Advertisements
Advertisements
Question
An atom of an element X may be written as `""_9^4"X"`
(a) What does the figure 9 indicate?
(b) What does the figure 4 indicate?
(c) What is the number of protons in atom X?
(d) What is the number of neutrons in atom X?
(e) What is the number of electrons in atom X?
(f) How many electrons are there in the outermost shell of an atom of element X?
(g) Write the symbol of ion formed by an atom of element X.
Solution
(a) Figure 9 indicates the mass number.
(b) Figure 4 indicates the atomic number.
(c) No. of protons in atom X = 4
(d) No. of neutrons in atom X = 9 – 4 = 5
(e) No. of electrons in atom X = 4
(f) Electrons in the outermost shell of an atom of element X = 2
(g) X2+
APPEARS IN
RELATED QUESTIONS
TRUE \ FALSE
Elements having a tendency to accept electrons are called metals
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:-
Ammonia
Define: Mass number
What does the word ‘atom’ mean?
An atom has 13 protons and 14 neutrons.
What is the atomic mass of the atom ?
Fill in the blank
A deficiency of electrons produces a ________ charge.
Give brief information of three subatomic particles with reference to electrical charge, mass and location.
The electron shell ______ is nearest to the nucleus.
Deduce from the datum provided.
| Datum | To deduce |
| \[\ce{_11^23Na}\] | Neutron number |
| \[\ce{_6^14C}\] | Mass number |
| \[\ce{_17^37 Cl}\] | Proton number |
Draw diagrams representing the atomic structures of the following:
- Sodium atom
- Chlorine ion
- Carbon atom
- Oxygen ion
Select the correct answer to the statement given below:
The basic unit of matter is not capable of independent existence.
The smallest particle of matter that can exist by itself is ______.
A compound containing one atom of carbon and two atoms of oxygen is ______.
Rewrite the given sentence in correct form.
Elements contain two or more kind of atoms and compounds contain only one kind of atom.
The smaller particles found in the atom is called ______.
Assertion: An atom is electrically neutral.
Reason: Atoms have equal number of protons and electrons.
Draw the structure of an atom and explain the position of the sub-atomic particles.
Atoms of different elements having the same number of ______ are called isotones.
The number of atoms present in a molecule is called its ______.
