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Rahul, a science teacher performed the following experiment to study the reaction between dilute sodium hydroxide and dilute sulphuric acid.

Select the correct statement(s) about the given experiment.
I. On mixing these substances, three new products will be formed, including water.
II. The chemical reaction involved is known as neutralisation reaction and is exothermic in nature.
III. The salt formed in this reaction is acidic in nature.

AII only
BII and III only
CIII only
DI and III only

Match column I with column II and select the correct option from the given codes.


A(i)–S; (ii)–Q; (iii)–R; (iv)–P
B(i)–R; (ii)–Q; (iii)–P; (iv)–S
C(i)–Q; (ii)–P; (iii)–R; (iv)–S
D(i)–R; (ii)–S; (iii)–Q; (iv)–P

A rubber ball of mass 100 g falls from a height of 4.90 m and after hitting the ground it rebounds to a height of 2.45 m. The impulse imparted to the ball by the ground if the time for which they are in contact was 0.2 s is

A1.67 N s
B2.38 N s
C3.34 N s
D0.84 N s

Seeds which have wings or tufts of hair on them are generally dispersed by ____.

AExplosion
BAir
CWater
DAnimals

Three identical blocks each of mass m, are pushed by a force F on a frictionless table as shown in figure.


A Net force on X is F.
B Force applied by X on Y is F/3.
C Force applied by Y on Z is equal to net force on X.
D Net force on Y is equal to zero.

Find the number of triangles formed in the given figure.


A11
B15
C18
DNone of these

Which of the following statements is incorrect?

A Motion of a vehicle on a straight road is not rectilinear motion.
B Motion of honeybees is the example of random motion.
C Cubit is the length of a forearm.
D Centigrade is not the SI unit of temperature.

Study the given food web.

If somehow, the population of organism V is removed from this food web, then population of organism __(i)__ will be affected positively and that of organism ___(ii)___ will be affected negatively.

Study the given Venn diagram and select the incorrect statement regarding it.


AP could be a vitamin that helps keep gums healthy.
BQ could be a vitamin that help to build strong bones and teeth.
CP could be a vitamin that helps in clotting of blood.
DDeficiency of P could cause scurvy and that of Q causes prolonged bleeding.