The answer is definitely D
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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Manipulation of the independent variable should change the dependent variable, the value of which "depends" on the independent variable's change in value.
Dilution refers to decreasing the ratio of total solution to the reference solution by the addition of other liquids. By adding water to tomato soup, the balance of “tomato soup” molecules decreases from 100% tomato soup, to eventually 1:1 TS and Water (50%), and so on. Chemically, you can observe this as decreasing the concentration of tomato soup in this solution.
Stationary Front: a front that is not moving. When a warm or cold front stops moving, it becomes a stationary front.