For the reaction 2 K + F2 --> 2 KF,
consider K atomic wt. = 39
23.5 g of K = 0.603 moles, hence following the molar ratio of the balanced equation, 0.603 moles of potassium will use 0.3015 moles of F2. (number of moles, n = 0.3015)
Now, following the ideal gas equation, PV = nRT
P = 0.98 atm
V = unknown
n = 0.3015 moles
R = 82.057 cm^3 atm K^-1mole^-1 (unit of R chosen to match the units of other parameters; see the reference below)
T = 298 K
Solving for V,
V = (nRT)/P = (0.3015 mol * 82.057 cm^3 atm K^-1 mol^-1 * 298 K)/(0.98 atm)
solve it to get 7517.6 cm^3 as the volume of F2 = 7.5176 liters of F2 gas is needed.
2. Use the formula: volume1 * concentration 1 = volume 2 * concentration 2
where, volume 1 and concentration 1 are for solution 1 and volume 2 and solution 2 for solution 2.
Solution 1 = 12.3 M NaOH solution
Solution 2 = 1.2 M NaOH solution
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Solving for volume 1, volume 1 = (12.4 L * 1.2 M)/12.3 M = 0.1366 L </span>
Helium can be liquefy through a very
low temperature because of the weakness of attractions between the helium
atoms. In addition, helium is a noble gas that has a very weak interatomic London
dispersion forces. Thus, this element would remain liquid at atmospheric pressure
all the way to its liquefaction point going to absolute zero.
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Well it's definitely not visible or thermal, so it's <u>electromagnetic waves</u><u>.</u>
The solutions vapor pressure would be lower.
