Class 9 Science: Structure of Atom Olympiad Questions

The atoms are the building blocks of matter. These are the smallest units of matter made of subatomic particles, such as neutrons, protons, and electrons.

The electrons are negatively charged atoms. And their mass is considered negligible, or we can say that it is 1,i.e., Negative. When we see the electron symbol, then it is negative,i.e., e-.

Valency

• The valency is the part of the outermost shell present in the atoms.
• The valency is the combining capacity of the atoms that will do their reaction to get the molecules with the same or different elements.
• The elements consist of the outermost shell that is full of chemical activities.
• And when we see their combined capacity, it is equal to zero.

Atomic number

• The atomic number refers to the total number of protons present in the atom's nucleus.
• The letter ' Z represents the symbol of the atomic number.'

Bohr's model

• Bohr's model states that atoms consist of a positive charge in the electrons and nucleus.
• And these will revolve around circular orbits with constant radii and energy.

Rutherford's model

• He states that the electricals are the neutral parts that contain a positive charge.