Answer:
Nitrogen has 5 valence electrons
Explanation:
nitrogen has it's attoms form triple bonds which are very hard to break
so non-reactive
I would have to say it would be the closest to a gas A.
Sound energy is produced when an object vibrates. The sound vibrations cause waves of pressure that travel through a medium, such as air, water, wood or metal. Sound energy is a form of mechanical energy. (I believe this is it)
Answer:
0.0177 L of nitrogen will be produced
Explanation:
The decomposition reaction of sodium azide will be:

As per the balanced equation two moles of sodium azide will give three moles of nitrogen gas
The molecular weight of sodium azide = 65 g/mol
The mass of sodium azide used = 100 g
The moles of sodium azide used = 
so 1.54 moles of sodium azide will give =
mol
the volume will be calculated using ideal gas equation
PV=nRT
Where
P = Pressure = 1.00 atm
V = ?
n = moles = 2.31 mol
R = 0.0821 L atm / mol K
T = 25 °C = 298.15 K
Volume = 
Group 1 elements (usually called alkali metals) are not very electronegative and have small ionization energies due to that. The reason why they are not very electronegative is that they really want to loose their one valence electron so that they can have a noble gas electron configuration (completed octet).
I hope this helps.