Answer:
Endothermic
Explanation:
The temperature of the water decreased.
The water lost heat.
The heat must have gone into getting the KNO₃ into solution.
So, the dissolving of KNO₃ in water is endothermic.
The pH of the solution is 2.54.
Explanation:
pH is the measure of acidity of the solution and Ka is the dissociation constant. Dissociation constant is the measure of concentration of hydrogen ion donated to the solution.
The solution of C₆H₂O₆ will get dissociated as C₆HO₆ and H+ ions. So the molar concentration of 0.1 M is present at the initial stage. Lets consider that the concentration of hydrogen ion released as x and the same amount of the base ion will also be released.
So the dissociation constant Kₐ can be written as the ratio of concentration of products to the concentration of reactants. As the concentration of reactants is given as 0.1 M and the concentration of products is considered as x for both hydrogen and base ion. Then the
![K_{a}=\frac{[H^{+}][HB] }{[reactant]}](https://tex.z-dn.net/?f=K_%7Ba%7D%3D%5Cfrac%7B%5BH%5E%7B%2B%7D%5D%5BHB%5D%20%7D%7B%5Breactant%5D%7D)
[HB] is the concentration of base.


Then
![pH = - log [x] = - log [ 0.283 * 10^{-2}]\\ \\pH = 2 + 0.548 = 2.54](https://tex.z-dn.net/?f=pH%20%3D%20-%20log%20%5Bx%5D%20%3D%20-%20log%20%5B%200.283%20%2A%2010%5E%7B-2%7D%5D%5C%5C%20%5C%5CpH%20%3D%202%20%2B%200.548%20%3D%202.54)
So the pH of the solution is 2.54.
hope it helps ..............
V ( NaOH ) = mL ?
M ( NaOH ) = 0.100 M
V ( HCl ) = 9.00 mL / 1000 => 0.009 L
M ( HCl ) = 0.0500 M
number of moles HCl:
n = M x V
n = 0.009 x 0.0500 => 0.00045 moles HCl
mole ratio:
<span>HCl + NaOH = NaCl + H2O
</span>
1 mole HCl ---------------- 1 mole NaOH
0.00045 moles HCl ----- ??
0.00045 x 1 / 1 => 0.00045 moles of NaOH
M = n / V
0.100 = 0.00045 / V
V = 0.00045 / 0.100
V = 0.0045 L
1 L ------------ 1000 mL
0.0045 L ----- ??
0.0045 x 1000 / 1 => 4.5 mL of NaOH
Answer:
for what I can see in the picture the volume is 155
Explanation: