The answers are:
1. D
2. B if it is a check all that are true it is b & d
Solids are packed together closely, liquids are farther apart but still relatively close, and gases are very far apart with lots of space.
The equilibrium constant for the reaction is 0.00662
Explanation:
The balanced chemical equation is :
2NO2(g)⇌2NO(g)+O2(g
At t=t 1-2x ⇔ 2x + x moles
The ideal gas law equation will be used here
PV=nRT
here n=
=
= density
P =
density is 0.525g/L, temperature= 608.15 K, P = 0.750 atm
putting the values in reaction
0.75 = 
M = 34.61
to calculate the Kc
Kc=![\frac{ [NO] [O2]}{NO2}](https://tex.z-dn.net/?f=%5Cfrac%7B%20%5BNO%5D%20%5BO2%5D%7D%7BNO2%7D)
x M NO2 +
M NO+
M O2
Putting the values as molecular weight of NO2, NO,O2

34.61= 
x= 0.33
Kc= 
putting the values in the above equation
Kc = 0.00662