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Class 6Science & Technology2026-27 Syllabus

Chapter 5 Substances in the Surroundings – Their States and Properties Solutions

Complete Maharashtra State Board Balbharati & Yuvakbharati textbook solutions for Chapter 5 Substances in the Surroundings – Their States and Properties. Step-by-step solved exercises, numerical problems, and digest answers.

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Maharashtra State Board Class 6 Science Solutions Chapter 5 Substances in the Surroundings – Their States and Properties

Class 6 Science Chapter 5 Substances in the Surroundings – Their States and Properties Textbook Questions and Answers

1. In the paragraph below write ‘solid’, ‘liquid’ or ‘gas’ in each of the blank (brackets) depending on the substance referred to just before.

Question a.
On a bright sunny day, Riya and Gargi are playing with a ball (…..) in the park. Gargi feels thirsty. So, Riya brings tender coconut water (…..) for her. At the same time, a strong breeze (…..) starts blowing and it also begins to rain (…..). They run back into the house (…..), change their clothes (…..) and then their mother gives them a cup (…..) of hot milk (…..) to drink.
Answer:
solid, liquid, gas, liquid, solid, solid, solid, liquid.

2. Discuss.

Question a.
Riya pours some water from her bottle into another bottle. Does it change the shape of the water?
Answer:
Yes, the shape of water changes as water is in liquid state. Liquids do not have a shape of its own. They take the shape of the container.

Question b.
Halima picks up a small stone from the ground and puts it in the water in a dish. Does the shape of the stone change?
Answer:
No, the shape of the stone does not change. Stone is a solid, hence retains its shape.

3. Write the properties of these substances.
(water, glass, chalk, iron ball, sugar, salt, flour, coal, soil, pen, ink, soap)

Question a.
Write the properties of these substances.
(water, glass, chalk, iron ball, sugar, salt, flour, coal, soil, pen, ink, soap)
Answer:
Properties of substances:

Substance

State

Properties

1. Water

Liquid

Fluidity, density, solubility, transparency, thermal conductivity.

2. Glass

Solid

Brittleness, hardness, density, transparency.

3. Chalk

Solid

Brittleness, density.

4. Iron ball

Solid

Hardness, density, malleability, ductility, electrical ductility, conductivity, thermal conductivity, luster, sonority.

5. Sugar

Solid

Brittleness, density, solubility.

6. Salt

Solid

Brittleness, density, solubility.

7. Flour

Solid

Density, solubility.

8. Coal

Solid

Brittleness, density, thermal conductivity.

9. Soil

Solid

Brittleness, density.

10. Pen

Solid

Hardness, density.

11. Ink

Liquid

Fluidity, density, solubility.

12. Soap

Solid

Brittleness, hardness, density, solubility.

4. What is sublimation? Write the names of everyday substances that sublimate.

Question a.
What is sublimation? Write the names of everyday substances that sublimate.
Answer:

5. What is made from? Why?
a. A sickle to cut sugarcane.
b. The sheets used for roofing.
c. A screwdriver
d. A pair of tongs.
e. Electric cables.
f. Ornaments.
g. Pots and pans.

Question a.
A sickle to cut sugarcane.
Answer:
A sickle is made of iron. An iron sickle is hard and malleable. When sharpened it will be able to cut the hard sugarcane.

Question b.
The sheets used for roofing:
Answer:

Question c.
A screwdriver:
Answer:

Question d.
A pair of tongs:
Answer:

Question e.
Electric cables:
Answer:

Question f.
Ornaments:
Answer:

Question g.
Pots and pans: Answer:

6. What will happen if ….? And why?

Question a.
Nails are made of plastic
Answer:
If nails are made of plastic, they will not be able to pierce through other substances on being pushed or forced by a hammer. Plastic lacks the property of hardness.

Question b.
A bell is made of wood.
Answer:

Question c.
Rubber is not fitted on a pair of tongs.
Answer:

Question d.
A knife is made of wood.
Answer:
Wood does not have the property of malleability. Therefore, the edge of wooden knife will be blunt. Hence, we will not be able to cut anything with it.

Question e.
An axe is made of rubber.
Answer:

7. Who am I?

Question a.
I’m found in a thermometer, I measure your temperature.
Answer:
Mercury

Question b.
I make things hot or cold.
Answer:
Heat

Question c.
I have no shape whatsoever!
Answer:
Liquid, gases

Question d.
I dissolve in water, but not in kerosene.
Answer:
Salt

8. Why does this happen?

Question a.
Coconut oil thickens in winter.
Answer:
Coconut oil is in liquid state. In winter the surrounding temperature / atmospheric temperature starts decreasing. Coconut oil starts cooling or losing heat, it changes to solid state.
Thus coconut oil thickens in winter.

Question b.
Kerosene left open in a dish disappears.
Answer:
When kerosene is left open in a dish, it is exposed to surrounding temperature. As the temperature is more, kerosene starts continuously evaporating and finally disappears.

Question c.
The fragrance of incense sticks lighted in one corner of a room spreads to the other corner.
Answer:
The fragrance of incense sticks is given out in the form of scented vapours. As vapours are in gaseous state, the gas molecules spread out in the room. The molecules of gas move very fast and there are no forces to stop them from going apart. Therefore the fragrance of incense sticks lighted in one corner of room spreads to the other corner.

Question d.
What you see in the picture.

Answer:
The mass of plastic ball is less than an apple. This difference is because of their densities. Since an apple has greater density, it will sink to the bottom on other hand the plastic ball has lesser density, it will float over water surface.

Activity:

Question 1 Maharashtra Board Solution
Find out how the big statues of wax are made.

Question 2 Maharashtra Board Solution
Visit a jeweller’s shop and find out how ornaments are made.

Class 6 Science Chapter5 Substances in the Surroundings – Their States and PropertiesImportant Questions and

Solution & Step-by-Step Answer:
s

Fill in the blanks:

Question 1 Maharashtra Board Solution
The state of a substance changes if it is …………… or …………….
Solution & Step-by-Step Answer:
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Solution & Step-by-Step Answer:
heated, cooled
Question 2 Maharashtra Board Solution
Every substance in our surroundings is found in either the ……………, …………… or gaseous state.
Solution & Step-by-Step Answer:
solid, liquid
Question 3 Maharashtra Board Solution
On …………… heat, the substance changes from solid to liquid and liquid to gas.
Solution & Step-by-Step Answer:
gaining
Question 4 Maharashtra Board Solution
When the substance cools, or …………… heat, it changes from gaseous to liquid and liquid to solid state.
Solution & Step-by-Step Answer:
loses
Question 5 Maharashtra Board Solution
A …………… amount of heat must be gained or lost before the state of a substance can change.
Solution & Step-by-Step Answer:
specific
Question 6 Maharashtra Board Solution
When a substance gets heat, it becomes …………… and then …………….
Solution & Step-by-Step Answer:
warm, hot
Question 7 Maharashtra Board Solution
If the substance is very hot, we could get …………….
Solution & Step-by-Step Answer:
scalded
Question 8 Maharashtra Board Solution
A thermometer is used to measure …………….
Solution & Step-by-Step Answer:
temperature
Question 9 Maharashtra Board Solution
…………… is the unit of measuring temperature.
Solution & Step-by-Step Answer:
Degree Celsius (°C)
Question 10 Maharashtra Board Solution
Nowadays, …………… thermometers are frequently used.
Solution & Step-by-Step Answer:
digital
Question 11 Maharashtra Board Solution
Solids have a shape of its …………….
Solution & Step-by-Step Answer:
own
Question 12 Maharashtra Board Solution
Solids have a …………… volume.
Solution & Step-by-Step Answer:
definite
Question 13 Maharashtra Board Solution
Liquids take the shape of the …………….
Solution & Step-by-Step Answer:
container
Question 14 Maharashtra Board Solution
Liquids have a …………… volume.
Solution & Step-by-Step Answer:
specific
Question 15 Maharashtra Board Solution
Air occupies all the available …………….
Solution & Step-by-Step Answer:
space
Question 16 Maharashtra Board Solution
Evaporation occurs from the …………… of the water.
Solution & Step-by-Step Answer:
surface
Question 17 Maharashtra Board Solution
At sea-level, pure water boils at …………….
Solution & Step-by-Step Answer:
100°C
Question 18 Maharashtra Board Solution
Condensation of steam takes place at …………….
Solution & Step-by-Step Answer:
100°C
Question 19 Maharashtra Board Solution
The temperature of a substance can fall below …………….
Solution & Step-by-Step Answer:
0°C
Question 20 Maharashtra Board Solution
Ice melts at …………….
Solution & Step-by-Step Answer:
0°C
Question 21 Maharashtra Board Solution
Each substance has a specific boiling point which is also its …………… point.
Solution & Step-by-Step Answer:
condensation
Question 22 Maharashtra Board Solution
Each substance has a specific melting point which is the same as its …………… point.
Solution & Step-by-Step Answer:
freezing
Question 23 Maharashtra Board Solution
Candles are made by melting …………… wax.
Solution & Step-by-Step Answer:
paraffin
Question 24 Maharashtra Board Solution
Solid carbon-dioxide is …………….
Solution & Step-by-Step Answer:
dry ice
Question 25 Maharashtra Board Solution
Liquid …………… is used in animal husbandry.
Solution & Step-by-Step Answer:
nitrogen
Question 26 Maharashtra Board Solution
Sand is melted to make …………….
Solution & Step-by-Step Answer:
glass
Question 27 Maharashtra Board Solution
Iron is melted to make …………….
Solution & Step-by-Step Answer:
tools
Question 28 Maharashtra Board Solution
Substances can be identified by studying their …………….
Solution & Step-by-Step Answer:
properties
Question 29 Maharashtra Board Solution
Substances that break into small particles are said to be …………….
Solution & Step-by-Step Answer:
brittle
Question 30 Maharashtra Board Solution
The …………… of any liquid is determined by how easily it flows.
Solution & Step-by-Step Answer:
fluidity
Question 31 Maharashtra Board Solution
Between substances of the same volume, the ones with greater density are …………… than those of lesser density.
Solution & Step-by-Step Answer:
heavier
Question 32 Maharashtra Board Solution
The property of a substance of getting …………… is called its solubility.
Solution & Step-by-Step Answer:
dissolved
Question 33 Maharashtra Board Solution
Minerals from the earth’s crust are …………… to obtain metals.
Solution & Step-by-Step Answer:
processed
Question 34 Maharashtra Board Solution
Metals can be converted into …………… by hammering.
Solution & Step-by-Step Answer:
sheets
Question 35 Maharashtra Board Solution
Metals can be stretched and drawn into …………….
Solution & Step-by-Step Answer:
wires
Question 36 Maharashtra Board Solution
All metals are …………… of electricity to a greater or lesser extent.
Solution & Step-by-Step Answer:
conductors
Question 37 Maharashtra Board Solution
Every metal has a …………… colour by which it can be identified.
Solution & Step-by-Step Answer:
specific
Question 38 Maharashtra Board Solution
Metals produce …………… sound.
Solution & Step-by-Step Answer:
ringing
Question 39 Maharashtra Board Solution
Metals form a …………… group of substances.
Solution & Step-by-Step Answer:
separate
Question 40 Maharashtra Board Solution
Heat is the cause of the change of the state of …………….
Solution & Step-by-Step Answer:
substances

Match the columns:

Question 1 Maharashtra Board Solution

Column ‘A’

Column ‘B’

1. Boiling water

a. > 35° C

2. Body temperature

b. 0° C

3. Freezing water

c. < 5° C

4. Air (summer afternoon)

d. < 15° C

5. Inside a fridge

e. < -18° C

6. Air (winter night)

f. 100° C

7. Inside the freezer

g. 37°C

Solution & Step-by-Step Answer:

Column ‘A’

Column ‘B’

1. Boiling water

f. 100° C

2. Body temperature

g. 37°C

3. Freezing water

b. 0° C

4. Air (summer afternoon)

a. > 35° C

5. Inside a fridge

c. < 5° C

6. Air (winter night)

d. < 15° C

7. Inside the freezer

e. < -18° C

Answer in one sentence:

Question 1 Maharashtra Board Solution
What is change of state of substances?
Solution & Step-by-Step Answer:
When a substance changes from one state to another, the process is called change of state of the substance.
Question 2 Maharashtra Board Solution
When does state of substance change?
Solution & Step-by-Step Answer:
State of substance changes when it is heated or cooled.
Question 3 Maharashtra Board Solution
In which state do substances exist in our surroundings?
Solution & Step-by-Step Answer:
The substances exist in solid, liquid and gaseous form in our surroundings.
Question 4 Maharashtra Board Solution
What happens when a substance gains heat?
Solution & Step-by-Step Answer:
When a substance gains heat, it changes its state i.e. from solid to liquid and liquid to gas.
Question 5 Maharashtra Board Solution
What happens when a substance loses heat?
Solution & Step-by-Step Answer:
When a substance loses heat, it changes its state from gaseous to liquid and liquid to solid state.
Question 6 Maharashtra Board Solution
How do we tell how hot or cold a substance is?
Solution & Step-by-Step Answer:
The temperature on the thermometer will tell us how hot or cold a substance is.
Question 7 Maharashtra Board Solution
What is the unit of measuring temperature.
Solution & Step-by-Step Answer:
Degrees Celsius (°C) is the unit of measuring temperature.
Question 8 Maharashtra Board Solution
What is the boiling point of water?
Solution & Step-by-Step Answer:
The boiling point of water is 100° C.
Question 9 Maharashtra Board Solution
What is condensation?
Solution & Step-by-Step Answer:
When vapour cools, it is converted into liquid again. This process is condensation.
Question 10 Maharashtra Board Solution
At what temperature condensation of steam takes place?
Solution & Step-by-Step Answer:
Condensation of steam takes place at 100° C.
Question 11 Maharashtra Board Solution
What is the freezing point of water?
Solution & Step-by-Step Answer:
0° C is the freezing point of water.
Question 12 Maharashtra Board Solution
What is the temperature of air in the freezer of a refrigerator?
Solution & Step-by-Step Answer:
-18° C is the temperature of air in the freezer of a refrigerator.
Question 13 Maharashtra Board Solution
At what temperature ice melts?
Solution & Step-by-Step Answer:
Ice melts at 0° C.
Question 14 Maharashtra Board Solution
How are candles made?
Solution & Step-by-Step Answer:
Candles are made by melting paraffin wax.
Question 15 Maharashtra Board Solution
What is the use of solid carbon-dioxide?
Solution & Step-by-Step Answer:
Solid carbon-dioxide (dry ice) is used to make ice cream and to keep it frozen.
Question 16 Maharashtra Board Solution
What is the use of liquid nitrogen?
Solution & Step-by-Step Answer:
Liquid nitrogen is used in animal husbandry.
Question 17 Maharashtra Board Solution
What is sublimation?
Solution & Step-by-Step Answer:
The change of a solid substance directly into gas or vapour without changing into a liquid is called sublimation.
Question 18 Maharashtra Board Solution
Define brittleness / What is brittleness?
Solution & Step-by-Step Answer:
Some substances break into small pieces or particles. Such substances are said to be brittle. This property of substances is called brittleness.
Question 19 Maharashtra Board Solution
Define hardness / What is hardness?
Solution & Step-by-Step Answer:
The hardness of a substance is determined by how much resistance it offers to the substances being pushed through it.
Question 20 Maharashtra Board Solution
Define elasticity / What is elasticity?
Solution & Step-by-Step Answer:
Some substances change their shape when a force is applied on them but return to their original shape and size when the force is removed. This property is called elasticity.
Question 21 Maharashtra Board Solution
Define fluidity / What is fluidity?
Solution & Step-by-Step Answer:
Liquids flow downward on a sloping surface. This property is called fluidity.
Question 22 Maharashtra Board Solution
How is fluidity of any liquid determined?
Solution & Step-by-Step Answer:
Fluidity of any liquid is determined by how easily it flows.
Question 23 Maharashtra Board Solution
Define density / What is density?
Solution & Step-by-Step Answer:
The mass of different substances having the same volume can be different. This difference is because of the difference in their densities. Between substances of the same volume, the ones with greater density are heavier than those of lesser density.
Question 24 Maharashtra Board Solution
Define solubility / What is solubility?
Solution & Step-by-Step Answer:
The property of a substance of getting dissolved is called its solubility.
Question 25 Maharashtra Board Solution
Define transparency / What is transparency?
Solution & Step-by-Step Answer:
When we can look through a substance and see things on the other side, then that substance is said to be transparent. This property of the substances is called transparency.
Question 26 Maharashtra Board Solution
List some transparent substances.
Solution & Step-by-Step Answer:
Glass, air, clean water and some types of plastic are transparent substances.
Question 27 Maharashtra Board Solution
What are metals?
Solution & Step-by-Step Answer:
Metals are substances like copper, gold, iron, aluminium. They are found in the form of minerals deep inside the earth. Minerals from the earth’s crust are processed to obtain metals.
Question 28 Maharashtra Board Solution
Define malleability. / What is malleability?
Solution & Step-by-Step Answer:
Metals can be converted into sheets by hammering. This property of metals is called malleability.
Question 29 Maharashtra Board Solution
Define ductility. / What is ductility?
Solution & Step-by-Step Answer:
Metals can be stretched and drawn into thin wires. This property of metals is called ductility
Question 30 Maharashtra Board Solution
Name some ductile metals.
Solution & Step-by-Step Answer:
Metals like silver, gold, platinum can be drawn into fine wires.
Question 31 Maharashtra Board Solution
Define electrical conductivity. / What is electrical conduction?
Solution & Step-by-Step Answer:
Electricity flows through metals. All metals are conductors of electricity to a greater or lesser extent.
Question 32 Maharashtra Board Solution
Define thermal conductivity. / What is thermal conductivity?
Solution & Step-by-Step Answer:
Metals allow heat to flow through them. This property is called thermal conductivity
Question 33 Maharashtra Board Solution
What is lustre?
Solution & Step-by-Step Answer:
The typical shine or characteristic colour by which metal can be identified is called lustre.
Question 34 Maharashtra Board Solution
What is sonority of metals? / Define sonority. Answer; Metals produce a ringing sound. This property is called the sonority of metals.

Give scientific reasons for following:

Question 1 Maharashtra Board Solution
Metals are used to make musical instruments.
Solution & Step-by-Step Answer:
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Solution & Step-by-Step Answer:
Metals possess the property of being sonorous, i.e. produce a ringing sound. Hence, they are used to make musical instruments.
Question 2 Maharashtra Board Solution
Ornaments are made up of metals.
Solution & Step-by-Step Answer:
Metals have the property of being malleable, ductile, lustrous. Hence, ornaments are made up of metals.
Question 3 Maharashtra Board Solution
Why should we not put our hand or finger in the water to judge the hotness of water?
Solution & Step-by-Step Answer:
We should never put our hand or finger in the water to judge how hot it is because that is not an accurate measure. Besides if the substance is very hot, we could get scalded.

Can you tell?

Question 1 Maharashtra Board Solution
Why are electric boards fitted on the wall made of plastic or wood?
Solution & Step-by-Step Answer:
Plastic or wood are bad conductors of heat and electricity. Electric boards are made up of plastic or wood. So that while touching we will not get electric shock.
Question 2 Maharashtra Board Solution
The handle of cooker is made of plastic. Why?
Solution & Step-by-Step Answer:
Cooker is made of metal. When food is cooked in it, it gets heated and the whole of its body becomes hot due to thermal conductivity. Hence with the plastic handle we can easily lift the hot cooker as plastic is a bad conductor of heat.
Question 3 Maharashtra Board Solution
Use your brain power! On opening a box of camphor, its smell spreads all around. Why does this happen?
Solution & Step-by-Step Answer:
Question 4 Maharashtra Board Solution
Identify the objects shown in fig. 5.14. From which substances are they made? What are these substances called as a group?
Solution & Step-by-Step Answer:
In fig 5.14, the metallic bars are shown, these bars are made up of shiny solid. These substances are called metals.
Question 5 Maharashtra Board Solution
Name the solid, liquid and gaseous states of water.
Solution & Step-by-Step Answer:
Question 6 Maharashtra Board Solution
Read this list of substances: spirit, camphor, petrol, ghee, coconut oil, naphthalene balls, ammonium chloride (navsagar).

Question a.
Which one freezes in winter?

Solution & Step-by-Step Answer:

Coconut oil, ghee.

Question b.
Which liquids have you seen change into a vapour?
Answer:
Spirit, petrol.

Question c.
Which solid directly changes into gaseous state?
Answer:
Camphor, naphthalene balls, ammonium chloride.

Question 7 Maharashtra Board Solution
The chart given below shows the boiling point and freezing point of some substances. State whether these substances are solid, liquid or gaseous at room temperature.

Substance

Freezing Point

Boiling Point

Candle

60 °C

350 °C

Plastic

> 250 °C

954 °C

Iron

1535 °C

2862 °C

Solution & Step-by-Step Answer:
Candle, plastic and iron are in solid state at room temperature.

Distinguish between solids, liquids and gases.
Answer:

Solids

Liquid                                                  Gases

e.g.: A piece of iron

e.g.: Water, spirit, oil

e.g.: Air

Has a shape of its own, Retains shape, no matter how it is kept.

Does not have a shape of its own. Takes the shape of the container.

Does not have a shape of its own. Occupies all the available space.

Has a definite volume. Solids like sugar, sand when poured on a flat surface, form a heap.

It has a specific volume. Occupies definite portion of a container. Spreads on a flat surface on pouring. Flows downwards along a slope. Takes the shape of the surface.

Does not have a definite volume. On changing the pressure on a gas in a closed container, its volume also changes.

Distinguish between Boiling and Melting.
Answer:

Boiling

Melting

1. When heat is supplied to liquids, they boil.

1. When heat is supplied to solids, they melt.

2. Boiling leads liquids to vapour/gaseous state.

2. Melting leads solids to liquid state.

3. The temparature at which liquid starts boiling continuously is called boiling point.

3. The temperature at which solid turns to liquid completely is called melting point.

Answer the following briefly:

Question 1 Maharashtra Board Solution
List properties of solids
Solution & Step-by-Step Answer:
Question 2 Maharashtra Board Solution
List properties of liquids.
Solution & Step-by-Step Answer:
Question 3 Maharashtra Board Solution
List properties of gases.
Solution & Step-by-Step Answer:
Question 4 Maharashtra Board Solution
Explain with example how liquids take the shape of the surface.
Solution & Step-by-Step Answer:
Liquids have a specific volume. They occupy definite portion of a container. Liquids spreads on a flat surface on pouring. Liquids flow downwards along a slope.
Question 5 Maharashtra Board Solution
Explain Ebullition.
Solution & Step-by-Step Answer:
Question 6 Maharashtra Board Solution
Explain: Boiling point and condensation point of water are one and the same.
Solution & Step-by-Step Answer:
Water boils at 100°C. i.e. boiling point of water is 100°C. Condensation of steam also takes place at 100° C. Thus boiling point and condensation point of water are one and the same.
Question 7 Maharashtra Board Solution
Explain freezing point of water.
Solution & Step-by-Step Answer:
Question 8 Maharashtra Board Solution
Explain: Freezing point and melting point of water are same.
Solution & Step-by-Step Answer:
Question 9 Maharashtra Board Solution
List various uses of changes in physical state.
Solution & Step-by-Step Answer:
Question 10 Maharashtra Board Solution
List the properties of substances:
Solution & Step-by-Step Answer:
The properties of substances are
Question 11 Maharashtra Board Solution
List properties of metals:
Solution & Step-by-Step Answer:
The properties of metals are
Question 12 Maharashtra Board Solution
How can we change the volume of a gas?
Solution & Step-by-Step Answer:
On changing the pressure on a gas in a closed container we can change its volume.

Can you tell?

Question 1 Maharashtra Board Solution
Does water change into vapour the moment we place the vessel on a stove? Does water kept in fridge change at once into ice?
Solution & Step-by-Step Answer:
No, it doesn’t. Water slowly changes from one state to another.
Question 2 Maharashtra Board Solution
How do we tell how hot or cold a substance is?
Solution & Step-by-Step Answer:
A thermometer is used to measure the temperature of the subatance which tell us hot or cold it is.
Question 3 Maharashtra Board Solution
How will you identify the following

Question i.
A glass: Is it made of plastic, steel or glass?

Solution & Step-by-Step Answer:
Glass is made of glass as it is transparent.

Question ii.
A rod: Iron or aluminium.
Answer:
A rod is made of iron as it is heavy.

Question iii.
A door: Wooden or glass?
Answer:
A door is wooden as it is opaque.

Question iv.
A white powder: Salt or chalk powder?
Answer:
If powder dissloves in water it is salt and if it does not dissolves in water it is chalk.