Advertisements
Advertisements
प्रश्न
State two observations which show that atom is not indivisible.
Advertisements
उत्तर
Two observations, which show that an atom is divisible are-
(1) Discharge-tube experiment : In J. J. Thomson's experiment, the stream of cathode rays in the gas-discharge tube shows the presence of negatively charged subatomic particles called electrons.
(2) In Goldstein's experiment, the faint red glow in the gas discharge tube shows the presence of positively charged subatomic particles called protons.
These experiments show that atoms are divisible and made up of subatomic particles, electrons, protons and neutrons.
APPEARS IN
संबंधित प्रश्न
Why is it not possible to see an atom with naked eyes?
If bromine atom is available in the form of, say, two isotopes `""_35^79Br (49.7%)" and """_35^81Br (50.3%)`, calculate the average atomic mass of bromine atom.
WRITE SHORT ANSWER
What is radioactivity?
Define: Ions
Name the particles which revolve around the nucleus.
Who originated the word ‘atom’ ?
An atom has 13 protons and 14 neutrons.
What is the atomic number of the atom ?
Fill in the blank
An _______ is electrically neutral.
Fill in the blank
An excess of electrons produces a ________ charge.
Fill in the following blanks with suitable words :
In water, the proportion of oxygen and hydrogen is .............. by mass.
Elements X and Y have 1 and 7 electrons in their outermost shell respectively.
Which will form positive ion?
Elements X and Y have 1 and 7 electrons in their outermost shell respectively.
What will be the charge present of the molecule XY after chemical combination?
Draw the basic structure of an atom representing its –
- Subatomic particles
- Nucleus
- Orbits or shells.
Select the correct answer to the statement given below:
The basic unit of matter is not capable of independent existence.
A compound containing one atom of carbon and two atoms of oxygen is ______.
______ is the smallest particle of an element.
A change in the physical state can be brought about
The graphite refill used is pencil is made of element called ______.
Atoms have a radius of the order ______.
