Pure Substances

Q.

Is water an element or a compound? Give reason in support of your answer

Q. What are the two types of pure substances?

1. Elements and subatomic particles
2. Protons and electrons
3. Atoms and compounds
4. Homogenous and heterogeneous

Q.

Distinguish Between Physical And Chemical Properties Of Matter.

Q.

Classify the following into element, compound and mixture:

(i) coal (ii) methane (iii) copper (iv) carbon dioxide (v) steam (vi) honey (vii) granite (viii) blood (ix) sugar (x) germanium.

Q.

Which among the following is a pure substance?

1. Soft drink

2. Lemonade

3. Muddy Water

4. Salt crystals

Q.

Is ice a pure substance?

1. No

2. Yes

Q.

Identify the physical property that can help to check the purity of a substance.

1. Both Atmosphericpressure and Homogeneity

2. Homogeneity

3. Atmospheric pressure

4. Melting and boiling point

Q.

Is iced water a pure substance? Why?

Q.

A pure substance is made up of __________ .

1. same type of particles
2. different type of particles
3. different type of particles in a fixed ratio
4. different type of particles in any ratio

Q.

Why is distilled water the purest form of water. Give its uses.

Q. Pure substances can be classified as _____________ and ___________.

1. elements, compounds
2. elements, mixtures
3. compounds, mixtures
4. molecules, mixtures

Q. Write the steps you would use for making tea.
Use the words given below and write
the steps for making tea?

Solution, solvent, solute, dissolve, soluble,
insoluble, filtrate and residue

Q.

2. Define the following terms:

ii. Compound

Q. Pure substances can be further divided into ________ and _________.

1. mixtures, compounds
2. elements, compounds
3. elements, mixtures
4. mixtures, solution

Q. Which one of the following is a pure substance?​

1. Iron
2. Tea
3. Air
4. Soda

Q. Define what a sublimable substance is. ​
Give few examples.​

Q.

“The properties of a compound are the same as the properties of the elements that make up the element”. Is this statement correct? If not, correct it.

Q. Matter with definite and constant composition, and distinct chemical properties is known as a/an :

1. element

2. mixture

3. pure substance

4. impure substance

Q. Pure substances are classified as:

1. elements and compounds
2. elements and mixtures
3. compounds and mixtures
4. molecules and mixtures

Q.

Water has fixed melting and boiling points.

1. True
2. False

Q.

Stretching a rubber band is a physical change.

1. True
2. False

Q.

The composition of a pure substance cannot be altered by any _______ means.

Q.

Chlorine is an element and Sodium chloride is a compound.

1. True
2. False

Q. Matter with definite and constant composition, and distinct chemical properties is known as a/an :

1. solution
2. mixture
3. pure substance
4. impure substance

Q. Pure substances can be further divided into ________ and _________.

1. elements, compounds
2. elements, mixtures
3. mixtures, solution
4. mixtures, compounds

Q.

Differentiate between the following changes with suitable examples.

Desirable and undesirable changes.

Q. Which of the following is not a pure substance?

1. Copper
2. Hydrogen
3. Oxygen
4. Alloy

Q.

What are the various factors based on which substances are separated? [1 MARK]

Q. In summers, electric wires sag a little as ___________ on heating.

1. non-metals expand
2. metals expand
3. metals contract
4. non-metals contract

Q.

Which of these physical properties do not change when two different substances are used to form a mixture?

1. Atmospheric pressure

2. Melting and boiling point

3. Homogeneity

4. Both Atmosphericpressure and Homogeneity