Is Matter around us Pure (Elements & Compounds)

Elements and Compounds do not fall under the category of:

• Pure Substances

• Mixtures

Most prominent properties of metals are

• Malleability

• Sonorous

• They are in variety of colours

• lustrous

True or False:

Gallium and Cesium do not become liquid slightly above room temperature.

• True

• False

Who was the first person to give the experimentally useful definition of an element?

• Antoine Laurent Lavoisier

• Robert Boyle

True or False:

There are only two elements which remain liquid at room temperature.

• True

• False

How many elements are naturally occurring?

• 100

• 102

• 92

• 93

How many elements remain in the gaseous state at room temperature?

• 71

• 11

• 92

• 52

Assertion (A): Wood is not considered as a compound whereas Water is.

Reason (R): Water is contains more than two types of elements.

• Both A and R are true and R is the correct explanation of A.

• Both a and R are true but R is not the correct explanation of the A.

• A is true and R is false.

• A is false and R is true.

Assertion (A): After heating Iron fillings and Sulphur powder together, the substance so formed loses it's magnetism.

Reason (R): The substance so formed is a homogeneous mixture.

• Both A and R are true and R is the correct explanation of A.

• Both a and R are true but R is not the correct explanation of the A.

• A is true and R is false.

• A is false and R is true.

Of the four boxes shown, which one represents a model of elements only?

• B and D

• A, C and D

• B and C

• A and C