# Chemistry

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I have just moved and transferred to a new school. My chemistry class is really ahead of my old class, so I am having some problems that I just cannot understand through the book. I guess I could ask the teacher but I am a bit shy and this assignment is due Tuesday anyway. We are doing the gas laws and it is temperature-volume that I really cannot understand. If someone could show me how to do some of these problems it would help me. Just please don't give me the answers only because it will not help me on the upcoming test.. (Eeek!)

1. What would happen to a balloon's volume, originally at 20 degrees C, if you took the balloon outdoors in a temperature of 40 degrees C? Assume that the pressure is constant and the balloon does not allow any gas to escape.

2. In planning to administer a gaseous anesthetic to a patient,
a. Why must the anesthesiologist take into account the fact that during surgery the gaseous anesthetic is used both at room (18 degrees C) and the patient's body temperature (37 degrees C)?
b. What problems might arise if the anesthesiologist did not allow for the patient's higher body temperature?

3. An air bubble trapped in bread dough at room temperature (291K) has a volume of 1.0 mL. The bread bakes in the oven at 623K (350 degrees C):
a.Predict whether the air-bubble volume will increase or decrease as the bread bakes. Explain using the kinetic molecular theory.
b. Calculate the new volume of the air-bubble, using Charles' law.

4. You buy a 3.0-L helium balloon in a mall and place it in a car sitting in the summer sunlight. The temperature in the air-conditioned mall is 22 degrees C and the temperature in the the closed car is 45 degrees C
a. What will you observe happening to the balloon as it sits in the warm car?
b. What will be the new volume of the balloon?

If someone could help me out I would be really grateful. I noticed some of these questions looked alike so there must be something I could learn to be able to do it. It also might help if I actually knew what the kinetic molecular theory was..

• Chemistry - ,

Not all of these problems are work alike. It would have helped if you had told us what you didn't understand about them. In general, T goes up, V goes up. T goes down, V goes down. Remember this general equation.
(P1V1)/T1 = (P2V2)/T2
If its a Pressure, temperature problem, jut cross V1 and V2 out and work from there. If it's a pressure volume problem, just cross out T and work from there. ETC. Remember T is in Kelvin.
For problem 1.

1. What would happen to a balloon's volume, originally at 20 degrees C, if you took the balloon outdoors in a temperature of 40 degrees C? Assume that the pressure is constant and the balloon does not allow any gas to escape.

The problem isn't asking you to calculate anything. T was 20 and you take the balloon outside where it is 40. So T goes up, Volume goes up. So the answer is that the volume will increase.

• Chemistry - ,

3. An air bubble trapped in bread dough at room temperature (291K) has a volume of 1.0 mL. The bread bakes in the oven at 623K (350 degrees C):
a.Predict whether the air-bubble volume will increase or decrease as the bread bakes. Explain using the kinetic molecular theory.
KMT generally says that higher temperature causes the molecules/atoms to move faster which gives them more energy and they exert more pressure which will require that the air bubble become larger. I suggest you read in yur book about KMT. I can't type all that material here.

b. Calculate the new volume of the air-bubble, using Charles' law.
In my first post I said
(P1V1)/T1 = (P2V2)/T2. Notice that the pressure is constant; therefore, we just drop the P1 and P2 to arrive at
V1/T1 = V2/T2 and that is Charles' Law.
V1 = 1.0 mL
T1 = 291K
V2 = ?? solve for this
T2 = 623 K.
Solve for V2. I went through it and I have an answer of 2.14 which I would round to 2.1 mL.

This should get you started. Post again if you still have trouble but show us your work and/OR tell us exactly what you don't understand about the problem.
Also, I suggest one problem per post.

• Chemistry - ,

2. In planning to administer a gaseous anesthetic to a patient,
a. Why must the anesthesiologist take into account the fact that during surgery the gaseous anesthetic is used both at room (18 degrees C) and the patient's body temperature (37 degrees C)?
b. What problems might arise if the anesthesiologist did not allow for the patient's higher body temperature?

a.) Core temperature monitoring is used to monitor intraoperative hypothermia, prevent overheating, and facilitate detection of malignant hyperthermia.