A sample of gas at a temperature of 37.0°C has a pressure of 725 torr and occupies a volume of 3.44 L.
a. Use Boyle’s law to calculate the new pressure if the temperature is held constant and the volume is increased to 6.54 L.
torr
b. Use Gay-Lussac’s law to calculate the new pressure if the volume is held constant and the temperature is decreased to 6.00°C.
torr
c. Use Charles’ law to calculate the new volume if the pressure is held constant and the temperature is increased to 210°C.
L
d. Use the combined gas law to calculate the new pressure if the temperature is decreased to 25.0°C and the volume is increased to 16.9 L.
torr
e. Use the ideal gas law to calculate the number of moles of gas that are present.
Moles
A= p1v1=p2v2
725(3.44)=?(6.54) = 381.45
B. p1t1=p2/t2
725(6.00)/37.0. = 117.567
C= v1t1=v2t2
3.44(210)/37.0= 19.524
D= p1v1t1=p2v2t2
725*3.44/37.0=?(16.9)/25.0 = 45.566
E..?
I keep getting b,c,d,e wrong but I don't know what I'm doing wrong
2 errors on B
1. should be p1/t1 = p2/t2
2. T must be in kelvin and you used C
3. Ans is about 652.
(725/310) = (p2/279)
C.wrong formula.
v1/t1 = v2/t2
(3.44/310) = v2/210)
Ans is approx 2.3 L
d.formula is (p1v1/t1) = (p2v2/t2)
(725*3.44/310) = p2*16.9/298).
Ans is approx 142.
e. PV = nRT
725*3.44 = n*0.0821*310
Solve for n.
Let's go through each problem step by step to identify the errors:
a. Use Boyle's law to calculate the new pressure if the temperature is held constant and the volume is increased to 6.54 L.
The formula for Boyle's law is P1V1 = P2V2. You correctly substituted the values into the formula to get 725 * 3.44 = P2 * 6.54. However, the result you obtained (381.45) is incorrect.
To solve for P2, you need to rearrange the formula:
P2 = (P1V1) / V2
Plugging in the values, we get:
P2 = (725 * 3.44) / 6.54
P2 ≈ 382.10 torr (rounded to two decimal places)
So the correct answer is approximately 382.10 torr.
Now let's move on to the other problems:
b. Use Gay-Lussac's law to calculate the new pressure if the volume is held constant and the temperature is decreased to 6.00°C.
You correctly used the formula p1t1 = p2t2. However, in your calculation, you divided by 37.0 instead of multiplying.
To solve for p2, you need to rearrange the formula:
p2 = (p1 * t2) / t1
Plugging in the values, we get:
p2 = (725 * 6.00) / 37.0
p2 ≈ 117.57 torr (rounded to two decimal places)
So the correct answer is approximately 117.57 torr.
c. Use Charles' law to calculate the new volume if the pressure is held constant and the temperature is increased to 210°C.
In your calculation, you incorrectly multiplied the initial volume instead of dividing.
The correct formula for Charles' law is V1 / T1 = V2 / T2.
Rearranging the formula, we get:
V2 = (V1 * T2) / T1
Plugging in the values, we get:
V2 = (3.44 * 210) / 37.0
V2 ≈ 19.57 L (rounded to two decimal places)
So the correct answer is approximately 19.57 L.
d. Use the combined gas law to calculate the new pressure if the temperature is decreased to 25.0°C and the volume is increased to 16.9 L.
In your calculation, you incorrectly multiplied the pressure by the volume instead of dividing.
The correct formula for the combined gas law is:
(P1 * V1) / T1 = (P2 * V2) / T2
Rearranging the formula, we get:
P2 = (P1 * V1 * T2) / (V2 * T1)
Plugging in the values, we get:
P2 = (725 * 3.44 * 298) / (16.9 * 273)
P2 ≈ 56.90 torr (rounded to two decimal places)
So the correct answer is approximately 56.90 torr.
e. Use the ideal gas law to calculate the number of moles of gas that are present.
The ideal gas law is given by the formula PV = nRT, where P is the pressure, V is the volume, n is the number of moles, R is the ideal gas constant, and T is the temperature in Kelvin.
To solve for the number of moles (n), we rearrange the formula:
n = (PV) / (RT)
Plugging in the values, we get:
n = (725 * 3.44) / (0.0821 * (37.0 + 273))
n ≈ 0.459 moles (rounded to three decimal places)
So the correct answer is approximately 0.459 moles.
I hope this helps clarify the errors in your calculations. Let me know if you have any further questions!