Answer:
carbon nitrogen and oxygen
<u>Answer:</u>
<em>1) ∆H is positive
Endothermic
</em>
<em>2)
Endothermic </em>
<em>3) Energy is absorbed
Endothermic
</em>
<em>4)
Exothermic
</em>
<em>5) ∆H is negtive
Exothermic
</em>
<em></em>
<u>Explanation:</u>
∆H is called as enthalpy change
It is also called as Heat of reaction
Energy is required for the bond to break a bond.
Energy is released when a bond is formed.

that is

We see in this equation, bonds between hydrogen and chlorine molecules gets broken and on the right side bond is formed in HCl.
If energy of products greater than energy of reactants then the reaction enthalpy change is endothermic .
If energy of products lesser than energy of reactants then the reaction enthalpy change is exothermic .
For example



(positive hence endothermic)



(negative hence exothermic)
The correct answer is option D, that is, a storage battery is charged using an electric current.
The transformation of one form of energy into another, generally to transform the energy into more useful kind is known as energy conversion. The energy can neither be created nor be destroyed, it can only be transformed. The different forms of energy comprise light, heat, mechanical, electrical, sound, nuclear, and sound.
In the given question, the charging of a storage battery using electric current is an example of electrical energy being converted into chemical energy.
Answer:
The mass of
in the container is 2.074 gram
Explanation:
Given:
Volume of
lit
Equilibrium constant 
The reaction in which
is produced
⇄ 
Here equal moles of
and
is formed.
From the formula of equilibrium constant,


M
Above value shows,

So in 2 L no. moles of
=
moles.
So mass of 0.122 mole of
is =
g
Therefore, the mass of
in the container is 2.074 gram