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3 years ago

14

Which choice is an element? Question 2 options: air (N2 mixed with O2 , and CO2 ) sodium chloride (NaCl) oxygen (O2 ) water (H2O

)

1 answer:

Ber [7]3 years ago

7 0

Answer:

oxygen (O2 )

Explanation:

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A solution of acetic acid has a pH of 3.45. What is the concentration of acetic acid in this solution? Ka for CH3COOH is 1.8×10-

Serjik [45]

Answer:

0.007 M

Explanation:

pH is defined as the negative logarithm of the concentration of hydrogen ions.

Thus,

pH = - log [H⁺]

The expression of the pH of the calculation of weak acid is:-

$pH=-log(\sqrt{k_a\times C})$

Where, C is the concentration = ?

Given, pH = 3.45

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$3.45=-log(\sqrt{1.8\times 10^{-5}\times C})$

$\log _{10}\left(\sqrt{1.8\cdot \:10^{-5}C}\right)=-3.45$

C = 0.007 M

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3 years ago