Burning fossil fuels leads to the formation of acid rain. Acid rain has collected in this lake. A helicopter is dropping calcium hydroxide into the lake.
Calcium hydroxide dissolves in water to form an alkaline solution.
(i) what effect does an alkali have on the pH of an acidic lake ?
(ii) When calcium hydroxide reacts with sulphuric acid in the lake a calcium salt is formed.
What is the name of this salt?
Calcium carbonate
Calcium nitrate
calcium chloride
calcium sulphate
2007-02-08 07:57:02 · 5 answers · asked by Anonymous in Education & Reference ➔ Homework Help
(i) Alkali increases the pH of an acidic lake, and could neutralise it (pH 7) if the correct amount of alkali was put in.
(ii) Ca(OH)2 + H2SO4 (aq) = CaS + 3(O2) + 2(H2)
Calcium Hydroxide + Sulphuric acid = Oxygen + Hydrogen + Calcium Sulphate
This is easy to do if you balance both sides of the equation.
Hope this helps!
:-)
2007-02-08 08:21:29 · answer #1 · answered by bazz2202 3 · 1⤊ 0⤋
Acids normally have a ph of 1 through 6 on a ph scale while Bases normally have a pH of 8 through 14. You might then ask, how about pH of 7? It is the neutral, meaning not acid or basic.
When acids and bases react, they form a salt and water. A good example would be the one you mentioned. Calcium hydroxide, which is a base, and Sulphuric acid, which is an acid. If you react them together, you get Calcium Sulphate, which is a salt, and Water.
Ca(OH)2 (aq) + H2SO4(aq) = CaS(s) + 3O2 (g) + 2H2(g)
This fulfils the goal of acid-base reaction. When it come to answer question
1) The effect of alkalic (base) to acidic lake, this will raise the pH and try to neutralize it because as I mentioned earlier, salt will be formed and Water, with a pH 7, will contribute to lowering of the pH in the acidic lake.
2) Salt formed is Calcuim Suphate, this can be seen from the equation above.
Hope this helps you.
2007-02-08 16:30:30 · answer #2 · answered by Bee 1 · 0⤊ 0⤋
Acids bring the pH down. Alkalis bring the pH up. With just the right amount, the pH will be neutral again (=7). If they put too much, the lake will become basic, and that's not good for it either.
calcium hydroxide=Ca(OH)2
Sulphuric acid = H2SO4
combined, it becomes CaSO4=calcium sulphate.
2007-02-08 16:04:03 · answer #3 · answered by petite_laeti 2 · 0⤊ 1⤋
acids lower ph, alkalis raise it
Sulfuric acid is H2SO4, Calcium Hydroxide is Ca(OH)2
It should produce calcium sulfate and water
2007-02-08 16:14:17 · answer #4 · answered by Grover 3 · 0⤊ 1⤋
1. reduces the ph of lake
2. calcium sulphate
2007-02-08 16:01:23 · answer #5 · answered by Marcella S 5 · 0⤊ 1⤋