atoms are made of 3 types of subatomic particles; electrons, protons and neutrons
atomic number is the number of protons. atomic number is characteristic for the element. In ground state atoms, the number of electrons and protons are the same.
the electronic configuration of Ca in the ground state is
Ca - 1s² 2s² 2p⁶ 3s² 3p⁶ 4s²
when Ca loses its 2 valence electrons, it becomes positively charged and the electronic configuration becomes
Ca - 1s² 2s² 2p⁶ 3s² 3p⁶
number of electrons in Ca²⁺ is 18
the atom in the ground state would have the same number of electrons and protons. Therefore number of protons are 18. then the atomic number of the element is 18
the atom having an atomic number of 18 is Ar.
the answer is 1) Ar
Answer:
Neutrons.
Explanation:
Isotopes can be defined as the atom of an element that has the same number of protons but different number of neutrons. This ultimately implies that, the isotopes of an element have the same atomic number (number of protons) but different atomic mass (number of nucleons).
The isotope of an element is denoted by 
Where; X is the symbol of the element.
A is the atomic mass or number of nucleons.
Z is the atomic number or number of protons.
<em>Therefore, the number of neutrons = A - Z</em>
<em>Isotopes of carbon differ with respect to the number of neutrons.</em>
<em>Basically, there are three (3) Isotopes of Carbon and these are;</em>
<em>1. Carbon-12: it has an atomic mass of 12 with 6 numbers of proton and neutron respectively. </em>
<em>2. Carbon-13: it has an atomic mass of 13 with 6 numbers of proton and 7 numbers of neutron. </em>
<em>3. Carbon-14: it has an atomic mass of 14 with 6 numbers of proton and 8 numbers of neutron. </em>
Answer:
Na₁₁ = 1s² 2s² 2p⁶ 3s¹
Explanation:
Sodium is present in group 1.
It is alkali metal.
It has one valence electron.
The atomic number of sodium is 11.
Its atomic mass is 23 amu.
The longhand notation of electronic configuration of sodium can be written as,
Na₁₁ = 1s² 2s² 2p⁶ 3s¹
The electronic configuration in shorthand notation( noble gas) would be written as,
Na₁₁ = [Ne] 3s¹
Sodium loses its one valence electron to complete the octet and get stable thus form +1 cation.
It react with halogen and form salt. Such as sodium chloride.
2Na + Cl₂ → 2NaCl
