<span>1. Which variable is the independent variable and which is the dependent variable? Density vs. ethylene glycol
The independent variable would be ethylene glycol and dependent variable would be density.
A. A 25-mL volumetric flask with its stopper has a mass of 32.6341 g. The same flask filled to the line with ethylene glycol (C2H6O2, automotive antifreeze) solution has a mass of 58.0091 g. What is the density of the ethylene glycol solution?
Density = 58.0091 - 32.6341 / .025 = 1015 g/L
B. What is the molarity of the ethylene glycol solution, if the mass of ethylene glycol in the solution is 12.0439 g?
Molarity = 12.0439 ( 1 mol / 62.07 g) / 0.025 = 7.8 M</span>
Answer:

Explanation:
Hello,
In this case, since the rms speed of the molecules is computed by:

Whereas the absolute temperature is computed from the internal energy (by using the Cp of helium (3.1156 J/g*K) as shown below:

Thereby, the rms speed results:

Regards.
Answer: 1.09 g
Explanation:
If we use the approximation that 1 mole is 22.4 L, then setting up a proportion,
- 1/22.4 = x/0.345 (x is the number of moles in the sample)
- x = 0.0154 mol
Since the mass of a mole of chlroine is about 70.9 g/mol, (0.0154)(70.9) = 1.09 g (to 3 s.f.)