<u>Answer:</u> The concentration of hydrogen gas at equilibrium is 0.0275 M
<u>Explanation:</u>
Molarity is calculated by using the equation:

Moles of HI = 0.550 moles
Volume of container = 2.00 L

For the given chemical equation:

<u>Initial:</u> 0.275
<u>At eqllm:</u> 0.275-2x x x
The expression of
for above equation follows:
![K_c=\frac{[H_2][I_2]}{[HI]^2}](https://tex.z-dn.net/?f=K_c%3D%5Cfrac%7B%5BH_2%5D%5BI_2%5D%7D%7B%5BHI%5D%5E2%7D)
We are given:

Putting values in above expression, we get:

Neglecting the negative value of 'x' because concentration cannot be negative
So, equilibrium concentration of hydrogen gas = x = 0.0275 M
Hence, the concentration of hydrogen gas at equilibrium is 0.0275 M
Answer:
0.033 M
Explanation:
Let's consider the neutralization reaction between NaOH and HCl.
NaOH + HCl → NaCl + H₂O
0.4 L of 0.1 M NaOH were used. The reacting moles of NaOH are:
0.4 L × 0.1 mol/L = 0.04 mol
The molar ratio of NaOH to HCl is 1:1. The reacting moles of HCl are 0.04 moles.
0.04 moles of HCl are in 1.2 L. The molarity of HCl is:
M = 0.04 mol / 1.2 L = 0.033 M
The concept of atomic masses we can find that the correct answer is:
c) 101
The atomic mass or mass number of an element is the sum of its protons plus the neutrons that are in the atomic nucleus, the electrons are not taken into account because they have a mass much lower than the masses of protons and neutrons.
In the table they indicate that there are 46 protons and 55 neutrons, therefore
M = #_ {protons} + #_ {neutrons}
M = 46 +55
M = 101
In conclusion using the concept of atomic masses we find that the correct answer is:
c) 101
Learn more about atomic mass here:
brainly.com/question/1317964