<u>Answer:</u>
<u>For A:</u> The
for the given reaction is 
<u>For B:</u> The
for the given reaction is 1642.
<u>Explanation:</u>
The given chemical reaction follows:

The expression of
for the above reaction follows:

We are given:

Putting values in above equation, we get:

Hence, the
for the given reaction is 
Relation of
with
is given by the formula:

where,
= equilibrium constant in terms of partial pressure = 
= equilibrium constant in terms of concentration = ?
R = Gas constant = 
T = temperature = 500 K
= change in number of moles of gas particles = 
Putting values in above equation, we get:

Hence, the
for the given reaction is 1642.
Answer: An igneous rock that cools rapidly is made of really small mineral crystals.
Explanation:
The layers inside the earth are hot enough to melt a rock. The liquid or molten rock is known as magma.
When a molten rock cools and solidifies, it results in the formation of an igneous rock.
The slow cooling of magma will result in the formation of an igneous rock with large crystals. Whereas, rapid cooling of lava will result in the formation of an igneous rock with small crystals.
Thus, it can be concluded that an igneous rock that cools rapidly is made of really small mineral crystals.
Answer:
it would be the second choice
Scoria
Explanation:
Scoria is a rock that is commonly made up of gas bubbles and minerals such as hornblende, muscovite, olivine, lucite and or plagioclase.
Scoria is an extrusive igneous rock with a lot of cavities and vesicles indicating gas bubbles.
- Scoria is product of basaltic magma.
- It has nearly the same composition as basalt since it originates from it.
- They silica deficient and very fine grained with holes in them.
- The holes shows channels by which trapped gases are forcefully ejected out.
- They are usually found associated with cindercone volcanoes.
learn more:
Volcanoes brainly.com/question/5055821
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