Explanation:
Bond forming:
Given species:
Na - Sodium Cl - Chlorine
Na has a valence electron
Cl has 7 valence electron
To form a bond of this nature, there must be a transfer of electrons.
Here, the bond is between a metal and non-metal
The metal is sodium and the non-metal is chlorine;
Na → Na⁺ + e⁻ loss of 1 electron
2,8,1 2,8
isoelectronic with Neon
Cl + e → Cl⁻ gain of one electron
isoelectronic with Argon
Na⁺ + Cl⁻ → Na⁺.Cl⁻
This bond type is an ionic bond
Answer:

Explanation:
Hello,
In this case, it is possible to determine the pressures of both helium and neon as shown below:

Now, one considers the total moles (addition between both neon's and helium's moles) and the total volume to compute the final pressure as shown below:

Best regards.
Its true it affects the pH balance
The amount of sample that is left after a certain period of time, given the half-life, h, can be calculated through the equation.
A(t) = A(o) (1/2)^(t/d)
where t is the certain period of time. Substituting the known values,
A(t) = (20 mg)(1/2)^(85.80/14.30)
Solving,
A(t) = 0.3125 mg
Hence, the answer is 0.3125 mg.
I believe the answer I’d D
Hope it helps