Answer : The value of 
for the reaction is, -135.2 kJ
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 of 
will be,
The intermediate balanced chemical reaction will be,
(1) 
(2) 
(3) 
We are dividing the reaction 1, 2 and 3 and reversing reaction 3 and then adding all the equations, we get :
(1) 
(2) 
(3) 
The expression for enthalpy of formation of will be,
Therefore, the value of for the reaction is, -135.2 kJ
Answer:
16.86%
Explanation:
Na3N is sodium nitride.
% of N = mass of N/ molar mass of Na3N *100
% of N = 14/83*100= 16.86%
The equilibrium means that amount that are coming equals the amount that are going.
So the correct answers are
2. A person's income and expenses are equal every month.
3. The pressure exerted on the inside of a balloon by the gas inside is equal to the pressure exerted on the outside of the balloon by the atmosphere.
-Hiadamcom/From Agarvated
Answer:
1.4952 grams of sodium bicarbonate she would need to ingest to neutralize this much HCl.
Explanation:
Moles of hydrochloric acid = n
Volume of hydrochloric acid solution = 200.0 mL = 0.200 L
Molarity of the hydrochloric acid = 0.089 M
of HCL
According to reaction, 1 mole of HCl is neutralized by 1 mole of sodium bicarbonate.
Then 0.0178 moles of HCl wil be neutralized by :
of sodium bicarbonate
Mass of 0.0178 moles of sodium bicarbonate:
0.0178 mol × 72 g/mol = 1.4952 g
1.4952 grams of sodium bicarbonate she would need to ingest to neutralize this much HCl.
The correct answer is (3)
I-131 and P-32
The explanation:
according to attached table:
- we can see that the half life of p 32 is 14.28d (more than one hour)
- and the half life of I-131 is 8.021 d
(more than one hour)
and They both have β- decay mode and with half-lives greater than hour.
