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2 years ago

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A chemist wants to use an element with a large electronegativity for an experiment. Based on trends in the periodic table, which

of the following groups has the largest electronegativity. Alkali Metals Halogens Noble Gases Alkaline Earth Metals

1 answer:

Sidana [21]2 years ago

6 0

Answer:

Halogens

Explanation:

Electronegativity increases from <em>left to right</em> in the Periodic Table (see image).

We ignore the elements of Group 18 (the noble gases) because they are quite unreactive.

So, the most electronegative elements are those in Group 17 (the <em>halogens</em>).

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Answer:

1. $3.57\times 10^{-4}$ was the $K_a$ value calculated by the student.

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Explanation:

1.

The $pH$ value of Aspirin solution = 2.62

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2.

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$C_2H_5NH_2+H_2O\rightleftharpoons C_2H_5NH_3^{+}+OH^-$

initially

c 0 0

At equilibrium

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The expression of dissociation constant :

$K_b=\frac{[C_2H_5NH_3^{+}][OH^-]}{[C_2H_5NH_2]}$ :

$K_b=\frac{x\times x}{(c-x)}$

$=\frac{0.00741\times 0.00741}{(0.100-0.00741)}$

$K_b=5.93\times 10^{-4}$

$5.93\times 10^{-4}$ was the $K_b$ of ethylamine value calculated by the student.

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