Answer:
B.Add acid to water,not water to acid
Explanation:
they should not be mixed
The answer is Solid.
This is on account of the substances that develop a solid are packed in a settled, firmly pressed geometric plan.
The pressure at the bottom : 19600 N/m²
<h3>Further explanation</h3>
Given
A ground water tank has its height 2m
Required
The pressure at its bottom
Solution
Hydrostatic pressure is the pressure caused by the weight of a liquid.
The weight of a liquid is affected by the force of gravity.
The hydrostatic pressure of a liquid can be formulated:

Ph = hydrostatic pressure (N / m², Pa)
ρ = density of liquid (kg / m³)
g = acceleration due to gravity (m / s²)
h = height / depth of liquid surface (m)
ρ = density of water (kg / m³) = 1000
g = acceleration due to gravity = 9.8 m/ sec²
The pressure

Answer:
Ka = 
Explanation:
Initial concentration of weak acid =
pH = 6.87
![pH = -log[H^+]](https://tex.z-dn.net/?f=pH%20%3D%20-log%5BH%5E%2B%5D)
![[H^+]=10^{-pH}](https://tex.z-dn.net/?f=%5BH%5E%2B%5D%3D10%5E%7B-pH%7D)
![[H^+]=10^{-6.87}=1.35 \times 10^{-7}\ M](https://tex.z-dn.net/?f=%5BH%5E%2B%5D%3D10%5E%7B-6.87%7D%3D1.35%20%5Ctimes%2010%5E%7B-7%7D%5C%20M)
HA dissociated as:

(0.00045 - x) x x
[HA] at equilibrium = (0.00045 - x) M
x = 
![Ka = \frac{[H^+][A^{-}]}{[HA]}](https://tex.z-dn.net/?f=Ka%20%3D%20%5Cfrac%7B%5BH%5E%2B%5D%5BA%5E%7B-%7D%5D%7D%7B%5BHA%5D%7D)

0.000000135 <<< 0.00045
