Answer:
(c) only Ca2+(aq) and Hg2+(aq)
Explanation:
- In the first step, hydrochloric acid (HCl) is added to the solution. In this case the equilibrium that could take place is:
Ag⁺(aq) + Cl⁻(aq) ↔ AgCl(s)
But no precipitate was formed, so Ag⁺(aq) is absent.
- By adding H₂SO₄(aq) the next equilibrium that could take place is:
Ca⁺²(aq) + SO₄⁻²(aq) ↔ CaSO₄(s)
A white precipitate was formed, so Ca⁺² is present in the solution.
- The following could take place after adding H₂S(aq):
Hg²⁺(aq) + S⁻² ↔ HgS(s)
A black precipitate formed, so Hg⁺² is present as well.
Atomic mass Cu = 63.546 a.m.u
63.546 g ---------------- 6.02x10²³ atoms
22 g --------------------- ??
22 x (6.02x10²³ ) / 63.546 => 2.08x10²³ atoms
hope this helps!
Answer: The pH of a 4.4 M solution of boric acid is 4.3
Explanation:
at t=0 cM 0 0
at eqm
So dissociation constant will be:
Give c= 4.4 M and
= ?
Putting in the values we get:
Also
Thus pH of a 4.4 M
solution is 4.3
it is either "aweak acid or a lousy (or very weak) acid"