Solutions, Acids, and Bases Online Practice

Question

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14 of 1814 of 18 Items

Question
Use the periodic table to answer the 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 acid is strongest?

(1 point)
Responses

HCl
HCl

HBr
HBr

PH3
PH 3

H2S

Answer 1

To determine which acid is the strongest based on the periodic trends and the options provided, we need to consider the strength of the acids, particularly those containing hydrogen.

1. HCl (Hydrochloric acid): A strong acid because chlorine (Cl) is electronegative, and it can effectively stabilize the negative charge when it dissociates.

2. HBr (Hydrobromic acid): This is also a strong acid, and since bromine (Br) is further down in the group than chlorine, it has a larger atomic radius and a weaker bond with hydrogen, making it easier for HBr to dissociate in solution.

3. PH3 (Phosphine): While PH3 does contain hydrogen, it is not an acid; it is a neutral molecule. It does not produce H+ ions in solution.

4. H2S (Hydrosulfuric acid): This is a weak acid because sulfur (S) is less electronegative than chlorine and bromine, meaning it does not hold onto the hydrogen ions as well, but it's stronger than PH3.

Given these considerations, the strongest acid among the provided options is HBr (Hydrobromic acid).