Answer:
Two electrons
Explanation:
According to the octet rule, atoms must bond to each other, sharing electrons among themselves in an attempt to complete their valence shell (last layer of the electrosphere). In other words, an atom becomes stable when it has 8 electrons in its valence shell.
Oxygen atoms have six electrons in their valence shell, so to achieve the stability suggested by the octet rule (eight electrons), these atoms share two electrons, forming one oxygen gas (O₂) molecule.
Answer:
Part A
HCOOH(aq) + NaOH(aq) → HCOONa(aq) + H2O(l)
Part B
ClCH2CH2CO2H(aq) + NaOH(aq) ------> ClCH2CH2CO2Na(aq) + H2O(l)
Explanation:
The reaction between an alkanoic acid and a base is a neutralization reaction. The reaction occurs as follows;
RCOOH + NaOH ----> RCOONa + H2O
We have to note the fact that the net ionic reaction still remains;
H^+(aq) + OH^-(aq) ---> H2O(l)
In both cases, the reaction can occur and they actually do occur as written.
Answer : The concentration of silver ion is, 
Explanation :
Equilibrium constant : It is defined as the equilibrium constant. It is defined as the ratio of concentration of products to the concentration of reactants.
The equilibrium expression for the reaction is determined by multiplying the concentrations of products and divided by the concentrations of the reactants and each concentration is raised to the power that is equal to the coefficient in the balanced reaction.
As we know that the concentrations of pure solids and liquids are constant that is they do not change. Thus, they are not included in the equilibrium expression.
The given equilibrium reaction is,
The expression of 
will be,
![K_{eq}=[Ag^+]^2[S^{2-}]](https://tex.z-dn.net/?f=K_%7Beq%7D%3D%5BAg%5E%2B%5D%5E2%5BS%5E%7B2-%7D%5D)
![2.4\times 10^{-4}=(2.5\times 110^{-1})^2[S^{2-}]](https://tex.z-dn.net/?f=2.4%5Ctimes%2010%5E%7B-4%7D%3D%282.5%5Ctimes%20110%5E%7B-1%7D%29%5E2%5BS%5E%7B2-%7D%5D)
![[S^{2-}]=3.8\times 10^{-3}M](https://tex.z-dn.net/?f=%5BS%5E%7B2-%7D%5D%3D3.8%5Ctimes%2010%5E%7B-3%7DM)
Therefore, the concentration of silver ion is,
b is fastest, having the lowest activation energy (35 kJ) and is an exothermic reaction, releasing energy in the form of heat
c is slowest, having the highest activation energy (55 kJ) and is an endothermic reaction, taking in energy from its surroundings
