sorry but if you are looking for an answer I don't know one. :(
Answer:
a. blue, b. red, c. red, d. basic - blue
Explanation:
a.washing powder ( containing sodium carbonate ) basic -blue
b. orange juice ( containing citric acid )- acidic -red
c. lemonade ( containing H2CO₃ )-acidic - red
d. cleaner ( containg NH₃ )- basic - blue
2,8,3 because Aluminium has the Atomic Number 13
Neutrons actually don't carry an electrical charge, which is why they are called neutrons because they are "Neutral".
The answer for this issue is:
The chemical equation is: HBz + H2O <- - > H3O+ + Bz-
Ka = 6.4X10^-5 = [H3O+][Bz-]/[HBz]
Let x = [H3O+] = [Bz-], and [HBz] = 0.5 - x.
Accept that x is little contrasted with 0.5 M. At that point,
Ka = 6.4X10^-5 = x^2/0.5
x = [H3O+] = 5.6X10^-3 M
pH = 2.25
(x is without a doubt little contrasted with 0.5, so the presumption above was OK to make)