The inner core has the greatest pressure.
The balanced chemical equation for reaction of
and
is as follows:

From the balanced chemical equation, 2 mol of
reacts with 1 mol of
.
First calculating number of moles of
as follows:

On rearranging,

Here, M is molarity and V is volume. The molarity of
is given 0.274 M or mol/L and volume 155 mL, putting the values,

Since, 1 mol of
reacts with 2 mol of
thus, number of moles of
will be
.
Now, molarity of
is given 0.305 M or mol/L thus, volume can be calculated as follows:

Therefore, volume of
is 278.5 mL.
Answer:
About 0.0940 M.
Explanation:
Recall that NaOH is a strong base, so it dissociates completely into Na⁺ and OH⁻ ions. Because the acid is monoprotic, we can represent it with HA. Thus, the reaction between HA and NaOH is:

Using the fact that it took 15.00 mL of NaOH to reach the endpoint, determine the number of HA that was reacted with:

Therefore, the molarity of the original solution was:
![\displaystyle \left[ \text{HA}\right] = \frac{0.00188\text{ mol}}{20.00\text{ mL}} \cdot \frac{1000\text{ mL}}{1\text{ L}} = 0.0940\text{ M}](https://tex.z-dn.net/?f=%5Cdisplaystyle%20%5Cleft%5B%20%5Ctext%7BHA%7D%5Cright%5D%20%3D%20%5Cfrac%7B0.00188%5Ctext%7B%20mol%7D%7D%7B20.00%5Ctext%7B%20mL%7D%7D%20%5Ccdot%20%5Cfrac%7B1000%5Ctext%7B%20mL%7D%7D%7B1%5Ctext%7B%20L%7D%7D%20%3D%200.0940%5Ctext%7B%20M%7D)
In conclusion, the molarity of the unknown acid is about 0.0940 M.
Answer: The overall chemical reaction is exothermic is the correct statement.
Explanation: As seen from the given image, the reactants are at higher energy level and products are at lower energy level and the excess energy is released in the form of heat. These reactions are considered as exothermic reactions.
Hence, the reaction given in the image is an exothermic reaction.
Nitrous acid<span> dissociates as follows:
</span>
HNO₂(s) ⇄ H⁺(aq) + NO₂⁻(aq)
According to the equation, an acid constant has the following form:
Ka = [H⁺] × [NO₂⁻ ] / [HNO₂]
From pH, we can calculate the concentration of H⁺ and NO₂⁻:
[H⁺] = 10^-pH = 10^-2.63 = 0.00234 M = [NO₂⁻]
Now, the acid constant can be calculated:
Ka = 0.00234 x 0.00234 / 0.015 = 3.66 x 10⁻⁴
And finally,
pKa = -log Ka = 3.44