The answer is D. (2,2,2,1)
Answer:
Once ignited, a ribbon of magnesium metal burns freely in air to form solid magnesium oxide in the form of a white powder. The reaction is plainly spontaneous even though ΔS is negative.
Answer:
C.
Explanation:
Exothermic means the energy of products is lower than energy of reactants. Transition state will always be the highest energy among the two.
Answer:
Vibrate?
Explanation:
In a solid the strong attractions between the particles hold them tightly packed together. Even though they are vibrating this is not enough to disrupt the structure. When a solid is heated the particles gain energy and start to vibrate faster and faster.
Explanation:
For AX type ceramic material, the number of formula per unit cells is as follows.

or, 
where, n' = no. of formula units per cell
= molecular weight of cation = 90.5 g/mol
= molecular weight of anion = 37.3 g/mol
= volume of cubic cell = 3.55
a = edge length of unit cell = 
= Avogadro's number = 
= density = 3.55 
Now, putting the given values into the above formula as follows.

= 
= 0.9
= 1 (approx)
Therefore, we can conclude that out of the given options crystal structure of cesium chloride is possible for this material.