. Short Answer Type-l Questions:
1. What happens when the following metals react with dilute hydrochloric acid?
(a) magnesium (b) aluminium
2. Which of the following elements would form (i) acidic oxides and (ii) basic oxides?
(a) carbon
(b) magnesium (c) sulphur
(d) zinc (e) iron
3. What is meant by 'rusting of iron'?
4. What will be the change in the colour of copper sulphate solution when magnesium is added to it?
Write a balanced chemical equation for the same.
Answers
Answer:
1.(a) 2mgcl
(b) al2cl3
2.(a) c
(b) b
3.when iron come in contact of h2o, o2 for long time it get moisture and became rust.
4.cuso4+mn
Answer:
1) When magnesium and aluminium react with hydrochloric acid, they make their chlorides and hydrogen gas is liberated.
2)Carbon and sulphur would form acidic oxides
Magnesium, Sulphur and iron will form basic oxides
3) Rusting of iron refers to the formation of rust, a mixture of iron oxides, on the surface of iron objects or structures. This rust is formed from a redox reaction between oxygen and iron in an environment containing water (such as air containing high levels of moisture). The rusting of iron is characterized by the formation of a layer of a red, flaky substance that easily crumbles into a powder.
Chemical reaction :
4Fe + 3O2 + 6H2O → 4Fe(OH)3.
4) Aqueous copper sulfate solution is blue from the colour of the hydrated Cu++ cations and since the sulfate anion is colourless. The colour of the copper sulfate does not change during the reaction with magnesium metal.
CuSo4+Mg-------------->MgSO4+Cu
hope it helps u