Gas released during which of the following reactions produces a pop sound (when the gas is burned
in air)?
1. Pouring hydrochloric acid on iron granules
2. Calcium carbonate and sulfuric acid
3. Aluminium with sulfuric acid
4. Potassium hydroxide and zinc
5. Sodium hydroxide and hydrochloric acid
(A) 1.3.5
(B) 2.4.5
(C) 1,3,4
(D) 1,2,4
Answers
Answer:
1. What happen when dilute hydrochloric acid is added to iron filling? when dilute HCl is added to Fe then Ferrous chloride ( FeCl2) and hydrogen gas (H2) will be formed.
2. Sulphuric acid gives calcium sulphate, carbon dioxide gas and water when it reacts with calcium carbonate.
CaCO
3
+H
2
SO
4
→CaSO
4
+CO
2
+H
2 O.
3. Aluminium reacts with sulfuric acid (h2so4) to produce aluminium sulfate al2(so4)3 and hydrogen (h2).
4. Zinc is an active metal and it reacts with potassium hydroxide to form potassium zincte (K
2
ZnO
2 ).
5. A salt is a neutral ionic compound. Let's see how a neutralization reaction produces both water and a salt, using as an example the reaction between solutions of hydrochloric acid and sodium hydroxide. The overall equation for this reaction is: NaOH + HCl → H2O and NaCl.