An aqueous solution is 1.33 molality in method determine the amount fraction of methenal and water
*shocks it's in MOLALITY. @_@ Please disregard the above post!
Molality is moles of solute per kilogram solvent. Thus we can say there are 1.33 moles of CH2O in 1000 g of H2O.
To get the moles of H2O, we divide the mass (1000 grams H2O) by its molar mass.
molar mass of H2O = 2 + 16 = 18 g/mol
n, H2O = (1000 g) / 18 g/mol
n, H2O = 55.56 mol H2O
We can therefore get the mole fractions:
x, CH2O = 1.33 / (1.33 + 55.56)
x, CH2O = 0.0238
x, H2O = 1 - 0.0238
x, H2O = 0.9762
Sorry about that. lol the solution was way shorter compared to the previous.
By the way, I'm not sure if you really meant "methanal" or "methanol" (CH3OH). But either way, the value of the mole fractions are the same. (But of course, if it's molarity, they won't be the same)
Hope this helps~ ;)
Methanal is also formaldehyde, which has a chemical formula of HCHO (or CH2O).
Molarity is moles of solute per liter of solution. Thus we can say there are 1.33 moles of CH2O in 1 L of solution.
To get the mole fraction, we also need to get the moles of H2O. To do this, we get the volume of 1.33 mol CH2O from the moles by multiplying moles by its molar mass, and then dividing it by its density. From references, at normal conditions, the density of CH2O = 0.8153 g/mL.
molar mass of CH2O = 12 + 2 + 16 = 30 g/mol
V, CH2O = 1.33 mol (30 g/mol) / 0.8153 g/mL
V, CH2O = 48.939 mL CH2O
V, H2O = 1000 mL - 48.939 mL
V, H2O = 951.061 mL
Then we get the moles of H2O from the volume by multiplying it by the density and then dividing it by the molar mass. From references, at normal conditions, density of H2O = 1 g/mL
molar mass of H2O = 2 + 16 = 18 g/mol
n, H2O = (951.061 mL)(1 g/mL) / 18 g/mol
n, H2O = 52.837 mol H2O
We can therefore get the mole fractions:
x, CH2O = 1.33 / (1.33 + 52.837)
x, CH2O = 0.0246
x, H2O = 1 - 0.0246
x, H2O = 0.975
Hope this helps~ :)
To determine the amount fraction of methanol and water in an aqueous solution, you need to know the mole fraction of each component. Mole fraction is the ratio of the number of moles of a specific component to the total number of moles in the solution.
In this case, let's say we have an aqueous solution that is 1.33 molality in methanol. Molality (m) is defined as the number of moles of solute (methanol) divided by the mass of the solvent (water) in kilograms.
First, we need to determine the number of moles of methanol in the solution. The molality (m) is given as 1.33 molality, which means there are 1.33 moles of methanol per kilogram of water. We also need to know the molecular weight of methanol, which is approximately 32.04 g/mol.
To convert the given molality into moles of methanol, we can use the following formula:
moles of methanol = molality x mass of water (in kg)
Since we are not given the mass of water, we need another piece of information to proceed. For example, if we are given that the total mass of the solution is 1000 grams, we can assume that the mass of water is 1000 - mass of methanol.
Once we have the number of moles of methanol, we can determine the mole fraction of methanol using the following formula:
mole fraction of methanol = moles of methanol / total moles in the solution
To find the amount fraction, we can convert the mole fraction to the amount fraction using the following relationship:
amount fraction = mole fraction x molecular weight of the component / molecular weight of the mixture
Similarly, we can find the amount fraction of water using the mole fraction of water.
It's essential to note that without additional information, such as the total mass of the solution or the mass of water, we cannot precisely determine the amount fraction of methanol and water in the given aqueous solution.