Can anyone help me with my physical science questions?

Question

please include a percentage on how sure you are pleaseee

______ is the separation of ions in a solution.

A. Atomic Division

B. Dissection

C. Disconnection

D. Dissociation

Why are electrons NOT counted when calculating atomic mass?

A. They are on the outside of the nucleus.

B. They orbit the atom, so they aren’t actually a part of the atom.

C. They are generally so small, they don’t make enough of a difference.

D. They are a part of the neutrons in the atom, so they actually are counted.

Molecular shapes depend upon______.

A. how many atomic bonds can be formed

B. how many molecular bonds can be formed

C. how many ionic bonds can be formed

D. how many covalent bonds can be formed

Answer 1

1. Dissociation.

2. But, actually electrons ARE counted when determining the actual mass of an atom since atomic masses are often given to 5 or 6 decimal places.  

I think what you mean is the "mass number".  The mass number is the sum of the protons and neutrons in the nucleus.  

It's definitely not (D) or (B).  The masses of electrons are small compared to the masses of protons on neutrons, so one could think it is (C).  Or if the question is really talking about mass number, then the answer is definitely (A)

3. The shapes of molecules depend on the total number of electron pairs around the central atom which determines the electron pair geometry.  The actual shape of the molecule depends on the number of bonding pairs and the number of lone pairs.  Therefore, NONE of these are ACTUALLY correct.   But I think the (uniformed) writer of this question wants you to answer (D) since molecules typically contain covalent bonds.

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How sure am I?  I have an advanced degrees in chemistry and physics and I've taught chemistry for over 35 years.