I know for number 4 the answer is c, sorry I can't help with the others.
Answer:
1120 L.
Explanation:
Hello!
In this case, as no conditions of pressure of temperature are given for this problem, we can assume that the scuba diver dives at STP (1 atm and 273.15 K), which means that 1 mole of air would occupy a volume of 22.4 L.
In such a way, since she needs 50.0 moles of air, the following ratio is useful to compute the size (volume) of the tank she needs:

Thereby, we plug in to obtain:

Best regards!
Answer:
295.7 mL of 24% trichloroacetic acid (tca) is needed .
Explanation:
Let the volume of 24% trichloroacetic acid solution be x
Volume of required 10% trichloroacetic acid solution =8 bottles of 3 ounces
= 24 ounces = 709.68 mL
(1 ounces = 29.57 mL)
Amount of trichloroacetic acid in 24% solution of x volume of solution will be equal to amount of trichloroacetic acid in 10% solution of volume 709.68 mL.

x = 295.7 mL
295.7 mL of 24% trichloroacetic acid (tca) is needed .
The formula we use would be the graham's law. We do as follows:
<span>E_Kr / E_Ne = sqrt ( M_Ne / M_Kr)
</span>
<span>= sqrt ( 20.1797 g/mol / 83.798 g/mol ) </span>
<span>= sqrt (0.24081) </span>
<span>= 0.4907
</span>
Hope this answers the question. Have a nice day.