Answer:
49.4 g Solution
Explanation:
There is some info missing. I think this is the original question.
<em>A chemistry student needs 20.0g of acetic acid for an experiment. He has 400.g available of a 40.5 % w/w solution of acetic acid in acetone. </em>
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Calculate the mass of solution the student should use. If there's not enough solution, press the "No solution" button. Round your answer to 3 significant digits.</em>
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We have 400 g of solution and there are 40.5 g of solute (acetic acid) per 100 grams of solution. We can use this info to find the mass of acetic acid in the solution.
Since we only need 20.0 g of acetic acid, there is enough of it in the solution. The mass of solution that contains 20.0 g of solute is:
We are asked for the energy emitted by a photon using the wavelength given. In this case, we use the planck relation that correlates energy and wavelength using Planck's constant and speed of light as constant of proportionality. The formula is E = hc / w where h is equal to 6.626 x10-34 Js and c is equal to 3 x10 8 m/s. E then is equal to 1.55 x10-24 J
Answer: All the points apply for colloids.
Explanation: This question can be answered only by looking at the properties of colloids:
- The particle size of these systems range from 1nm to 1mm.
- These are generally considered as heterogeneous mixtures but have some properties of homogeneous mixtures. There is some physical boundary present between solute and solvent.
- These solutions cannot be separated by ordinary filtration.
- Tyndall effect: This effect is generally seen in colloidal solutions or solutions having very fine suspension. This effect is basically the scattering of light by the particles. This effect can be seen in the sky when sunlight is scattered by clouds.
- These solutions have small particle size thus it cannot be seen from bare eyes, thus we need optical microscope.
- Cloud, Milk, Fog and Smoke are some of the examples of Colloidal solutions.
These properties enlisted above show that all the points given in the question are correct for colloidal solutions.
<span>Both provide approaches to confirming the result of experimentation. Repetition can be developed by one scientist or team continually achieving the expected result but replication requires an independent person or team shows thay can arrive at the same answer independently</span>
