Tag: chemistry

Questions Related to chemistry

Why iron is used widely in construction of buildings, bridges, railway lines etc?

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

  1. Iron is a good conductor of electricity

  2. Iron is ductile

  3. Iron have high tensile strength

  4. Iron is malleable

Show answer
Correct Option: C
Explanation:

Metals (except sodium, potassium) have very high tensile strength.
For example - iron can bear a lot of tensile strength. So, it is used in construction of buildings, bridges, railway lines etc.

Identity the element which can't conduct electricity:

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

  1. graphite

  2. iron

  3. phosphorus

  4. copper

Show answer
Correct Option: C
Explanation:

Phosphorus is a non-metal. It do not have free electrons for conduction. So, it is bad conductor of electricity.

The density of ice is $0.921\;g\ cm^{-3}$. Calculate the mass of a cubic block of ice which is $76\;mm$ on each side.

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

  1. $49 :g$

  2. $4\times 10^2\;g$

  3. $0.04 :g$

  4. $4\times 10^3\;g$

Show answer
Correct Option: B
Explanation:

Now, 1 $mm $ =   0.1 $cm$

$ \therefore $ 76$mm $ =   7.6 $cm$
Volume of cube $ =  $ $ (7.6)^3$ $ =  $ 438. 98 $ cm^3$
Now, mass $ =  $ density $ \times $ volume $ =  $ 0.921 $ \times $ 438.98 $ =  $ 404 $g$ $ =  $ $ 4.04 \times10^2 :g$

The mass of a piece of paper is $0.02\;g$ and the mass of a social substance and the piece of paper is $20.036\;g$. The volume of the solid substance is $2.16\;cm^3$. Calculate the density of the substance.

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

  1. $9.98$

  2. $7.36$

  3. $7.14$

  4. $9.268$

Show answer
Correct Option: D
Explanation:

Mass of piece of paper $=0.02\;g$


Mass of solid substance and piece of paper $=20.036\;g$

$\therefore$ Mass of solid substance $=20.036\;g-0.02\;g$

$\approx 20.02\;g$

Volume of solid $=2.16\;cm^3$

Density = $\dfrac{Mass}{Volume}=\dfrac{20.02}{2.16}=9.268 \ g/cm^3$

The mass of steel sphere having density 7850$\;kg :m^{-3}$ and radius 0.15$\;m$ is:

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

  1. 112$\;kg$.

  2. 290$\;kg$.

  3. 110.9$\;kg$.

  4. 300$\;kg$.

Show answer
Correct Option: C
Explanation:

Mass  of the sphere, $M = Density \times Volume$


Volume of the sphere is, $ V= \dfrac {4}{3} \pi r^3$


$ V=  \dfrac {4}{3} \pi (0.15)^3= 0.01412  \ m^{3} $

$M= 7850 \times 0.01412$

$= 110.9 \:kg$

Which of the following has lowest density?

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

  1. Oxygen

  2. Hydrogen

  3. Neon

  4. Carbon

Show answer
Correct Option: B
Explanation:

Hydrogen

Among all non-metals. Hydrogen has less density even its density is lesser than air.

Metals have:

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

  1. high density

  2. low density

  3. moderate density

  4. none of above

Show answer
Correct Option: A
Explanation:

Metals have a high density hence they feel heavy for their size whereas non-metals have a low density.

Density is:

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

  1. mass per time

  2. mass per weight

  3. mass per volume

  4. mass per atomic weight

Show answer
Correct Option: C
Explanation:

The density, or more precisely, the volumetric mass density, of a substance is its mass per unit volume. The symbol most often used for density is $\rho$.

Which of the following statement is correct?

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

  1. All metals are ductile.

  2. All non-metals are ductile.

  3. Generally, metals are ductile.

  4. Some non-metals are ductile.

Show answer
Correct Option: C
Explanation:

Metals are generally malleable — that is, they can be hammered or pressed permanently out of shape without breaking or cracking — as well as fusible (able to be fused or melted) and ductile (able to be drawn out into a thin wire). 


Typically they are malleable and ductile, deforming under stress without cleaving. There are metals which are not ductile. 
For example sodium and mercury.

The high density of most of the metals is due to the_________.

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

  1. loosely packed crystal lattice of the metallic structure

  2. weak metallic bonding

  3. tightly packed crystal lattice of the metallic structure

  4. strong ionic bonding

Show answer
Correct Option: C
Explanation:

The high density of most metals is due to the tightly packed crystal lattice of the metallic structure.