The volume ( Z ) of a gas varies directly as the absolute temperature ( Q ) and inversely as the pressure ( D ). Translate the statement of variation into an equation and use k as the constant of variation.
A) $Z = \frac { k Q } { D }$
B) $Z = k Q D$
C) $z = \frac { Q } { D }$
D) $Z = \frac { D } { Q }$
E) $z = \frac { k D } { Q }$

Question

Quizplus · Accepted Answer

The statement of variation can be written as:
Z ∝ Q (when pressure D is constant)
Z ∝ 1/D (when temperature Q is constant)

Combining these two variations, we get:
Z ∝ Q/D

Introducing a constant of proportionality k we get:
Z = kQ/D

So, the correct equation of variation is Z = kQ/D, which is given by choice A.

The Volume ( Z ) of a Gas Varies Directly Z=kQDZ = \frac { k Q } { D }Z=DkQ​

The Volume ( Z ) of a Gas Varies Directly $Z = \frac { k Q } { D }$