Answer:
The equilibrium concentration of NO is 0.02124 M.
Explanation:
Given that,
Initial concentration of NOBr = 0.878 M

Temperature = 24°C
We know that,
The balance equation is

Initial concentration is,

Concentration is,

Equilibrium concentration

We need to calculate the value of x
Using formula of concentration
![k_{c}=\dfrac{[NO][Br_{2}]}{[NOBr]^2}](https://tex.z-dn.net/?f=k_%7Bc%7D%3D%5Cdfrac%7B%5BNO%5D%5BBr_%7B2%7D%5D%7D%7B%5BNOBr%5D%5E2%7D)
Put the value into the formula
![3.07\times10^{-4}=\dfrac{[2x][x]}{[0.878-2x]^2}](https://tex.z-dn.net/?f=3.07%5Ctimes10%5E%7B-4%7D%3D%5Cdfrac%7B%5B2x%5D%5Bx%5D%7D%7B%5B0.878-2x%5D%5E2%7D)





We need to calculate the equilibrium concentration of NO
Using formula of concentration of NO

Put the value of x


Hence, The equilibrium concentration of NO is 0.02124 M.
Answer:
option b. B3+
Explanation:
Boron takes the 5th position on the periodic table, therefore it has 5 electrons....2 on the inside and 3 on the outside. when it lost it 3 external electrons, it become positively charged with the amount of electron it loses.
You'll want to add three amounts of heat.
(1) Specific heat of lowering the temperature from -135°C to the melting point -114°C
(2) Latent heat of fusion/melting
(3) Specific heat of elevating the temperature from -114°C to -50°C
(1) E = mCΔT = (25 g)(0.97 J/g·°C)(1 kJ/1000 J)(-114 - -135) = 0.509 kJ
(2) E = mΔH = (25 g)(5.02 kJ/mol)(1 mol/46.07 g ethanol) = 2.724 kJ
(3) E = mCΔT = (25 g)(2.3 J/g·°C)(1 kJ/1000 J)(-50 - -114) = 3.68 kJ
<em>Summing up all energies, the answer is 6.913 kJ.</em>