English Medium कक्षा ९ - CBSE Question Bank Solutions for Science

The maximum speed of vibrations which produce audible sound will be in :

The speeds of sound in four different media are given below. Which of the following is the most likely speed in m/s with which the two under water whales in a sea talk to each other when separated by a large distance?

What is a neutron? State its relative mass and charge.

What is the significance of the symbol of an element ? Explain with the help of an example.

Explain the significance of the symbol H.

The symbol of a metal element which is used in making thermometers is :

The Latin language name of an element is natrium. The English name of this element is :

A man is kidnapped, blindfolded and imprisoned in a big room. How could the man tell if he was in : a city 

A man is kidnapped, blindfolded and imprisoned in a big room. How could the man tell if he was in : a village

The English name of an element is potassium, its Latin name will be :

The drawing shows a ship 800 m from a cliff. A gun is fixed on the ship. After 5 seconds the people at the front of the ship hear the sound of the gun again.

(a) What is the name of this effect ?
(b) What happens to the sound at the cliff ?
(c) How far does the sound travel in 5 seconds ?
(d) Calculate the speed of sound.

The scientist who proposed the first letter (or first letter and another letter) of the Latin or English name of
an element as its symbol, was :

The atoms of which of the following pair of elements are most likely to exist in free state ?

The speed of highly penetrating ultrasonic waves is :

The symbols of the elements cobalt, aluminium, helium and sodium respectively written by a student are as
follows. Which symbol is the correct one ?

The atomic number of an element X is 13. What will be the number of electrons in its ion X3+ ?

The anion of an element has ______.

An element which can exhibit valencies of 2, 4 and 6 can be :

Two elements X and Y have valencies of 5 and 3, and 3 and 2, respectively. The elements X and Y are most likely to be respectively :

The formula of the sulphate of an element X is X2(SO4)3. The formula of nitride of element X will be :