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Change X : Cooling a mixture of air and kerosene vapours so that liquid kerosene condenses out. Change Y : Burning a mixture of air and kerosene vapours.
What type of changes X and Y are?

AX - Chemical change, Y - Reversible change
BX - Physical change, Y - Chemical change
CX - Chemical change, Y - Physical change
DX - Reversible change, Y - Physical change

Which of the following statements are true?
(i) A shadow is formed on the same side of the object as the source of light.
(ii) The image formed by a pinhole camera is always erect.
(iii) We see stars because they reflect light from the sun.
(iv) The shadow of a pole is longest in the evening and shortest at the noon.
(v) Mirrors are good reflectors of light.

A(i), (ii) and (iii) only
B(i), (ii) and (iv) only
C(iv) and (v) only
D(i), (ii), (iii) and (v) only

Read the given passage where some of the words have been italicised. Pure wool has the natural ability to undergo biodegradation. Due to its low water and nitrogen content, wool naturally resists fire. When wool is heated, it melts and gives smell of charred meat. Wool is obtained from sheep, goat, camel, yak, rabbit etc. Angora wool is obtained from Angora goat whereas mohair is obtained from Angora rabbit. Cashmere is a fine, strong, light and soft wool obtained from yak.
Select the incorrect statement regarding this.

ALow should be replaced with high.
BMelts should be replaced by burns whereas charred meat should be replaced with burning hair.
CPositions of Angora wool and mohair should be interchanged.
DYak should be replaced with camel.

In which of the following groups, odd one out is circled incorrectly?

ASand, Sandust, Talcum powder
BWood, Plastic, Aluminium,
C Iron, Copper, Zinc
DGlass marble, Stapler pin, Needle

A few processes are listed in the table.

Which of the processes listed in the table can be used to separate solids from liquids?

A(ii) and (v) only
B(iii), (iv) and (vi) only
C(i) and (ii) only
D(i), (ii), (v) and (vi) only

_________ can be recharged, but _________ cannot be recharged. Chemical reactions involved in primary cells are _________ and in secondary cells are _________.

APrimary cells, secondary cells, irreversible, reversible.
BSecondary cells, primary cells, irreversible, reversible.
CSecondary cells, primary cells, reversible, irreversible.
DPrimary cells, secondary cells, reversible, irreversible.

Refer to the given Venn diagram and select the INCORRECT option regarding organs P, Q and R.


A P could be a muscular organ which churns the food and helps in mixing it with acid.
B Q receives digestive juices from R and liver for complete digestion of all food components.
C R could be pancreas which secretes different digestive juices for digestion of proteins, fats and carbohydrates.
D P could be large intestine which is the longest and widest part of the gut.

Which of the following statements hold true for the root system shown in the given figure?

(i) It is a fibrous root system.
(ii) The branches that arise from the main root are called fibrous roots.
(iii) It is a tap root system.
(iv) Examples of this type of root system are pea, tulsi, radish, carrot and turnip.

A (i) and (iii) only
B (ii) and (iv) only
C (iii) and (iv) only
D (ii) and (iii) only

A few substances are listed in the box.

The given graph shows rate of CO₂ uptake over 24 hours by two potted plants X and Y kept in direct sunlight with all similar conditions viz. same sized pots with equal amount of soil and manure, adequate moisture and air.

Select the best possible option regarding X and Y.

APlant X is actively photosynthesising between 20 hrs to 24 hrs.
BPlant Y shows stomatal closure between 10 hrs to 18 hrs.
CPlant X shows maximum transpiration between 12 to 14 hrs.
DBoth B and C