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At very dilute concentrations, the solvating power of water overcomes the natural tendency of surfactant molecules to agglomerate into a separate phase. The shear numerical excess of water molecules just about totally dissociates the bulk surfactant and dissolves it as separate molecules. So a mixture of surfactant and water can be a true solution - clear ...

4

To understand why non - ideal mixtures form azeotropes, we need to understand what is ideal mixture. If you have a liquid mixture of two components A and B, ideal mixture is a mixture in which heterogeneous interactions (A - B) are the same as the average homogeneous (A - A and B - B). This means when you mix components A and B, they don't "feel" ...

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The point of the question is to test your understanding i. of Raoult's law (that increasing the solute concentration decreases the vapor pressure and that the identity of the solute is not important in an ideal solution; the mole fraction of solute determines $\Delta p$: $\Delta p = p-p^\circ = -\chi_\textrm{solute}p^\circ$ ii. that vapor pressure increases ...

3

It is not a messed up cycle. Let's consider what happens with an example. If you heat up a mixture containing $10$% ethanol + $90$% water, the mixture boils at $92$°C, producing a vapor containing $50$% ethanol + $50$% water. With this operation the liquid loses more ethanol than water. So its concentration in ethanol decreases, and it is necessary to heat ...

2

The starting point to solve the problem is Raoult's law. For each component we can write that the vapour pressure (related by Dalton's law to the total pressure) is equal to the product of the mole fraction in the solution and the vapour pressure of the pure component: $$y_iP_S = \chi _i P^{\circ} _i$$ You can exploit the fact that the molar amounts in the ...

1

You are correct. The net ionic reaction between zinc metal and Nitric acid can be written: $$\ce{Zn + 2 H+(aq) <=> Zn^2+(aq) + H2(g)}$$ The oxidation for Zinc changes as it is oxidized from a state of 2+ to 0. Similarly, Hydrogen's state changes as it reduces from 1+ to 0.

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Before dissolution, the substance is usually a solid and forms crystals. Its physical state is solid. After dissolution, the substance is not visible any more : it is not a solid any more. Its physical state has changed. Before hydration, the substance is usually solid. After hydration, the color and the volume may have changed, but the physical state has ...

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If you have two component mixture of A and B, most important reason for volume of mixing being zero is that when solution is ideal heterogeneous interactions (A - B) are the same as homogeneous (A - A and B - B). If interactions are the same than volume doesn't change when you mix components. Other reasons which contribute to non - ideality of mixing is size ...

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