Answer:
Molar mass of solute: 300g/mol
Explanation:
<em>Vapor pressure of pure benzene: 0.930 atm</em>
<em>Assuming you dissolve 10.0 g of the non-volatile solute in 78.11g of benzene and vapour pressure of solution was found to be 0.900atm</em>
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It is possible to answer this question based on Raoult's law that states vapor pressure of an ideal solution is equal to mole fraction of the solvent multiplied to pressure of pure solvent:
Moles in 78.11g of benzene are:
78.11g benzene × (1mol / 78.11g) = <em>1 mol benzene</em>
Now, mole fraction replacing in Raoult's law is:
0.900atm / 0.930atm = <em>0.9677 = moles solvent / total moles</em>.
As mole of solvent is 1:
0.9677× total moles = 1 mole benzene.
Total moles:
1.033 total moles. Moles of solute are:
1.033 moles - 1.000 moles = <em>0.0333 moles</em>.
As molar mass is the mass of a substance in 1 mole. Molar mass of the solute is:
10.0g / 0.033moles = <em>300g/mol</em>
Answer:
TLC is thin-layer chromatography, a chromatography technique which is used for separating the non-volatile mixtures.
Explanation:
To run a thin layer thin layer chromatography experiment with a chemical substance, begin by marking a horizontal line near the bottom of TLC plate with PENCIL. Place a SMALL spot of the substance onto the line. For the mobile phase add a small amount of SOLVENT at the bottom of TLC chamber. Place the plate in, then COVER the chamber. Once the mobile phase approaches the top of the plate, remove the plate and mark the SOLVENT line. Note the positions of the spot and calculate the Rf if needed.
Answer:
yes it can λ =265 nm
Explanation:
Here we will use the relationship
E = h c/λ ∴ λ = E/ hc where
h= Plank's constant
c= Speed of light
λ = Wavelength = ?
Substituting
note need E in J ,
E = 4.7 eV x 1.602 x 10⁻¹⁹ J/eV = 7.5 x 10⁻¹⁹ J)
λ = 7.5 x 10 ⁻¹⁹ J / ( 6.626 x 10⁻³⁴ Js x 3 x 10^8) = 2.65 x 10⁻⁷ m = 2.65
= 2.65 x 10⁻⁷ m x 1 x 10⁹ nm/m = 265 nm
