English Medium कक्षा १० - CBSE Question Bank Solutions for Science

Write the balanced chemical equation for the following reaction.

\[\ce{Aluminium + Copper chloride -> Aluminium chloride + Copper}\]

Write the balanced chemical equation for the following reaction.

\[\ce{Zinc + Silver nitrate -> Zinc nitrate + Silver}\]

Write the balanced chemical equation for the following reaction.

\[\ce{Calcium hydroxide + Carbon dioxide → Calcium carbonate + Water}\]

You have been provided with three test tubes. One of them contains distilled water and the other two contain an acidic solution and a basic solution, respectively. If you are given only red litmus paper, how will you identify the contents of each test tube?

A solution turns red litmus blue, its pH is likely to be ______.

What is the difference between a reflex action and walking?

How does chemical coordination take place in animals?

What is the difference between the manner in which movement takes place in a sensitive plant and the movement in our legs?

If a trait A exists in 10% of a population of an asexually reproducing species and a trait B exists in 60% of the same population, which trait is likely to have arisen earlier?

If a trait A exists in 10% of a population of an asexually reproducing species and a trait B exists in 60% of the same population, which trait is likely to have arisen earlier?

How does the creation of variations in a species promote survival?

How does the creation of variations in a species promote survival?

Define the term.

Power of accommodation of the eye.

The human eye can focus objects at different distances by adjusting the focal length of the eye lens. This is due to ______.

What is a good source of energy?

What is a good fuel?

If you could use any source of energy for heating your food, which one would you use and why?

An element P (atomic number 20) reacts with an element Q (atomic number 17) to form a compound. Answer the following questions giving reason:

Write the position of P and Q in the Modern Periodic Table and the molecular formula of the compound formed when P reacts with Q.

With the help of ciliary muscles the human eye can change its curvature and thus alter the focal length of its lens. State the changes that occur in the curvature and focal length of the eye lens while viewing (a) a distance object, (b) nearby objects.

Explain, why a normal eye is not able to see distinctly the objects placed closer than 25 cm, without putting any strain on the eye.