Maharashtra Board Textbook Solutions

Standard 6 – Science

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

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

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

💬 2. Discuss.

(a) Riya pours some water from her bottle into another bottle. Does it change the shape of the water?
Ans: Yes, the shape of water changes and it takes the shape of the new bottle. This is because water is a liquid and liquids do not have a shape of their own. They take the shape of the container.

(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?
Ans: No, the shape of the stone does not change. This is because a stone is a solid and solids have a fixed shape.

🧪 3. Write the properties of these substances.

Ans:

Substance	State	Properties
Water	Liquid	Fluidity, density, solubility, transparency
Glass	Solid	Brittleness, hardness, density, transparency
Chalk	Solid	Brittleness, density
Iron ball	Solid	Hardness, density, malleability, ductility, conductivity, lustre, sonority
Sugar	Solid	Brittleness, density, solubility
Salt	Solid	Brittleness, density, solubility
Flour	Solid	Density, slight solubility
Coal	Solid	Brittleness, density
Soil	Solid	Density
Pen	Solid	Hardness, density
Ink	Liquid	Fluidity, density, solubility
Soap	Solid	Hardness, solubility

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

Ans: Sublimation is the process in which a solid substance directly changes into gas without changing into liquid first. Examples of substances that undergo sublimation are iodine, naphthalene balls, and camphor.

🔧 5. What is it made from? Why?

(a) A sickle to cut sugarcane.
Ans: A sickle is made from iron or steel because these metals are hard, strong, and durable. These properties make it suitable for cutting sugarcane.

(b) The sheets used for roofing.
Ans: Roofing sheets are made from aluminium because it is light in weight, strong, and does not rust easily. It also protects from rain and sunlight.

(c) A screwdriver
Ans: A screwdriver is made from steel because it is strong and durable. It helps in tightening and loosening screws efficiently.

(d) A pair of tongs.
Ans: Tongs are made from stainless steel because it is strong, durable, and rust-free. It is safe and useful for handling hot objects in the kitchen.

(e) Electric cables.
Ans: Electric cables are made from copper or aluminium because these metals are good conductors of electricity.

(f) Ornaments.
Ans: Ornaments are made from metals like gold and silver because metals are malleable and ductile. They can be shaped into thin sheets and wires.

(g) Pots and pans.
Ans: Pots and pans are made from metals because metals are good conductors of heat and help in cooking food properly.

🤔 6. What will happen if….? And why?

(a) Nails are made of plastic.
Ans: Plastic nails will not be useful because plastic is not hard enough. It cannot withstand hammering and cannot pierce materials properly.

(b) A bell is made of wood.
Ans: A wooden bell will not produce a clear ringing sound because wood does not have the property of sonority like metals.

(c) Rubber is not fitted on a pair of tongs.
Ans: Without rubber covering, the metal tongs will become hot due to heat conduction and may burn our hands.

(d) A knife is made of wood.
Ans: A wooden knife will not be able to cut objects because wood is not hard or sharp like metal.

(e) An axe is made of rubber.
Ans: A rubber axe will not be useful because rubber is soft and elastic. It cannot cut wood like a metal axe.

🧩 7. Who am I?

(a) I’m found in a thermometer, I measure your temperature.
Ans: Mercury

(b) I make things hot or cold.
Ans: Heat

(d) I dissolve in water, but not in kerosene.
Ans: Salt

🌍 8. Why does this happen?

(a) Coconut oil thickens in winter.
Ans: In winter, the temperature is low. Coconut oil reaches its freezing point and starts solidifying, so it appears thick.

(b) Kerosene left open in a dish disappears.
Ans: Kerosene evaporates when left open. Due to the surrounding temperature, it changes into vapour and disappears.

(c) The fragrance of incense sticks lighted in one corner of a room spreads to the other corner.
Ans: The fragrance spreads because gases can move freely in all directions. The scented smoke mixes with air and spreads throughout the room.

(d) What you see in the picture.
Ans: The air-filled balloon floats on water because it is filled with gas and has lower density. The apple sinks because it is a solid and has higher density than water.