They have 6 electron in their outer orbital. That means they want 2 electrons to be stable. Since metals have the tendency to give electron oxygen receives 2 electrons. The answer is -2
Answer:
B is most volatile, A is least volatile
Explanation:
We are given with the equilibrium constant of acid, HF and is asked to calculate the pH of 0.30 M NaF solution. The formula to be followed is
Ka = [H+][F-]/[HF]Ka = 7.2 x 10 -4 = x^2/[0.3-x]x = [H+]= pH = -log (H+) = 1.84
Answer : The standard enthalpy of formation of ethylene is, 51.8 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 formation reaction of 
will be,
The intermediate balanced chemical reaction will be,
(1) 
(2) 
(3) 
Now we will reverse the reaction 1, multiply reaction 2 and 3 by 2 then adding all the equations, we get :
(1) 
(2) 
(3) 
The expression for enthalpy of formation of will be,
Therefore, the standard enthalpy of formation of ethylene is, 51.8 kJ/mole
Answer:
Na⁺ tends to interact with the hardest base, which is water. Ag⁺ tends to interact with the softest (hardless) base, which is Cl⁻.
Explanation:
The HSAB concept says that hard acids are small ions with low electronegativity, while hard bases are electron donating groups with high electronegativity and low polarizability. The HSAB concept also says that hard acids will tend to react with hard bases. The opposite is valid for soft acids and soft bases.
Na⁺ is a hard acid
Ag ⁺ is a soft acid
Cl⁻ is a hard base
H₂O is a harder base than Cl⁻
Therefore, when in water, the Na⁺ tends to react with water, because it is a harder base than Cl⁻. However, as Ag⁺ is a soft acid, it will tend to stay with the less hard base, which is Cl⁻.
