Tag: chemistry

Quizzes (490) Questions (9892)

Questions Related to chemistry

Multiple choice chemistry materials liquid crystals liquid state the liquid state

Atmospheric pressures recorded in different cities are as follows:

Cities Shimla Bangalore Delhi Mumbai
$p$ in $N/m^{2}$ $1.01\times 10^{5}$ $1.2\times 10^{5}$ $1.02\times 10^{5}$ $1.21\times 10^{5}$


Consider the above data and mark the place at which liquid will boil first.

  1. Shimla

  2. Bangalore

  3. Delhi

  4. Mumbai
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The boiling point of a liquid is the temperature at which vapour pressure becomes equal to the atmospheric pressure. Lower the atmospheric pressure, lower is the boiling point.

Since the atmospheric pressure of the Shimla is minimum, thus the boiling point of the liquid will be lowest at Shimla.

Multiple choice chemistry materials liquid crystals liquid state the liquid state

Metallic liquids contain:

  1. metal atoms

  2. ions and mobile electrons

  3. aggregates of metal atom

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

When metals are in liquids, they dissociate into ions and give away electrons. So, metallic liquids contain ions and mobile electrons.

Ex: $Na _{(s)}\longrightarrow Na^+ _{(ag)}+e^-$
Ex: $Mg _{(s)}\longrightarrow Mg^{+2} _{(ag)}+2e^-$

Multiple choice chemistry materials liquid crystals liquid state the liquid state

When a solid crystal is melted, it should become a liquid. Liquid crystals are an intermediate stage between a liquid and a crystal. Which of the following is a liquid crystal of a non-living system?

  1. Cholesteryl bromide

  2. Axons of nerve

  3. Striated muscle fibre

  4. Cilia
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Axons of nerve, striated muscle fibre, cilia all belong to bio-logical living systems.

Cholesteryl bromide $(C _{27}H _{45}Br)$ is a liquid crystal of a non-living system.

Multiple choice chemistry materials around us and different types of houses materials around us matter and its states different states of matter

Liquids are known to have density lower than solid because:

  1. the number of particles is less and the inter-molecular space is minimum

  2. the number of particles is less and the inter-molecular space is more.

  3. the number of particles is least and the inter-molecular space is more.

  4. the number of particles is less and the inter-molecular space is maximum.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Liquids have lower density than solids because the particles in liquids are less tightly packed, resulting in larger intermolecular spaces compared to the rigid, closely packed structure of solids.

Multiple choice chemistry materials around us and different types of houses materials around us matter and its states different states of matter

The combustion of candles, containing paraffin wax, to carbon dioxide and water vapor is:

  1. sublimation as well as chemical reaction with oxygen

  2. only sublimation

  3. not sublimation but a chemical reaction with oxygen

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

The term sublimation refers to a physical change of state and is not used to describe transformation of a solid to a gas in a chemical reaction. The combustion of candles, containing paraffin wax, to carbon dioxide and water vapor is not sublimation but a chemical reaction with oxygen.

Multiple choice chemistry materials around us and different types of houses materials around us matter and its states different states of matter

Which of the following can be a definition for solids? 

  1. A state of matter that has a definite volume but not a definite shape.

  2. A state of matter that has both a fixed volume and shape.

  3. A state of matter that does not have a definite volume or shape.

  4. A state of matter that conducts electricity well.

  5. A state of matter similar to gas that has free electrons.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The molecules of a solid are fixed within the solid, and they just vibrate about their mean position. 


Due to this constant positioning, solids have a fixed volume and shape.

Hence the correct option is B.