Answer:
1. Proton number is 9
2. Neutron number is 10
3. Electron number is 9
Explanation:
The following data were obtained from the question:
Atomic number = 9
Mass number = 19
1. Determination of the number of protons.
The atomic number of an element is simply the number of protons present in the atom of that element. Mathematically, it is expressed as:
Atomic number = proton number
Atomic number = 9
Proton number = atomic number = 9
Thus, the proton number is 9
2. Determination of the Neutron number.
Mass number = 19
Proton number = 9
Neutron number =?
Mass number = Proton + Neutron
19 = 9 + Neutron
Collect like terms
19 – 9 = Neutron
10 = Neutron
Thus, the Neutron number is 10.
3. Determination of the number of electrons.
Since the sample is made up of neutral atoms, the number of protons and electrons are equal i.e
Electron number = Proton number
Proton number = 9
Electron number = Proton number = 9
Thus, electron number is 9