Coal is not a mineral. It's not a mineral because minerals are inorganic. Coal is organic because it comes from decayed living matter.
You will need the equation PV = nRT
P = Pressure in kPa
V = Volume in L
n = moles
R = 8.314 (constant)
T = Temperature in Kelvin
First convert 2.5 atm into kPa:
2.5 X 101.3 = 253.25 kPa
Convert 125 Celsius into Kelvin:
125 + 273 = 398 K
Convert Gallons to Litres:
1.25 X 3.79 = 4.74 L
Plug your values into the equation to solve for n:
(253.25)(4.74) = n(8.314)(398)
n = (253.25)(4.74)/(8.314)(398)
n = 0.362 moles
Now use M = m/n to solve for the mass of O2
M = Molar Mass
M = mass
n= moles
32 = m/(0.362)
m = (32)(0.362)
m = 11.58g
Answer:
OMG so big question!!!!!!!!!!!!
Answer: There are 0.000043 moles of melatonin.
Explanation:
According to avogadro's law, 1 mole of every substance occupies 22.4 L at STP and contains avogadro's number
of particles.
To calculate the moles, we use the equation:

given mass = 10 mg = 0.01 g
molar mass of
= 232.28 g
Thus there are 0.000043 moles of melatonin
Answer : The mole fraction of NaCl in a mixture is, 0.360
Explanation : Given,
Moles of
= 7.21 mole
Moles of
= 9.37 mole
Moles of
= 3.42 mole
Now we have to calculate the mole fraction of
.

Now put all the given values in this formula, we get:

Therefore, the mole fraction of NaCl in a mixture is, 0.360