N-14 NMR

How can 14^N be NMR active if it has 7 N and 7 Protons? I understood the text as both must be even numbers for the nucleus to be active (TA). (Not quite. If the number of neutrons and protons is odd, the nucleus is always magnetic, because the magnetic moments of individual nuclei can not compensate for each other. If this number is even, they usually do, and the nucleus is not magnetic. Sometimes, the magnetic moments of nuclei are aligned (two nuclei have the same magnetic moments, instead of the opposite moments), and then the nucleus is magnetic. 14N is an example (so-called quadrupole nucleus). Another simpler example is deuterium (2H) - GS. 

Why are SN2 reactions better in aprotic? (Poor solvation of the nucleophile favors SN2, while poor solvation of the leaving group disfavors SN1. - GS). Are both Sn2 and Sn1 reactions better in polar vs nonpolar? (Yes. Polarity helps formation of a carbocation (for SN1) and helps to dissolve the nucleophile (for both SN2 and SN1). - GS).

Can we please re-discuss why protic solvents cause products to form faster and why they are more favored than aprotic solvents in SN1 reactions? (Because protic solvents solvate anions in addition to carbocations. - GS).

Can you explain conformation vs configuration?  (Configuration can be changed only by breaking chemical bonds. Conformation changes when a molecule adopts a different shape, without breaking bonds. - GS). So E/Z would be considered a configuration? (Yes. - GS). Okay, thanks!

What is the difference between NaNh2 and Na, NH3 (This first reagent is a strong base, the second one is a strong reducing agent. - GS).

Why does halogenation of alkynes make stereoselectivity of addition unpredictable? (Because the 3-membered bromonium responsible for anti-stereoselectivity, is unstable (too strained) - GS).

What are other ways to create an acetylenide other than using NaNH2? (Grignard reagents, alkyllithium compounds, such as Butyl lithium - GS).