Our bone marrow continuously makes new red and white blood cells. The lymphatic system consists of the bone marrow, the spleen, the thymus (in young people), and lymph nodes.
First, we will get the average pH of the two given values:
average pH = (6.4+8) / (2) = 7.2
At this average pH, the concentration of the acid from the phenol red is equal to the concentration of the base.
pH = 7.2
[H+] = 10^(-7.2) = 6.3 * 10^-8
Phenol red has the general formula HA, this gives us:
HA <.......> H+ + A-
At pH = 7.2, [H+] = [A-]
<span>Ka = [H+][A-]/ [HA]
</span>Ka = [H+] = <span>6.3 x 10^-8</span>
Answer:

Explanation:
1. Calculate the work
w = - pΔV = -4.3 atm × (43 L - 20 L) = -4.3 × 23 L·atm = -98.9 L·atm
2. Convert litre-atmospheres to joules

The negative sign indicates that the work was done against the surroundings.
The reaction that should be followed is
Na2SO4 + C<span>a(NO3)2 --> CaSO4 + 2NaNO3</span>
first calculate the limiting reactant
mol Na2SO4 = 0.075 L (<span>1.54×10−2 mol / L) = 1.155x10-3 mol
mol Ca(NO3)2 = 0.075 L (</span><span>1.22×10−2 mol / L) = 9.15x10-4 mol
so the limiting reactant is the Ca(NO3)2
so all of the Ca2+ will be precipitated, percentage unprecipitated = 0.00 % </span>
Answer:The answer is C) The total mass of C and D only.