Materials: Metals and non-metals Worksheet-4

Materials: Metals and non-metals Worksheet-4

31. The colour of Copper sulphate (CuSO₄.5H₂O) is _____.

A. Red                B. Blue               C. Green             D. Yellow

32. Which of the following is very reactive non metal?

A. Sodium                                      B. Potassium

C. Carbon                                       D. Phosphorous

33. ______ is used in wrapping soaps, cigarettes and confectionary.

A. Aluminium                               B. Silver

C. Nickeloy                                    D. Magnelium

34. Bronze is an alloy of _____.

A. Copper and Tin                       B. Copper and Zinc

C. Copper and Nickel                  D. Copper and Iron

35. When copper metal is exposed to moist air for long time it acquires a dull green coating. The green material is a mixture of ______.

A. Cu(OH)₂ and CuCO₃             B. Cu(OH)₂ and CuO

C. CuCO₃ and CuO                      D. CuO and Cu₂O

36. Which of the following metals will be replaced by zinc from its salt solution?

A. Aluminium sulphate              B. Copper sulphate

C. Sodium sulphate                     D. Magnesium sulphate

37. Metallic oxides are-

A. Acidic is nature                        B. Neutral

C. Basic in nature                         D. Either acidic or basic

38. Which non metal is used in water purification process?

A. Chlorine        B. Iodine            C. Oxygen           D. Sulphur

39. Iron is _____ reactive than Zinc.

A. less                 B. more

40. When iron is exposed to moist air for long time a reddish brown substance called rust is formed. What is chemical composition of rust?

A. Rust is basic iron oxide

B. Rust is a mixture of FeO and Fe₂(CO₃)₃

C. Rust is hydrated Ferric oxide.

D. Rust is a mixture of FeO, Fe₂(CO₃)₃Fe(OH)₃

41. Which of the following is  used in crackers?

A. metals                                        B. Semi metals

C. Non-metal                                 D. All of these

42. Hydrogen gas is produced when metals react with-

A. Acid                                            B. Base

C. Salt                                             D. Both acid & base

43. Which of the following can't be beaten into sheets?

A. Zinc                B. Iron                C. Aluminium   D. Sulphur

44. Moist air is the combination of-

A. H₂O+CO₂+O₂                          B. H₂O+CO+O₂

C. H₂O+CO₂+H₂                          D. H₂O+O₂+H₂

45. What happens when iron nails are immersed in copper sulphate solution?

A. The colour of the solution does not change

B. The colour of the solution change from blue to green

C. The colour of the solution change from green to blue

D. The solution becomes colourless

Answer:

31. B

32. D

33. A

Explanation: Thin foils of aluminium are used in wrapping soaps, cigarettes and confectionary.

34. A

Explanation: Bronze used for making coins, utensils, statues is an alloy of copper and tin.

(Cu-75-90%, Sn 25 -10%)

35. A

Explanation: The green material is a mixture of copper hydroxide (Cu(OH)₂) and copper carbonate

(CuCO₃).

36. B

Explanation: Zinc will replace copper from copper sulphate forming Zinc sulphate.

Zn + CuSO₄ → ZnSO₄ + Cu

The blue colour of copper sulphate disappears when zinc granules are added to copper sulphate solution. Powdery red mass of copper is deposited at the bottom of the vessel.

Aluminium, sodium and magnesium are more reactive than zinc so these metals will replace zinc from its salt solution.

37. C

Explanation: Aqueous solution of metallic oxides is alkaline in nature. It changes red litmus blue.

38. A

Explanation: Chlorine is used for purification of water.

39. A

Explanation: In the metal reactivity series iron is placed below zinc.

40. C

Explanation: Iron metal reacts with air and moisture forming hydrated iron oxide.

41. C

42. D

Explanation: Example:

2Al + 2NaOH + 2H₂O → 2NaAlO₂ + 3H₂

2Al + 6HCl → 2AlCl₃ + 3H₂

43. D

Explanation: Sulphur is a non metal hence it can’t be beaten into sheets.

44. A

45. B

Explanation: Iron replaces copper from copper sulphate forming iron sulphate. Thus the colour of the solution changes from blue to green. Reddish brown deposits of copper can be seen at the bottom of test tube.