Carcass wrote:
For a certain quantity of a gas, pressure P, volume V, and temperature T are related according to the formula PV = kT, where k is a constant.
Quantity A |
Quantity B |
The value of P if V = 20 and T = 32 |
The value of T if V = 10 and P = 78 |
QUANTITY A: The value of P if V = 20 and T = 32Take given formula, PV = kT, and plug in values to get: P(20) = k(32)
Divide both sides by 20 to get: P = 32k/20
Simplify to get: P = 8k/5
QUANTITY B: The value of T if V = 10 and P = 78Take given formula, PV = kT, and plug in values to get: (78)(10) = kT
Divide both sides by k to get: (78)(10)/k = T
Simplify to get: T = 780/k
So, we have:
QUANTITY A: 8k/5
QUANTITY B:780/kLet's TEST some possible values of kTry k =
1In this case, we get:
QUANTITY A: 8k/5 = (8)(
1)/5 = 8/5
QUANTITY B:780/k = 780/
1 = 780
In this case, QUANTITY B IS GREATER
Try k =
1000In this case, we get:
QUANTITY A: 8k/5 = (8)(
1000)/5 = some number greater than 1
QUANTITY B:780/k = 780/
1000 = some number less than 1
In this case, QUANTITY A IS GREATER
Answer: D
Cheers,
Brent
_________________
Brent Hanneson – Creator of greenlighttestprep.com
Sign up for my free GRE Question of the Day emails