3 years ago

An atomic model shows 19 protons, 20 neutrons, and 19 electrons. What is the mass number of the atom?

Chemistry

1 answer:

agasfer [191]3 years ago

7 0

The mass number of the atom is 39

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Answer:

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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

So, for $CH_3COOH$ , $K_a=1.8\times 10^{-5}$

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

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

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