Question

VII. Read: 30min
Write: 30min
Page No: 23, 24
1. Write a short note on physical properties of Materials such as Hardness and Appearance
2. How can you differentiate soluble and in soluble sub-stances explain with examples?​

Answer 1

Answer:

Soluble means capable of dissolving in a solvent whereas insoluble means incapable of dissolving in a solvent. Polar and non-polar substances are soluble in polar and non-polar solvents respectively, whereas polar and non-polar substances are insoluble when mixed with each other.Apr 4, 2012

Answer 2

physical properties of metals and non metals(materials)

hardness: metals are generally hard except mercury while non metals are commonly soft.

Appearance: metals are lustrous while non metals are not lustrous.

Malleability: metals can be hammered into very thin sheets while non metals are brittle and cannot be hammered into thin sheets.

Ductility: matals can be drawn into wires while non metals cannot.

Melting and boiling points: metals have high melting and boiling points while non metals have low melting and boiling points.

ans 2. substances which dissolve in water are called soluble substances.

ex: sugar in water.

substances which do not dissolve in water are called insoluble substances.

ex: sand in water.