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The organ system shown here helps us to breathe. Which of the following gases does it inhale and exhale?


A Inhale oxygen, exhale carbon dioxide
B Inhale nitrogen, exhale oxygen
C Inhale carbon dioxide, exhale oxygen
D Inhale carbon dioxide, exhale methane

Which one of the following is true for all chemical reactions?

AThere is a change in volume
BHeat is evolved
CChemical bonds are broken or formed
DThere is a change in mass

Which of the following is not correctly matched?

A
B
C
D

A few materials are given in the box.
(i) Butter paper (ii) Cellophane sheet
(iii) Window pane (iv) Glass
(v) Water (vi) Air
The transparent materials among these are

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

Identify the correct statements among the following.
(i) A piece of wood is lighter than water.
(ii) Cotton will float on water if placed on wax paper.
(iii) An equal volume of aluminium will be heavier than iron.
(iv) An iron nail will sink in water.

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

Read the given statements and select the option that correctly identifies true (T) and false (F) ones.
1. People who do more physical work need more carbohydrate-rich food.
2. Minerals help in the formation of bones, teeth and blood.
3. Eating too much of roughage containing food can make you obese.

There was a large number of dead fish drifting towards shore. Many dead birds with sticky, black coating feathers could also be seen there. A/An ______ might have occurred nearby.

A Tsunami
B Volcanic eruption
C Oil spill
D Earthquake

Natasha arranged four set-ups as given below:

III. Solutions in test tubes 1 and 3, turn red with methyl orange.
IV. With phenolphthalein indicator, solutions turn pink in test tubes 2 and 4.
V. Turmeric solution shows red colour with solutions in test tubes 1 and 3 while yellow colour with solutions in test tubes 2 and 4.

A II, III and IV only
B I, III and V only
C I and V only
D II, III and V only

A pendulum swings backwards and forwards passing through Y, middle point of the oscillation.

The first time the pendulum passes through Y, a stopwatch is started.
The twenty-first time the pendulum pass through Y, the stopwatch is stopped. The reading is T.
What is the time period of the pendulum?

A T/40
B T/21
C T/20
D T/10

Which point on the given graph shows the boiling point of a given substance?


A Q
B R
C S
D T