Change Around Us

Burning of paper is a __________ change
1. physical
2. chemical
3. physical and chemical
4. neutral
The burning of matchstick is an example for chemical reaction based on
1. contact
2. electricity
3. light
4. catalyst
_ metal undergoes rusting.
1. tin
2. sodium
3. copper
4. iron
The pigment responsible for browning of apples is_
1. hydrated iron (II) oxide
2. melanin
3. starch
4. ozone
Brine is a concentrated solution of _.
1. sodium sulphate
2. sodium chloride
3. calcium chloride
4. sodium bromide
Limestone contains
1. calcium chloride
2. calcium carbonate
3. calcium nitrate
4. calcium sulphate
Which of the following factor induces electrolysis?
1. heat
2. light
3. electricity
4. catalysis
In Haber's process of producing ammonia _ is used as a catalyst.
1. nitrogen
2. hydrogen
3. iron
4. nickel
Dissolved gases like sulphur dioxide and nitrogen oxide in rain water causes
1. acid rain
2. base rain
3. heavy rain
4. neutral rain
_ is responsible for Global Warming
1. carbon-di-oxide
2. methane
3. chloro-fluoro-carbons
4. all of the above