Answer:
B) 25g
Explanation:
Every reaction must follow the law of conservation of mass.
Law of conservation of mass:
According to the law of conservation mass, mass can neither be created nor destroyed in a chemical equation.
Explanation:
This law was given by French chemist Antoine Lavoisier in 1789. According to this law mass of reactant and mass of product must be equal, because masses are not created or destroyed in a chemical reaction.
For example:
In given photosynthesis reaction:
6CO₂ + 6H₂O + energy → C₆H₁₂O₆ + 6O₂
there are six carbon atoms, eighteen oxygen atoms and twelve hydrogen atoms on the both side of equation so this reaction followed the law of conservation of mass.
In given example:
Water + sodium chloride → Product
15 g + 10 gram = 25 g
25 g = 25 g
I₂ (g) + Br₂ (g) ↔ 2IBr (g)
Given is Kc = 280 at 150 degree C.
Kc = [IBr]² / [I₂][Br₂]
Initially [IBr] = 0.45 / 2 = 0.225 M
The actual reaction is:
2IBr ↔ I₂ + Br₂, Kc = 1/280 = 0.00357142
In equilibrium,
[IBr] = 0.225 - 2x
[I₂] = x
[Br₂] = x
By substituting the values we get,
K = [I₂] [Br₂] / [IBr]²
0.00357142 = x×x / (0.225 - 2x)²
√(0.00357142) = x / (0.225 - 2x)
0.0597613 (0.225 - 2x) = x
0.01344 - 2 × 0.0597613x = x
(1 + 2 × 0.0597613)x = 0.01344
x = 0.01344 / (1+2 × 0.0597613)
x = 0.01344 / 1.1195226
x = 0.012005
Substituting the values we get,
IBr = 0.225 - 2 × 0.012005 = 0.17698 M
I₂ = x = 0.012005 M
Br₂ = 0.012005 M
