English Medium Class 10 - CBSE Question Bank Solutions for Science

"Two different forms of carbon - diamond and graphite have different structure and very different physical properties even though their chemical properties are same." Explain why.

Draw a diagram showing flow of energy from solar input to a food chain having four trophic levels in an ecosystem. List two inference that can be drawn from the energy flow diagram.

Study the given figure of a Food web and identify the primary consumer in the food web:

State reasons for Myopia. With the help of ray diagrams, show the:

1. image formation by a myopic eye, and
2. correction of myopia using an appropriate lens.

A person is unable to see clearly a poster fixed on a distant wall. He however sees it clearly when standing at a distance of about 2 m from the wall.

1. Draw ray diagram to show the formation of image by his eye lens when he is far away from the wall.
2. List two possible reasons of this defect of vision.
3. Draw ray diagram to show the correction of this defect using appropriate lens.

Observe the following diagram and answer questions following it: 

1. Identify the defect of vision shown.
2. List its two causes.
3. Name the type of lens used for the correction of this defect.

Define the following terms in the context of a diverging mirror:

1. Principal focus
2. Focal length

Draw a labelled ray diagram to illustrate your answer.

Write the balanced equation for the following chemical reaction.

\[\ce{Hydrogen + Chlorine -> Hydrogen chloride}\]

Write the balanced equation for the following chemical reaction.

\[\ce{Barium chloride + Aluminium sulphate -> Barium sulphate + Aluminium chloride}\]

Write the balanced equation for the following chemical reaction.

\[\ce{Sodium + Water -> Sodium hydroxide + Hydrogen}\]

Give two examples of amphoteric oxides.

Name two metals which will displace hydrogen from dilute acids, and two metals which will not.

Make a diagram to show how hypermetropia is corrected. The near point of a hypermetropic eye is 1 m. What is the power of the lens required to correct this defect? Assume that the near point of the normal eye is 25 cm.

What are amphoteric oxides?

Give reason:

Sodium, potassium and lithium are stored under oil.

Which of the following oxide(s) of iron would be obtained on the prolonged reaction of iron with steam?

Example of an amphoteric oxide is:

Which of the following metals liberate hydrogen with 5% HNO₃?

(i) Cu

(ii) Zn

(iii) Mn

(iv) Mg

Which one of the following metals does not react with cold as well as hot water?

Generally, metals react with acids to give salt and hydrogen gas. Which of the following acids does not give hydrogen gas on reacting with metals (except Mn and Mg)?