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Multiple choice chemistry metals physical properties of metals and non-metals some physical properties of metals general characteristics and uses of metals

Non-metals are non-malleable due to absence of:

  1. covalent bonding

  2. ionic bonding

  3. metallic bonding

  4. co-ordinate bonding
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Malleability in metals occurs because of the metallic bonds that keep the atoms in place. Metallic bonds, characterized by a 'sea' of electrons that easily move from atom to another, allow the metal atoms to slide past each other if a force is applied. Non-metals are hard and brittle due to the absence of these electron pools of metallic bonds. 


Hence, the correct option is $\text{C}$

Multiple choice chemistry metals physical properties of metals and non-metals some physical properties of metals general characteristics and uses of metals

Carbon foils can not be made because of the reason that:

  1. no-metallic bonding to allow one electron slip over another

  2. do not deform on hammering

  3. both of these

  4. none of these
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Carbon is a non-malleable element. Malleability is a physical property of matter, usually metals to bend or be hammered into other shapes without breaking. Carbon do not deform due to absence of the  metallic bonds which is required to be malleable as it keep the atoms in place and allows one electron slip over another. 

Multiple choice chemistry metals physical properties of metals and non-metals some physical properties of metals general characteristics and uses of metals

Potassium on exposure to air gives:

  1. Potassium peroxide

  2. Potassium superoxide

  3. Potassium dioxide

  4. Potassium oxide
Reveal answer Fill a bubble to check yourself
A,B,D Correct answer
Explanation

Potassium is an extremely active metal that reacts violently with oxygen in air. Potassium oxidizes faster than most metals and forms oxides with oxygen-oxygen bonds. Three species are formed during the reaction: potassium oxide, potassium peroxide, and potassium superoxide.

$8K + 4O _2 \rightarrow 2K _2O + 2KO _2 + K _2O _2$

Multiple choice chemistry metals physical properties of metals and non-metals some physical properties of metals general characteristics and uses of metals

Four metals $P$, $Q$, $R$ and $S$ react with water as given below:
I. $P$ reacts with cold water
II. $Q$ reacts with hot water
III. $R$ reacts with steam
IV. Red hot $S$ reacts with steam.
Then, highly reactive metal is:

  1. $P$
  2. $Q$
  3. $R$
  4. $S$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The highly reactive metal is $P$ as it reacts with cold water. This is because, the reaction with cold water requires lowest energy of activation.

Multiple choice chemistry metals physical properties of metals and non-metals some physical properties of metals general characteristics and uses of metals

Select the object from the following which can shine (have lusture) _____________

  1. glass bowl and wooden bowls

  2. towel and toys

  3. shirts and scarfs

  4. ornaments and brass utensils
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

1) ornaments and brass utensils both are made up of metals.

2) Metals are lustrous because of the free electrons they have.

3) The free electrons can move freely in the metal causing any light incident on them to get reflected back.

4) This reflection is specular reflection rather than diffused and thus the metal surface appears shiny or lustrous.

Multiple choice chemistry metals physical properties of metals and non-metals some physical properties of metals general characteristics and uses of metals

Metallic radii of some transition elements are given below. Which of these elements will have the highest density?
Element                    $Fe$     $CO$       $Ni$     $Cu$ 
Metallic radii/pm     126     125     125    128

  1. same

  2. $Ni$
  3. $Co$
  4. $Cu$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Density is mass divided by volume. For transition elements in the same period, as atomic number increases, the atomic radius generally decreases or stays similar, while the atomic mass increases significantly. Copper (Cu) has the highest atomic mass among the listed elements (Fe, Co, Ni, Cu), leading to the highest density.

Multiple choice chemistry metals physical properties of metals and non-metals some physical properties of metals general characteristics and uses of metals

Which one of the following four metals would be displaced from the solution of its salt by other three metals?

  1. Mg

  2. Ag

  3. Zn

  4. Cu
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Ag metal would be displaced from the solution of its salt by Mg, Zn or Cu metals.

Among the given metals, the standard reduction potential for the half reaction $\displaystyle Ag^+ + e^- \rightarrow Ag$ is maximum.

Hence, among the given metals (ions),  $\displaystyle Ag^+ $ ion has maximum strength as oxidising agent. Hence, $\displaystyle Ag^+$ ion gains an electron and other metals loses electron.

Multiple choice chemistry metals physical properties of metals and non-metals some physical properties of metals general characteristics and uses of metals

Read the following statements and answer as true or false.
The presence of carbon in pig iron makes it brittle.

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

 Pig iron has a very high carbon content, typically 3.8–4.7%, along with silica and other constituents of dross, which makes it very brittle, and not useful directly as a material except for limited applications.