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Zolol [24]
3 years ago
5

You are performing a gradient elution and are instructed to begin with a low polarity solvent (petroleum ether) and continue to

increase solvent polarity with MTBE. Why are the mobile phases added in order of increasing polarity rather than in the order of decreasing polarity?
Chemistry
1 answer:
Sophie [7]3 years ago
3 0

Answer:

The eluting strength of a solvent is primarily related to how strongly it adsorbs onto the  adsorbent and because typical adsorbents are highly polar; thus, eluting strength increases  with solvent polarity.

Explanation:

The polarity of a solvent makes it more suitable for elution in a polar adsorbent. Hence the choice of solvents should be in order of increasing rather than decreasing polarity. polarity must increase and not decrease

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How does Bohr’s model of the atom compare with Thomson’s model?
Ilya [14]
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Thomson's model, or the plum pudding model, it describes atoms as spheres of positively charged matter, in which electrons are embedded in.
The key difference is the locations of, and the motions of the electrons.
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What could reduce the heat island effect around cities?
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2 years ago
When phenolphthalein indicator is added to a colorless solution with a pH of 10, a student observes and concludes that the teste
madam [21]

Answer:

3.  turns pink and is basic

Explanation:

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4 0
3 years ago
How do you make fried chicken im white and don't know how to season
Tpy6a [65]

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Explanation:

4 0
2 years ago
Given the following reaction and data, A + B → Products
natima [27]

Answer:

a. Rate = k×[A]

b. k = 0.213s⁻¹

Explanation:

a. When you are studying the kinetics of a reaction such as:

A + B → Products.

General rate law must be like:

Rate = k×[A]ᵃ[B]ᵇ

You must make experiments change initial concentrations of A and B trying to find k, a and b parameters.

If you see experiments 1 and 3, concentration of A is doubled and the Rate of the reaction is doubled to. That means a = 1

Rate = k×[A]¹[B]ᵇ

In experiment 1 and to the concentration of B change from 1.50M to 2.50M but rate maintains the same. That is only possible if b = 0. (The kinetics of the reaction is indepent to [B]

Rate = k×[A][B]⁰

<h3>Rate = k×[A]</h3>

b. Replacing with values of experiment 1 (You can do the same with experiment 3 obtaining the same) k is:

Rate = k×[A]

0.320M/s = k×[1.50M]

<h3>k = 0.213s⁻¹</h3>

6 0
3 years ago
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