Advertisements
Advertisements
प्रश्न
Why is it not possible to see an atom with naked eyes?
Advertisements
उत्तर
The size of an atom is so small that it is not possible to see it with the naked eye. Also, an element's atom does not exist independently (its atomic radius is of the order of 10-10 m).
APPEARS IN
संबंधित प्रश्न
MATCH THE COLUMNAS
| 1. Jpham Dalton | a. Neutrons |
| 2. Atom | b. Model of the atom |
| 3. Chadwick | c.The atomic theory of matter |
| 4. Rutherfrod | d. Positively charged |
| 5. Protons | e. Electricity neutral |
| 6. Nuclear fusion | f. Generator of electricity |
| 7.Gamma -rays | g. High penetrating power |
| h.Energy in sun |
ANSWER IN DETAIL
State the postulates of the Dalton’s atomic theory.
ANSWER IN DETAIL
Enlist the features of Bohr’s model of an atom. How did he correct the Rutherford’s model ?
Write the names of the elements present in the following compound.
Common salt
Define: Ions
Define: Mass number
A certain particle ‘X’ has 17 protons, 18 electrons and 20 neutrons.
What is such a particle called ?
A certain particle ‘X’ has 17 protons, 18 electrons and 20 neutrons.
What is the charge on the particle ?
Write the relation between nanometre and metre.
State two observations which show that atom is not indivisible.
Which has more atoms, 50 g of aluminium or 50 g of iron ? Illustrate your answer with the help of calculations.
(Atomic masses : Al = 27 u ; Fe = 25 u)
Electron, proton, neutron are the types of ______ in an atom.
In what respects do the three isotopes of hydrogen differ? Give their structures.
Select the correct answer to the statement given below:
The basic unit of matter is not capable of independent existence.
Select the correct answer to the statement given below:
The smallest particle of a substance – capable of independent existence and which retains the characteristics of the substance.
The basic unit of matter is ______.
Dalton’s atomic theory successfully explained
(i) Law of conservation of mass
(ii) Law of constant composition
(iii) Law of radioactivity
(iv) Law of multiple proportions
______ is a substance that is made up of three oxygen atoms chemically combined.
What is the fundamental particle of an element?
The first scientific theory about atoms was given by J J. Thomson.
