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

What is the full form of ORS?

  1. Oral Resolute Solvent

  2. Oral Rejuvenating Solvent

  3. Oral Rehydration Solution

  4. Oral Replenishing Solution
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

ORS stands for Oral Rehydration Solution, a simple but life-saving mixture of clean water, salt (sodium chloride), and sugar (glucose). It is used to treat dehydration caused by diarrhea, cholera, and other gastrointestinal infections. The glucose enhances sodium absorption in the intestines through the SGLT1 transporter, helping the body retain water and electrolytes. The other options are not the standard medical term.

Multiple choice

In direct sunlight, water in a steel saucer evaporates faster than water in a glass tumbler. Why?

  1. Water in saucer is heated faster.

  2. Rate of evaporation depends on the surface area of the liquid.

  3. Steel enhances the rate of evaporation while glass is an inert material.

  4. Saucer allows all the water molecules to escape whereas a tumbler holds back some of the vapour from escaping.

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Evaporation occurs at the surface of a liquid. So larger the surface area, higher is the rate of evaporation. 

Multiple choice

In which of the following conditions will the rate of evaporation arrested to the maximum extent when water in a saucer is left exposed to direct sunlight for two days?

  1. When a pinch of salt is mixed in the water.

  2. When a pinch of sugar is mixed in the water.

  3. When two spoons of oil are added to the water.

  4. When water in the saucer is stirred with a spoon continuously for five to six minutes every hour.

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Evaporation happens faster when there is less exertion or shielding on the surface of the liquid. Oil forms a thin immiscible film on the water surface. Hence, rate of evaporation will be largely arrested. 

Multiple choice

Consider saucer A containing seawater, saucer B containing river water and saucer C containing processed drinking water poured from a packaged pouch. What will happen when all three of them are kept exposed to direct sunlight for two days provided that the amount of water in each of the saucers is the same?

  1. All three water samples will evaporate at the same time.

  2. Rate of evaporation will be the highest in drinking water followed by river water and least in the seawater.

  3. Rate of evaporation will be the highest in seawater followed by river water and least in the drinking water.

  4. Seawater and river water will evaporate, but the drinking water will remain as it is.

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Rate of evaporation decreases with increase in density of the evaporating liquid. Density of seawater > river water > drinking water Therefore, seawater evaporates at a lower rate. 

Multiple choice

Why dew drops are formed on the outer surface of a glass of chilled water?

  1. Molecules of water pass through the minute pores of the glass and deposit on its surface due to the low temperature.

  2. Cold water droplets spill over the surface of the glass at the time of filling.

  3. Glass reacts with chilled water and expels water molecules out of it.

  4. The vapour in air condenses on the cool surface of the glass resulting in fine dew drops.

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

When moist air comes in contact with the cooler surface, the vapourised form of water condenses. Thus dew drops are formed. 

Multiple choice

Why does water in a glass plate evaporate much earlier than the same amount of water in a glass tumbler when exposed to sunlight?

  1. <font face="Arial">The water in the <font size="2">pla<font size="2">te <font size="2">loses weight when exposed to direct sunlight, whereas the water in the tum<font size="2">bler does not lose weight. </font></font></font></font></font>

  2. <font face="Arial">The water in a plate gets exposed to more of warm air.</font>

  3. <font face="Arial">The water in the plate gets exposed to more of direct sun rays.</font>

  4. The plate gets heated in the sun and in turn heats up the water in it leading to evaporation.

  5. The water in the plate gains more dust and dirt particles that enhance the rate of evaporation.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Most thunderstorms are accompanied by downpour of irregular lumps of ice called hail. 

Multiple choice

Example of an element is

  1. air

  2. chlorine

  3. water

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

Chlorine is an element. Air is a mixture whereas water and sulphur dioxide are examples of compounds.