Answer:
B They move because of the convection currents in the mantle.
Answer:
b. 1.5 atm.
Explanation:
Hello!
In this case, since the undergoing chemical reaction suggests that two moles of A react with one moles of B to produce two moles of C, for the final pressure we can write:

Now, if we introduce the stoichiometry, and the change in the pressure
we can write:

Nevertheless, since the reaction goes to completion, all A is consumed and there is a leftover of B, and that consumed A is:

Thus, the final pressure is:

Therefore the answer is b. 1.5 atm.
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1. 6 carbon atoms and triple bonding between carbons 2 and 3
2. i think it’s 3 but i may be wrong
Substance a is a base, and substance b is an acid