Answer:
Mg₁₂ = 1s² 2s² 2p⁶ 3s²
Explanation:
Abbreviated and unabbreviated electronic configuration:
The abbreviated electronic configuration uses the noble gas configuration i.e complete electronic shells. For example, the atomic number of neon is ten and magnesium is twelve. The abbreviated electronic configuration of magnesium is written by using the neon abbreviation in following way:
The electronic configuration of neon is given below:
Ne₁₀ = 1s² 2s² 2p⁶
The abbreviated electronic configuration of magnesium:
Mg₁₂ = [Ne] 3s²
While the unabbreviated electronic configuration is written without using noble gas electronic configuration.
Unabbreviated electronic configuration of magnesium:
Mg₁₂ = 1s² 2s² 2p⁶ 3s²
Through hypothesis and experiments
Answer:
The balanced molecular equation for the reaction :

Explanation:
The reaction between copper(II) nitrate and potassium carbonate gives solid precipitate of copper(II) carbonate and aqueous solution of potassium nitrate.

According to reaction, 1 mole of copper(II) nitrate reacts with 1 mole of potassium carbonate to give 1 mole of copper(II) carbonate and 2 moles of potassium nitrate,
1 mole of any substance contains Avogadro's number.
So, 1 mole of O2= 6.023x10^23 molecules
3 mole of O2= 6.023x10^23x3 molecules
= 1.8069x10^24 molecules
Each molecule of Oxygen has 2 atoms.
therefore,
1.8069x10^24 molecules= 1.8069x10^24 x 2 atoms
= 3.6138x10^24 atoms.
The answer is a.n=1 because it makes sence