For the following:
i) HClO4 > HBrO4 > HIO4
ii) NH3 > PH3 > AsH3 > SbH3
iii) HOClO3 > HOClO2 > HOClO > HOCl
iv) HBr>HCl>HF
The order of acidity is correct for which series?
1. ) all are correct
2. ) ii and iii
3. ) ii and iv
4. ) ii
5. ) i, iii, iv
I don't see the correct answer listed. Tell us what you think (and why) and someone will be glad to comment.
I've been able to rule out a few of them, but I'm not sure if it is right, and how to reason one of them.
I don't know how to go about reasoning for i).
For ii), bond lengths down a group increase, meaning that the compound is more acidic, making this one false.
For iii), the more central O atoms there are, the more acidic, making this one true.
For iv), the same applies as for ii), making this one true.
I'm guessing that i) is true since the only option that satisfies the statements that we know is 5).
answer 1 3 4
To determine the correct order of acidity for the given series, let's analyze each series individually.
i) HClO4 > HBrO4 > HIO4
This series is arranged in decreasing order of the strength of the oxyacids. The strength of an oxyacid depends on the electronegativity of the central atom and the number of oxygen atoms attached to it. In this case, chlorine (Cl) is more electronegative than bromine (Br), which is more electronegative than iodine (I). Therefore, the order of acidity is correct for this series.
ii) NH3 > PH3 > AsH3 > SbH3
This series is arranged in decreasing order of the strength of the bases. The strength of a base depends on the electronegativity and atomic size of the central atom. In this case, nitrogen (N) is more electronegative than phosphorus (P), which is more electronegative than arsenic (As), and antimony (Sb) is the least electronegative. Additionally, as we move down the group, the atomic size increases, making the central atom less effective at accepting a proton. Therefore, the order of basicity is correct for this series.
iii) HOClO3 > HOClO2 > HOClO > HOCl
This series is arranged in decreasing order of the strength of the oxyacids. Similarly to series i), the strength of an oxyacid depends on the electronegativity of the central atom and the number of oxygen atoms attached to it. In this case, the order of oxygen atoms decreases, resulting in a decrease in acid strength. Therefore, the order of acidity is correct for this series.
iv) HBr > HCl > HF
This series is arranged in decreasing order of the strength of the binary acids. The strength of a binary acid depends on the polarity and bond strength. In this case, bromine (Br) is less electronegative than chlorine (Cl), resulting in a weaker bond to hydrogen (H). Fluorine (F) is the most electronegative, making the bond to hydrogen even weaker. Therefore, the order of acidity is correct for this series.
Based on the explanations above, the correct answer is 1.) all are correct.