Answer:
5
Explanation:
A lithium atom with an atomic number of 3 and a charge of -2 will have a total number of electrons.
The atomic number is the number of protons in an atom. For a neutral atom that has not gained or lost electrons, the atomic number is the same as the number of electrons.
neutral atom: atomic number of electrons
For neutral atom of lithium, we will have 3 electrons
Now, lithium with a charge of -2 has gained two more electrons to the original 3 this now makes it 5.
ii.
It is an anion because it is negatively charged.
Negatively charged particles are called anion.
Given that the pressure, temperature and area of effusion is constant, the rate of effusion is inversely proportional to the square root of the molecular mass of the gas.
Mr Oxygen = 32
Mr Argon = 40
Effusion Oxygen = 1/√32
Effusion Argon = 1/√40
Effusion Oxygen / Effusion Argon = √(40) / √(32)
=√(40/32) = √(5/4) = 1.19
Thus, Oxygen will effuse 1.19 times faster than Argon. The second option is correct.
The subscript 2 indicate that there are two atoms of chlorine in the compound.
<u><em> Explanation</em></u>
Subscript in the chemical formula indicate the number of atoms of the element immediately before the subscript.
In MgCl₂ there are two(2) atoms of chlorine since Subscript 2 is immediately after chlorine.
Compounds are represented by chemical formulas