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Rainbow [258]
2 years ago
8

Potassium is an alkali metal that is one of the electrolytes needed by the human body to conduct nerve impulses. The majority of

potassium
(93.26%) occurs as potassium-39. The rest is either potassium-40 (0.01%)
or potassium-41 (6.73%). *
pls show work for how you got answer!!
Chemistry
1 answer:
Stells [14]2 years ago
4 0

Answer:

39.13

Explanation:

To find that atomic mass of this potassium, we follow the steps below:

 Given parameters:

Abundance of K - 39  = 93.26%

Mass of K - 39  = 39

Abundance of K - 41  = 6.73%

Mass of K - 41 = 41

To find the average atomic mass;

Average atomic mass  =( mass x abundance of k -39 ) +( mass abundance of k- 41)

Average atomic mass =  (39 x  93.26%) + (41 x6.73%  )  = 39.13

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<u>Answer:</u> The correct answer is Option d.

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We are given:

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To calculate the average molecular mass of the mixture, we use the equation:

\text{Average molecular weight of mixture}=\frac{_{i=1}^n\sum{\chi_im_i}}{n_i}

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m_i = molar masses of i-th species

n_i = number of observations

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\text{Average molecular weight}=\frac{(\chi_{CH_4}\times M_{CH_4})+(\chi_{C_2H_4}\times M_{C_2H_4})+(\chi_{C_2H_2}\times M_{C_2H_2})+(\chi_{C_2H_2O}\times M_{C_2H_2O})}{4}

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