If the radius of a potassium atom 227 times 10^-7 mm, what is the radius in mu m
ID: 536968 • Letter: I
Question
If the radius of a potassium atom 227 times 10^-7 mm, what is the radius in mu m? A certain liquid has a density of 2.67 g/cm^3. 1340 g of this liquid would occupy a volume of how many Liters? A compound that is composed of only carbon and hydrogen contains 80.0% C and 20.0% H by mass. What is the empirical formula of the compound? The temperature of a 500, mL sample of gas increases from 150. K to 350. K What is the final volume of the sample of gas, if the pressure in the container is kept constant?Explanation / Answer
1. radius of K atom = 2.27 x 10^-7 mm
= 2.27 x 10^-7 x 1000 = 2.27 x 10^-4 um
2. density = mass/volume
So,
volume = 1340 g/2.67 g/cm^3 x 1000
= 0.502 L
3. moles C = 80/12 = 6.67 mol
moles H = 20/1 = 20 mol
divide by smallest factor
C = 6.67/6.67 = 1
H = 20.6.67 = 3
empirical formula = CH3
4. new volume = initial volume x new temperature/initial temperature
= 500 ml x 350/150
= 1166.67 ml