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Strips of metal X were dipped into two different solutions as shown :

A greyish metallic deposit was found on both strips.
Which of the following could be metal X?

ACu
BMg
CPb
DFe

Rupali, a class 10 student has set up the apparatus as shown in the figures.

Which of the following observations is correct?

A Temperature of beakers I, II and III will be raised as dissolution of salts is an exothermic process.
B Temperature of beakers III and IV will be raised while temperature of beakers I and II will fall.
C Temperature will rise only in beaker IV as redox reactions are exothermic.
D None of these

8 g of E₂O₃ contains 5.6 g of 'E'. How many moles of E does 16.8 g of the element 'E' contain?

A0.1
B0.2
C0.3
D0.75

In the given circuit, the total current supplied by the battery is



A1 A
B2 A
C3 A
D6 A

Nine identical resistors of resistance 1 Ω each are connected as shown in the given figure.



Which of the following bar graphs best shows the equivalent resistance between terminals A and B, between terminals B and C, between terminals C and A?

A

B

C

D

A compound is prepared from gypsum upon heating to a temperature of 373 K and it changes back to gypsum on adding water. Which is the incorrect statement about the compound?

A The compound is used for setting fractured bones.
B The compound is called plaster of Paris which is calcium sulphate dihydrate with a formula CaSO₄.2H₂O.
C If heated at higher temperature, the compound becomes dehydrated and is called dead burnt plaster.
D Both (A) and (B).

Study the given food web. Which of the following would lead to decrease in the water snail population?

P. Increase in Hydrilla population
Q. Increase in tadpole population
R. Decrease in kingfisher population
S. Increase in dragonfly nymphs population

A Q only
B P and R only
C Q, R and S only
D S only

The given figure shows a food web in a forest area. In the forest, large amount of insecticides are blown with wind from a nearby field. What will be the effect on the given food web?


A Increase in the number of sparrows
B Increase in the number of frogs
C Greater reduction in the number of hawks than in the number of caterpillars
D Greater reduction in the number of caterpillars than in the number of flies

Observe the given figure carefully.

Which of the following observations are correct?
I. A white coloured residue is left behind in the test tube.
II. Water droplets are observed on the upper cooler part of the test tube.
III. On adding water to the residue the colour changes to green.

A I and III only
B II and III only
C I and II only
D All of these

In a certain code language, ‘si po re’ means ‘book is thick’, ‘ti ma re’ means ‘bag is heavy’, ‘ka si’ means ‘interesting book’ and ‘de ti’ means ‘that bag’. Which of the following means ‘that is interesting’ in that code language?

Aka de re
Bti po ka
Cde si re
Dka re ma