Chemistry · Science General

States of Matter

2,682 Questions

States of matter questions explore physical changes, evaporation, phase transitions, and the properties of liquids and gases. Topics cover density, cryosurgery, heavy water, and electrolytes. This foundational chemistry topic frequently appears in general science sections of SSC and railway exams.

Phase change mechanismsEvaporation and temperature effectsProperties of liquidsPhysical versus chemical changesElectrolytes and heavy water

States of Matter Questions

Multiple choice fluid dynamics option b: engineering physics physics

With the increasing molecular mass of a liquid, the viscosity .

  1. decreases

  2. increases

  3. no effect

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

With the increasing molecular mass of a liquid, the viscosity increases.
The flow of molecules is inversely proportional to its mass. Hence, liquids with high molecular mass possess greater viscosity.

Multiple choice chemistry p- block elements-ii compounds of phosphorus - pcl3 phosphorus halides compounds of phosphorus compounds of phosphorus- pcl5

Choose the correct statement.

  1. White or yellow phosphorus is stored under water

  2. Ignition temperature of red phosphorus is low

  3. Black phosphorus is non crystalline in nature

  4. Phosphorus does not form hydrides
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Due to low ignition temperature of white phosphorus, it undergoes oxidation in presence of air which slowly raises its temperature and after a few moments it catches fire spontaneously. Due to this reason, it is stored under water. Ignition temperature ofred phosphorus is high Black phosphorus is crystalline in nature. Phosphorus forms a number of hydrides

Multiple choice chemistry p- block elements-ii compounds of phosphorus - pcl3 phosphorus halides compounds of phosphorus compounds of phosphorus- pcl5

Is ${PCl} _{3}$ soluble in water?

  1. Not Soluble

  2. May be

  3. Partially soluble

  4. Soluble
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
like dissolve like. It means polar molecules dissolves in polar molecules and non-polar molecules.Molecules dissolves in non polar molecules $Water$ and $PCl _3$ both are polar molecules because of their shape and electronegative difference between $H$ and $O$ in water and $P$ and $Cl$ in $PCl _3$. Hence $PCl _3$ is solube in water.
$PCl _3$ dissolve in water to form phosphorous acid.
$PCl _3$ $+$ $3H _2O$  $\longrightarrow $   $H _3PO _3$ $+$ $3HCl$
Multiple choice chemistry introduction to analytical chemistry interpreting a balanced chemical reaction percentage yield stoichiometric calculations
Statement (A):The constant temperature at which a solid change into liquid state by absorbing heat energy is called melting point.
Statement (B): The constant temperature at which a liquid changes into gaseous state by absorbing heat energy is called point.
Statement (C): The melting and boiling points of a pure substance is always a constant and is a good measure of finding the purity of the substance.

  1. All the statement are correct

  2. All the statement are incorrect

  3. A, B are correct and C is incorrect

  4. A, B are incorrect and C is correct
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

$A\rightarrow $ Its defination of melting point.

$B\rightarrow $ Its defination of boiling point. 
$C\rightarrow $ Pure substance have constant boiling and melting point. 
$\therefore $ All are true.

Multiple choice chemistry introduction to analytical chemistry interpreting a balanced chemical reaction percentage yield stoichiometric calculations

Which of the following is not the criterion of purity of a substance?

  1. Solubility

  2. Melting point

  3. Boiling point

  4. Density
Reveal answer Fill a bubble to check yourself
A,D Correct answer
Explanation

A pure substance shows a sharp melting point & boiling point. Hence melting point & boiling point determines the purity.

But density & solubility are not the criterion of purity of substance.

Multiple choice chemistry changes around us crystallisation process of separating components of a mixture physical changes

What is a chemical change?

  1. Change in size, shape

  2. Change from one substance to another new substance

  3. Change in temperature from lower to higher

  4. None of above
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

A chemical change is a process where one or more substances are converted into one or more new substances. Examples: Explosion of fireworks that produces heat, light, sound and unpleasant gases, breaking down of ozone in the ozone layer by the UV radiations.


Hence, the correct option is $B$

Multiple choice chemistry changes around us crystallisation process of separating components of a mixture physical changes
An example of chemical change is :

  1. water condensing on the outside of your cold beverage

  2. bending a wire

  3. slicing bread

  4. freezing water

  5. burning a candle
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

Burning of candle is a chemical change because the wax gets converted into carbon dioxide whereas the rest of the options represent the physical change.


Hence the correct option is E.

Multiple choice chemistry changes around us crystallisation process of separating components of a mixture physical changes

While forming crystals, it is important to :

  1. evaporate to dryness to get purest possible crystals

  2. attach gas syringes to collect fumes

  3. not evaporate water of crystallization

  4. use high flames
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Crystals contain water of crystallization hence during formation of crystals water of crystallization should not be evaporated.

Also, crystallization is the process of formation of crystals. Crystals is defined as the highly organized molecule into a well-known structure.