English Medium Class 10 - CBSE Question Bank Solutions for Science

Which among the following is not a base?

Myopia and hypermetropia can be corrected by:

A person cannot see distinctly objects kept beyond 2 m. This defect can be corrected by using a lens of power:

Assertion: Myopia is the defect of vision in which a person cannot see distant objects clearly.

Reason: This due to eye-ball being too short.

Assertion: Concave mirrors are used as reflectors in torches, vehicle head lights and in search lights.

Reason: When an object is placed beyond the center of curvature of a concave mirror, the image formed is real and inverted.

Which of the following statement is correct?

Myopia may arise due to ____________.

The unit of specific resistance is ____________.

The slope of voltage (V) versus current (I) is called:

The variable resistance is called ____________.

The temperature of a conductor is increased. The graph best showing the variation of its resistance is:

A student carries out an experiment and plots the V-I graph of three samples of nichrome wire with resistances R₁, R₂ and R₃ respectively. Which of the following is hue?

Assertion: The statement of Ohm’s law is K = IR.

Reason: V = IR is the equation which defines resistance.

Assertion: Decomposition of vegetable matter into compost is an endothermic reaction.

Reason: Decomposition reaction involves breakdown of a single reactant into simpler products.

Marble statues are corroded or stained rain water. Identify the main reason.

Balance the following chemical equation and identify the type of chemical reaction.

`"HgO"("s") overset("(heat)")(->) "Hg"("l") + "O"_2("g")`

Balance the following chemical equation and identify the type of chemical reaction.

`"H"_2"O"_2("l") overset("U  V")(->) "H"_2"O"("l") + "O"_2("g")`

On heating blue coloured powder of copper (II) nitrate, in a boiling tube, copper oxide (black), oxygen gas and a brown gas X is formed

1. Write a balanced chemical equation of the reaction.
2. Identify the brown gas X evolved.
3.  Identify the type of reaction.
4. What could be the pH range of aqueous solution of the gas X?

Which of the following is not a base? 

Match the important chemicals given in Column (A) with the chemical formulae given in Column (B)