Use the periodic table to answer the question.

Question

An illustration shows the periodic table of elements with elements arranged in increasing order of atomic number in 18 columns (groups) and 7 rows (periods). The electronegativity of elements increases from left to right, across a period. The hydrogen on the left is included in group with medium electronegativity. Also, fluorine is shown as element with highest electronegativity.

Based on patterns in the periodic table, which list shows the acids in order from strongest to weakest?

(1 point)
Responses

HCl, PH3, H2S
HCl, PH 3 , H 2 S

HCl, H2S, PH3
HCl, H 2 S, PH 3

PH3, H2S, HCl
PH 3 , H 2 S, HCl

H2S, PH3, HCl

Answer 1

To determine the order of acids from strongest to weakest among the given choices (HCl, H2S, and PH3), we need to consider the strength of the acids based on their electronegativities and the stability of their conjugate bases.

1. HCl (hydrochloric acid): This is a strong acid and dissociates completely in water, making it the strongest acid among the three. Chlorine is highly electronegative, which makes HCl a strong acid.

2. H2S (hydrosulfuric acid): This is a weak acid compared to HCl, as sulfur is less electronegative than chlorine. H2S does not dissociate completely in solution.

3. PH3 (phosphine): This is generally not considered an acid in the same way that HCl and H2S are, and it is significantly weaker in acidic character than both HCl and H2S.

Based on these considerations, the correct order from strongest to weakest acid is:

HCl > H2S > PH3

Therefore, the correct response is:

HCl, H2S, PH3