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In what order do these acids rank HBr, HCl, HI, H2Se, H2S, CH4, and H2O?
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May Chen
In what order do these acids rank HBr, HCl, HI, H2Se, H2S, CH4, and H2O?
Ranking these acids in order of their acid strength, the strongest acid is HI with a pKa of -10, then HBr with a pKa of -9, the HCl with a pKa of -8, next is H2Se with a first pKA of 3.89, then H2S with a first pKa of 7, then water with a pKa of 15.7 and finally methane with a pKa of 48. For your reference, the pKa scale is a log scale where the stronger the acid is the lower the pKa. Each unit increase in the pKa corresponds to a tenfold decrease in the acidity of the compound. This means that HI is 10 to the 58 power times more acidic than methane. That’s a mind boggling range of acidity!
Ranking these acids in order of their acid strength, the strongest acid is HI with a pKa of -10, then HBr with a pKa of -9, the HCl with a pKa of -8, next is H2Se with a first pKA of 3.89, then H2S with a first pKa of 7, then water with a pKa of 15.7 and finally methane with a pKa of 48. For your reference, the pKa scale is a log scale where the stronger the acid is the lower the pKa. Each unit increase in the pKa corresponds to a tenfold decrease in the acidity of the compound. This means that HI is 10 to the 58 power times more acidic than methane. That’s a mind boggling range of acidity!
Ranking these acids in order of their acid strength, the strongest acid is HI with a pKa of -10, then HBr with a pKa of -9, the HCl with a pKa of -8, next is H2Se with a first pKA of 3.89, then H2S with a first pKa of 7, then water with a pKa of 15.7 and finally methane with a pKa of 48. For your reference, the pKa scale is a log scale where the stronger the acid is the lower the pKa. Each unit increase in the pKa corresponds to a tenfold decrease in the acidity of the compound. This means that HI is 10 to the 58 power times more acidic than methane. That’s a mind boggling range of acidity!
Ranking these acids in order of their acid strength, the strongest acid is HI with a pKa of -10, then HBr with a pKa of -9, the HCl with a pKa of -8, next is H2Se with a first pKA of 3.89, then H2S with a first pKa of 7, then water with a pKa of 15.7 and finally methane with a pKa of 48. For your reference, the pKa scale is a log scale where the stronger the acid is the lower the pKa. Each unit increase in the pKa corresponds to a tenfold decrease in the acidity of the compound. This means that HI is 10 to the 58 power times more acidic than methane. That’s a mind boggling range of acidity!
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Order? CH4, H20, H2S, H2Se, HBr, HCl, HI.
That’s alphabetical order, of course, using the ASCII/Unicode convention that numerals come before letters.
If you meant some other order, like increasing molecular weight or decreasing boiling point, you need to write a clearer question.
Order? CH4, H20, H2S, H2Se, HBr, HCl, HI.
That’s alphabetical order, of course, using the ASCII/Unicode convention that numerals come before letters.
If you meant some other order, like increasing molecular weight or decreasing boiling point, you need to write a clearer question.
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