Grade 10 : Science - 3. Metals/Non-Metals (Set 4) | Concept of Maths

Question 1

Study the following displacement reaction table where four metals P, Q, R, and S are tested with different salt solutions:

Accepted Answer

A) Q > P > R > S

Answer

B) P > Q > R > S

Answer

C) Q > P > S > R

Answer

D) S > R > P > Q

Question 2

A student sets up an experiment to study the reaction of metals with dilute acids as represented below:

Accepted Answer

B) M = \Copper  (Cu)

Answer

A) M = \Zinc  (Zn)

Answer

C) M = \Magnesium  (Mg)

Answer

D) M = \Iron  (Fe)

Question 3

Consider the electron-dot transfer schema representing the synthesis of Magnesium Chloride ($MgCl_2$):

Accepted Answer

C) It consists of $Mg^{2+}$ cations and $Cl^-$ anions held together by strong electrostatic forces of attraction, forming an ionic compound with a high melting point.

Answer

A) It consists of shared pairs of electrons between Mg and Cl, forming a covalent compound with low boiling points.

Answer

B) It is a coordinate compound where both bonding electrons are donated solely by the Magnesium atom.

Answer

D) It is an alloy with metallic bonding and high electrical insulating capabilities in its molten state.

Question 4

An industrial anodizing process is represented below:

Accepted Answer

A) Oxygen gas is liberated at the anode and reacts with Aluminium to form a thick protective oxide layer ($Al_2O_3$).

Answer

B) Hydrogen gas is liberated at the anode, reducing the aluminium surface to its purest form.

Answer

C) Sulphur dioxide is deposited as a salt onto the aluminium surface.

Answer

D) Aluminium is dissolved completely, leaving behind pure carbon deposits.

Question 5

The diagram below illustrates the setup for the electrolytic refining of copper:

Accepted Answer

D) $Cu^{2+}(aq) + 2e^- \rightarrow Cu(s)$

Answer

A) $Cu(s) \rightarrow Cu^{2+}(aq) + 2e^-$

Answer

B) $2H^+(aq) + 2e^- \rightarrow H_2(g)$

Answer

C) $SO_4^{2-}(aq) \rightarrow SO_2(g) + O_2(g) + 2e^-$

Question 6

Study the flowchart below showing the extraction of zinc from its carbonate ore:

Accepted Answer

B) Calcination; $ZnCO_3(s) \xrightarrow{\Delta} ZnO(s) + CO_2(g)$

Answer

A) Roasting; $2ZnS(s) + 3O_2(g) \xrightarrow{\Delta} 2ZnO(s) + 2SO_2(g)$

Answer

C) Reduction; ZnO(s) + C(s) \xrightarrow{\Delta} Zn(g) + CO(g)

Answer

D) Smelting; $ZnCO_3(s) + C(s) \rightarrow Zn(s) + 2CO_2(g)$

Question 7

Consider the experimental conditions set up in three test tubes containing iron nails:

Accepted Answer

C) Both air (oxygen) and water are essential for rusting; the oil layer in Tube 2 prevents air from dissolving in the water.

Answer

A) Only water is required for rusting; oxygen is completely unnecessary.

Answer

B) Only dry air is required for rusting; water actually prevents iron from rusting.

Answer

D) The presence of dissolved minerals in tap water is the sole cause of rusting.

Question 8

A comparative bar chart displays physical properties of pure Copper (Cu) and its alloy Brass:

Accepted Answer

A) Alloying decreases both the electrical conductivity and the melting point compared to its constituent pure metals.

Answer

B) Alloying increases both the electrical conductivity and the melting point.

Answer

C) Alloying increases electrical conductivity but decreases the melting point.

Answer

D) Alloying has absolutely no effect on electrical conductivity.

Question 9

The thermite process used for joining cracked railway tracks is represented schematically below:

Accepted Answer

B) $Fe_2O_3(s) + 2Al(s) \rightarrow 2Fe(l) + Al_2O_3(s) + \Heat$

Answer

A) $2Fe(s) + Al_2O_3(s) \rightarrow Fe_2O_3(s) + 2Al(l) + \Heat$

Answer

C) $3Fe_3O_4(s) + 8Al(s) \rightarrow 9Fe(s) + 4Al_2O_3(s) + \Heat$

Answer

D) $Fe_2O_3(s) + 3C(s) \rightarrow 2Fe(l) + 3CO(g) + \Heat$

Question 10

An oxide pH indicator experiment yields the following color results when dissolved in water:

Accepted Answer

D) Metallic oxides ($Na_2O, MgO$) are basic in nature (pH > 7), while non-metallic oxides ($SO_2, P_2O_5$) are acidic (pH < 7).

Answer

A) Metallic oxides ($Na_2O, MgO$) are acidic in nature, while non-metallic oxides ($SO_2, P_2O_5$) are basic.

Answer

B) Both metallic and non-metallic oxides are amphoteric and show neutral pH values.

Answer

C) Metallic oxides are neutral, whereas non-metallic oxides are highly basic.