Answer: 
Explanation: Because barium is in Group 2, it forms ions with a charge of +2. Fluorine, in Group 17, form ions with a charge of -1. Cross the charges to get the subscripts (Since Ba has a charge of +2, F has a subscript of 2. Because F has a charge of -1, Ba needs a subscript of 1). Therefore, a formula unit of the compound is
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Explanation:
The sulfonation of the naphthalene yield 2 products under different conditions:
<u>When the reaction is carried at 80 °C, 1-naphthalenesulfonic acid is the major product because it is kinetically favoured product as arenium ion formed in the transition state corresponding to 1-naphthalenesulfonic acid is more stable due to better resonance stabilization.
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<u>When the reaction is carried at 160 °C, 2-naphthalenesulfonic acid is the major product as it is more stable than 1-naphthalenesulfonic acid because of steric interaction of the sulfonic acid group in 1-position and the hydrogen in 8-position.</u>
The products are shown in image below.
It would be an opinion because she doesn't exactly know what happened.
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