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When a grey coloured metal (P) object is left exposed to damp air for a considerable time, it gets a reddish-brown flaky coating by the process called (Q) which eats up the whole object gradually. It is said that the presence of (R) and (S) are necessary for this process to take place. If this object is galvanised by metal (T), then the process (Q) does not occur.
Now select the incorrect statement(s) from the following.
I. The metal P of which the object is made is iron.
II. The process Q is known as rusting which is a chemical change.
III. R and S are carbon dioxide and water.
IV. The metal T is copper.

A I and II only
B III and IV only
D IV only
D I and III only

Aditya wants to find out the effect of temperature on evaporation. He set-up various possible conditions and tabulated them as follows :

Which pair of set-ups should he use?

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

The food prepared by the leaves is used by the plants for their daily activities. The excess food gets stored as starch in ______.

ARoots
BStems
CFruits
DAll of these

Select the incorrect match.

A Fermentation – Occurs in absence of oxygen and yields very little energy
B Internal respiration – Exchange of gases between blood and body cells
C Exhalation – Decrease in air pressure inside the lungs causes air to move out from the lungs
D Stomata – Present on the surface of leaves and young stems.

From the given v – t graph, it can be inferred that the object is


A In uniform motion
B At rest
C In non-uniform motion
D Moving with uniform acceleration.

A man is going on a picnic with his two children and a woman. The woman is his sister. The woman is children’s _________.

A Mother
B Grandmother
C Aunt
D Cousin

Study the classification carefully and choose the correct answer from the table.

Unscramble the letters to find the name of the organ system shown in the given figure.


A YROTERCXE METSYS
B YROTALUCRIC METSYS
C YROTARIPSER METSYS
D LATELEKS METSYS

Select the odd one out.

A Jupiter
B Saturn
C Uranus
D Neptune

Consider the following figures (I) and (II) and identify the incorrect statement.


A Figure I represents a change in which the components of the mixture can be easily separated by magnetic separation.
B Figure II represents a change which is irreversible.
D Figure I represents a change in which no new substance is formed.
D Figure II represents a change in which a substance is formed which has the properties of both iron and sulphur.