ApasScript.

Solutions

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raoult Apas Cloud

Raoult's law for a binary liquid mixture of volatile A and B: the partial pressures `pA` = x_A p°_A and `pB`, the `total`, the liquid fractions `xA`, `xB` and the vapour's `yA`, `yB` (Dalton). Pressures in the unit of p°.

raoultFromVapour Apas Cloud

The liquid in equilibrium with a vapour of mole fraction y_A (the same record as `raoult`).

raoultFromTotal Apas Cloud

The liquid whose total vapour pressure is p (between p°_B and p°_A; the same record as `raoult`).

henry Apas Cloud

Henry's law p = K_H x: the partial pressure of a gas over a solution in which its mole fraction is x.

henryFraction Apas Cloud

Henry's law the other way: the mole fraction x = p/K_H dissolved under a partial pressure p.

henryConstant Apas Cloud

Henry's constant K_H = p/x from one measurement.

azeotrope Apas Cloud

The azeotrope of a non-ideal mixture in the one-parameter (Margules) model p_A = x_A p°_A exp(A x_B²), p_B = x_B p°_B exp(A x_A²): the composition where the vapour has the liquid's composition (the record of `raoult`), or the word none. A > 0 is a positive deviation (a minimum-boiling azeotrope), A < 0 negative.

relativeLowering Apas Cloud

The relative lowering of vapour pressure (p° − p)/p°, equal to the solute's mole fraction.

solutionPressure Apas Cloud

The vapour pressure of a solution of a non-volatile solute: p = p° n₁/(n₁ + i n₂).

molarMassFromLowering Apas Cloud

The molar mass of a solute from the relative lowering: exact from x₂ = n₂/(n₁ + n₂), or with the word dilute NCERT's x₂ ≈ n₂/n₁ (Ex 1.8).

molalityOf Apas Cloud

The molality in mol/kg of w₂ g of a solute of molar mass M₂ in w₁ g of solvent.

boilingElevation Apas Cloud

The elevation of the boiling point ΔT_b = i K_b m.

freezingDepression Apas Cloud

The depression of the freezing point ΔT_f = i K_f m.

molarMassFromDeltaT Apas Cloud

The molar mass of a solute from an elevation or a depression: M₂ = i K w₂ 1000/(ΔT w₁), in g/mol.

osmoticPressure Apas Cloud

The osmotic pressure π = i C R T in atm (R = 0.0821 L atm/K/mol), or in bar with the word bar (R = 0.083 as NCERT uses).

molarMassFromOsmotic Apas Cloud

The molar mass from the osmotic pressure of w g of solute in V litres at T: M = i w R T/(π V), π in atm or (with the word bar) in bar.

isotonic Apas Cloud

The concentration in mol/L that is isotonic with (has the same osmotic pressure as) a solution of osmotic pressure π at T.

vantHoff Apas Cloud

The van't Hoff factor i = observed colligative property / calculated, or calculated molar mass / observed molar mass.

dissociationDegree Apas Cloud

The degree of dissociation α = (i − 1)/(n − 1) of a solute that gives n particles.

associationDegree Apas Cloud

The degree of association α = (1 − i) n/(n − 1) of a solute that forms n-mers.

factorFromDissociation Apas Cloud

i = 1 + (n − 1) α for a degree of dissociation α into n particles.

factorFromAssociation Apas Cloud

i = 1 − α (1 − 1/n) for a degree of association α into n-mers.

ebullioscopicConstant Apas Cloud

K_b = R T_b² M/(1000 ΔH_vap) in K kg/mol.

cryoscopicConstant Apas Cloud

K_f = R T_f² M/(1000 ΔH_fus) in K kg/mol.

solvent Apas Cloud

A solvent of NCERT XII Table 1.3: `bp` and `fp` in K, `Kb` and `Kf` in K kg/mol, `M` in g/mol. Water, ethanol, cyclohexane, benzene, chloroform, carbon tetrachloride (CCl4), carbon disulphide (CS2), diethyl ether, acetic acid.

raoultOn Apas Cloud

Draws Raoult's law on a diagram: p_A, p_B and p = p_A + p_B against x_A (pure B at the left, pure A at the right). With "positive", "negative" or a Margules parameter A the observed curves are drawn over the dashed ideal lines and the azeotrope is marked; a final x_A marks that composition with its pressures in the caption.

henryOn Apas Cloud

Draws Henry's law on a diagram: the partial pressure of a gas against its mole fraction in the solution, a line of slope K_H.

colligativeOn Apas Cloud

Draws the vapour-pressure curves of a solvent and its solution against temperature: "boiling" shows the solution reaching 1 atm later (ΔT_b), "freezing" the solid's curve met earlier (ΔT_f), "both" the two ends. Not to scale: the gaps are drawn large; the caption gives the real ΔT_b and ΔT_f of the solvent (water unless named) at the molality (1 mol/kg unless given).

osmosisOn Apas Cloud

Draws osmosis: a vessel parted by a semipermeable membrane, solvent at the left and solution at the right. "flow" the solvent passing in, "equilibrium" the solution's level higher by h, "pressure" the piston whose pressure π just stops the flow, "reverse" a pressure above π driving solvent out.