Atomic Basic Structure

The atomic number of an element is

• no of protons in the nucleus

• no of neutrons in the nucleus

• no of protons plus neutrons

• no pf protons minus neutrons

The mass number of an element is

• no of protons in the nucleus

• no of electrons rotating around the nucleus

• no of protons plus no of neutrons

• no of neutrons in nucleus

The energy levels in which electrons rotate are called

• L,M,N,O

• A,B,C,D

• K,L,M,N

• J,K,L,M

If the number of electrons in the outermost energy level is 8, the atom is considered stable (inactive)

• True

• False

Chemical symbol of Sodium

Chemical symbol of Magnesium

Chemical symbol of Chlorine

The energy level L is said to be saturated by

• 2 electrons

• 8 electrons

• 18 electrons

• 32 electrons

Answer explanation

K takes 2

L takes 8

M takes 8 or 18

N takes 32

The atom is

• electrically neutral

• negatively charged

• positively charged

Answer explanation

The atom is electrically neutral because it has an equal amount of negatively charged electrons and positively charged protons.

Noble gases are

• active

• inert

• unstable