Q1.
Which of the following is a physical property of metals?
(A) Reaction with acids
(B) Formation of metal oxides
(C) Metallic lustre
(D) Displacement reactions
Q2.
The property of metals by which they can be beaten into thin sheets is called:
(A) Ductility
(B) Malleability
(C) Sonority
(D) Conductivity
Q3.
Which metal is the best conductor of electricity?
(A) Copper
(B) Silver
(C) Gold
(D) Aluminium
Q4.
Non-metals are generally:
(A) Good conductors of heat and electricity
(B) Malleable and ductile
(C) Brittle and dull
(D) Sonorous
Q5.
Which of the following is an exception to the general properties of non-metals?
(A) Carbon (diamond) - hardest natural substance
(B) Graphite - conducts electricity
(C) Iodine - has metallic lustre
(D) All of the above
Q6.
When metals react with oxygen, they form:
(A) Metal hydroxides
(B) Metal oxides
(C) Metal carbonates
(D) Metal sulphates
Q7.
The reaction: Zn + CuSO4 → ZnSO4 + Cu is an example of:
(A) Combination reaction
(B) Decomposition reaction
(C) Displacement reaction
(D) Double displacement reaction
Q8.
Which gas is produced when metals react with acids?
(A) Oxygen
(B) Carbon dioxide
(C) Hydrogen
(D) Nitrogen
Q9.
In the reactivity series, which metal is placed at the top?
(A) Iron
(B) Copper
(C) Potassium
(D) Gold
Q10.
Rusting of iron is an example of:
(A) Corrosion
(B) Displacement
(C) Reduction
(D) Sublimation
Q11.
Which method is used to prevent rusting of iron?
(A) Galvanization
(B) Painting
(C) Oiling
(D) All of the above
Q12.
An alloy is:
(A) A pure metal
(B) A mixture of two or more metals
(C) A compound of metals
(D) A non-metal
Q13.
Steel is an alloy of:
(A) Iron and carbon
(B) Copper and zinc
(C) Copper and tin
(D) Iron and nickel
Q14.
Which of the following metals does not react with cold water?
(A) Sodium
(B) Potassium
(C) Magnesium
(D) Calcium
Q15.
The most malleable metal is:
(A) Silver
(B) Gold
(C) Copper
(D) Aluminium
Q16.
Which of the following pairs will show displacement reaction?
(A) NaCl + Cu
(B) MgSO4 + Al
(C) CuSO4 + Fe
(D) FeSO4 + Cu
Q17.
Brass is an alloy of:
(A) Copper and tin
(B) Copper and zinc
(C) Iron and carbon
(D) Iron and chromium
Q18.
Which metal is used for galvanizing iron?
(A) Copper
(B) Zinc
(C) Tin
(D) Lead
Q19.
When sodium reacts with water, it produces:
(A) NaOH + H2
(B) Na2O + H2
(C) NaH + O2
(D) Na2SO4 + H2
Q20.
Which property allows metals to be drawn into wires?
(A) Malleability
(B) Ductility
(C) Conductivity
(D) Sonority
Q21.
The reddish-brown coating on iron is called:
(A) Corrosion
(B) Rust
(C) Patina
(D) Tarnish
Q22.
Which non-metal is essential for combustion?
(A) Nitrogen
(B) Carbon
(C) Oxygen
(D) Hydrogen
Q23.
Stainless steel contains:
(A) Iron and carbon
(B) Iron, chromium and nickel
(C) Copper and zinc
(D) Iron and aluminium
Q24.
Which metal is stored in kerosene?
(A) Magnesium
(B) Sodium
(C) Iron
(D) Copper
Q25.
The chemical formula of rust is:
(A) FeO
(B) Fe2O3
(C) Fe2O3.xH2O
(D) Fe3O4
Q1.
Metallic lustre is a physical property. Chemical properties include reactions with acids, oxygen, water. Physical properties are observable without changing chemical composition.
Q2.
Malleability is the property of metals to be beaten into thin sheets. Ductility is drawing into wires. Examples: aluminum foils (malleability), copper wires (ductility).
Q3.
Silver is the best conductor of electricity among all metals, followed by copper, gold, and aluminum. Used in high-quality electrical contacts and circuits.
Q4.
Non-metals are generally brittle (break easily), dull (no lustre), poor conductors of heat and electricity, and non-sonorous (don't produce ringing sound).
Q5.
All are exceptions: Diamond (carbon) is hardest, graphite conducts electricity, iodine has metallic lustre. These show non-metals can have some metallic properties.
Q6.
Metal + Oxygen → Metal oxide. Examples: 4Na + O₂ → 2Na₂O, 2Mg + O₂ → 2MgO. This is oxidation reaction.
Q7.
Displacement reaction: More reactive metal displaces less reactive metal from its salt solution. Zinc is more reactive than copper, hence displaces it.
Q8.
Metal + Acid → Salt + Hydrogen gas. Example: Zn + 2HCl → ZnCl₂ + H₂. Hydrogen gas can be tested with burning splinter (pop sound).
Q9.
Reactivity series: K > Na > Ca > Mg > Al > Zn > Fe > Pb > H > Cu > Hg > Ag > Au. Potassium is most reactive.
Q10.
Rusting is slow destruction of iron by oxygen and moisture, forming hydrated iron oxide (rust). It's a type of corrosion specific to iron and steel.
Q11.
All methods prevent rusting: Galvanization (zinc coating), painting (prevents air contact), oiling (moisture barrier). Each method blocks oxygen/moisture contact with iron.
Q12.
Alloy is homogeneous mixture of two or more metals, or metal with non-metal. Examples: Steel (Fe + C), Brass (Cu + Zn), Bronze (Cu + Sn).
Q13.
Steel is iron-carbon alloy with 0.1-1.5% carbon. Carbon makes steel harder and stronger than pure iron. Used in construction and machinery.
Q14.
Magnesium reacts very slowly with cold water. Sodium and potassium react vigorously, calcium reacts moderately. Mg needs hot water for significant reaction.
Q15.
Gold is most malleable metal. 1 gram of gold can be beaten into a sheet of 1 square meter area. Used in jewelry and decorative work.
Q16.
Fe + CuSO₄ → FeSO₄ + Cu. Iron is more reactive than copper (reactivity series), so displaces copper from its salt solution. Blue color changes to green.
Q17.
Brass = Copper + Zinc alloy. Used in musical instruments, decorative items, and electrical fittings due to its golden appearance and corrosion resistance.
Q18.
Zinc is used for galvanizing iron. Zinc is more reactive than iron, forms protective oxide layer preventing rusting. Sacrificial protection method.
Q19.
2Na + 2H₂O → 2NaOH + H₂. Sodium reacts vigorously with water producing sodium hydroxide and hydrogen gas. Reaction is highly exothermic.
Q20.
Ductility allows metals to be drawn into wires. Examples: copper wires, gold wires in electronics. Malleability is for beating into sheets.
Q21.
Rust is reddish-brown coating on iron formed by reaction with oxygen and moisture. Chemical formula: Fe₂O₃.xH₂O (hydrated iron oxide).
Q22.
Oxygen is essential for combustion (burning). It supports combustion and is required for fire. Combustion stops in absence of oxygen.
Q23.
Stainless steel contains iron, chromium (12-18%), and nickel (8-10%). Chromium prevents rusting by forming protective oxide layer. Used in cutlery, kitchen utensils.
Q24.
Sodium is stored in kerosene to prevent contact with air and moisture. It's highly reactive and catches fire in air. Kerosene is unreactive liquid.
Q25.
Rust formula is Fe₂O₃.xH₂O (hydrated ferric oxide). 'x' varies with moisture content. Rust is porous and doesn't protect underlying iron.