We cannot calculate entropy but we can measure the change in entropy.
Thus, we can conclude that all of the statements regarding the symbol "ΔH" are correct except it that can be called entropy change.