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Answer:
Heating is the best method
Explanation:
When a mass of crystals containing Water of crystallization is heated sufiiciently to a high temperature, water vapor may be driven off the crystals by the action of heat alone.
<u>Answer:</u> The value of equilibrium constant is 0.997
<u>Explanation:</u>
We are given:
Percent degree of dissociation = 39 %
Degree of dissociation,
= 0.39
Concentration of
, c = 
The given chemical equation follows:

<u>Initial:</u> c -
<u>At Eqllm:</u>

So, equilibrium concentration of ![N_2O_4=c-c\alpha =[1-(1\times 0.39)]=0.61M](https://tex.z-dn.net/?f=N_2O_4%3Dc-c%5Calpha%20%3D%5B1-%281%5Ctimes%200.39%29%5D%3D0.61M)
Equilibrium concentration of ![NO_2=2c\alpha =[2\times 1\times 0.39]=0.78M](https://tex.z-dn.net/?f=NO_2%3D2c%5Calpha%20%3D%5B2%5Ctimes%201%5Ctimes%200.39%5D%3D0.78M)
The expression of
for above equation follows:
![K_{c}=\frac{[NO_2]^2}{[N_2O_4]}](https://tex.z-dn.net/?f=K_%7Bc%7D%3D%5Cfrac%7B%5BNO_2%5D%5E2%7D%7B%5BN_2O_4%5D%7D)
Putting values in above equation, we get:

Hence, the value of equilibrium constant is 0.997
Answer:
228
Explanation:
alpha decay is removing alpha particle 
2 number of protons, 4 mass number = 2 protons + 2 neutrons
We have
90 protons and 142 neutrons
<u> - 2 protons - 2 neutrons</u>
88 protons 140 neutrons
Mass number of new (daughter) atom = 88 +140 = 228