Amount of substance is

(a)

directly proportional to the number of atoms

(b)

inversely proportional to the number of atoms

(c)

directly proportional to the square of number of atoms

(d)

inversely proportional to the square of number of atoms

The centre of a sphere of which the reflecting surface of a spherical mirror is a part is called

(a)

pole

(b)

centre of curvature

(c)

cradius of curvature

(d)

aperture

Which one of metal possess low tensile strength?

(a)

Silver

(b)

Copper

(c)

Zinc

(d)

Aluminium

Limestone contains ______ mainly.

(a)

Calcium chloride

(b)

calcium carbonate

(c)

calcium nitrate

(d)

calcium sulphate

Floridian starch is a reserve food material of

(a)

Chloroplyceae

(b)

Phaeophyceae

(c)

Rhodophyceae

(d)

Cyanophyceae

Osmosis is the movement of water molecules from a ______.

(a)

Higher concentration to a region of lower concentration.

(b)

Lower concentration to a region of higher concentration.

(c)

Both of these

(d)

None of these

If you apply equal amount of heat to a solid, liquid and gas individually, which of the following will have more expansion?

(a)

Solid

(b)

Liquid

(c)

Gas

(d)

All of above

Carbon dioxide with water changes

(a)

blue litmus to red

(b)

red litmus to blue

(c)

blue litmus to yellow

(d)

doesn’t react with litmus

Why do underwater divers wear fin-like flippers on their feet ?

(a)

To swim easily in water

(b)

To look like a fish.

(c)

To walk on water surface

(d)

To walk over the bottom of the sea (sea bed).

The sperm is produced by ____________

(a)

penis

(b)

ovary

(c)

uterus

(d)

testes