Structure Of An Antom Short Question With Answer: General Science Cadet College Test
Q.No.01: Define an atom. Give an example?
Ans: The smallest particle of the matter that cannot exist independently is called an atom.
Example: C, H, O etc.
Example: C, H, O etc.
Q.No.02: What is nucleus?
Ans: Nucleus is a central part of an atom. It consists of protons and neutrons.
Q.No.03: What is the difference between electron and proton?
Ans: Electron has a negative charge and moves around the nucleus.
Proton has a positive charge and is found inside the nucleus.
Proton has a positive charge and is found inside the nucleus.
Q.No.04: What are neutrons?
Ans: Neutrons are subatomic particles. It has no charge on it. It is present in the nucleus. The mass of a neutron is equal to protons.
Q.No.05: Why are atoms neutral particles?
Ans: An atom is a neutral particle because the electrons outside the nucleus and protons inside the nucleus are equal in number. So, total positive charge is balanced by total negative charge.
Q.No.06: Define atomic number?
Ans: The number of protons present in the nucleus of an atom is called atomic number. It is represented by Z.
Q.No.07: Define mass number?
Ans: The sum of protons and neutrons inside the nucleus is called mass number. It is represented by A.
Q.No.08: What is a shell?
Ans: The path of the movement of electrons around the nucleus are called shells. Shells are also called energy levels.
Q.No.09: How shells are labeled in an atom?
Ans: The shells are labeled as K, L, M, N …… where K is the first shell nearest to the nucleus, L is second shell and so on.
Q.No.10: Calculate number of electrons in L & M shell?
Ans: The number of electrons can be calculated by 2n² formula.
In L or shell number 2, no. of electrons = 2n² = 2(2)² = 8
In M or shell number 3, no. of electrons = 2n² = 2(3)² = 18
In L or shell number 2, no. of electrons = 2n² = 2(2)² = 8
In M or shell number 3, no. of electrons = 2n² = 2(3)² = 18
Q.No.11: Define valency and give an example?
Ans: The capacity of an atom to combine with another atom is called valency.
Example: Hydrogen shares one electron, so its valency is 1.
Example: Hydrogen shares one electron, so its valency is 1.
Q.No.12: Define Ion?
Ans: An atom with positive or negative charge is called ion.
Example: Sodium ion (Na⁺)
Example: Sodium ion (Na⁺)
Q.No.13: What is the difference between cation and anion?
Ans: Cation: A positive ion. It is formed when an atom loses electrons.
Anion: A negative ion. It is formed when an atom gains electrons.
Anion: A negative ion. It is formed when an atom gains electrons.
