Answer:

Explanation:
The expression can be solved mathematically as follows:
1)
Given
2)
Definition of sum
3)
/Associative property
4)
Distributive property
5)
Multiplication
6)
Subtraction.
7)
Multiplication/Associative property
8)
Associative property
9)
/Result
Answer:
Explanation:
exothermic reactions are the reactions which involve the release of energy.
the energy released can be of any forms ,for example heat,light .
all the combustion reactions are exothermic reactions
Consider this balanced chemical equation:
2 H2 + O2 → 2 H2O
We interpret this as “two molecules of hydrogen react with one molecule of oxygen to make two molecules of water.” The chemical equation is balanced as long as the coefficients are in the ratio 2:1:2. For instance, this chemical equation is also balanced:
100 H2 + 50 O2 → 100 H2O
This equation is not conventional—because convention says that we use the lowest ratio of coefficients—but it is balanced. So is this chemical equation:
5,000 H2 + 2,500 O2 → 5,000 H2O
Again, this is not conventional, but it is still balanced. Suppose we use a much larger number:
12.044 × 1023 H2 + 6.022 × 1023 O2 → 12.044 × 1023 H2O
These coefficients are also in the ratio of 2:1:2. But these numbers are related to the number of things in a mole: the first and last numbers are two times Avogadro’s number, while the second number is Avogadro’s number. That means that the first and last numbers represent 2 mol, while the middle number is just 1 mol. Well, why not just use the number of moles in balancing the chemical equation?
2 H2 + O2 → 2 H2O
Answer:
The <u>equilibrium constant</u> is:

Explanation:
The correct equation is:
Thus, with the equilibrium concentrations you can calculate the equilibrium constant, Kc.
The equation for the equilibrium constant is:
![k_c=\dfrac{[NH_3]^2}{[N_2]\cdot [H_2]^3}](https://tex.z-dn.net/?f=k_c%3D%5Cdfrac%7B%5BNH_3%5D%5E2%7D%7B%5BN_2%5D%5Ccdot%20%5BH_2%5D%5E3%7D)
Substituting:


Answer:
Metals on the left of the Periodic Table.
Non-Metals on the top-right, plus Hydrogen.