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pH question help plz (1 Viewer)

xxshazz

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What is the pH of a 0.2mol/L solution of sulfuric acid?(assume that the acid is fully dissociated.)

how would u work this out? ty :)
 

Julz666

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As sulfuric acid is diprotic (H2SO4), there will be a concentration of 0.4 moles of H+ ions in a 0.2 molar solution
thus we use the formula
pH=-logH+
pH=-log(0.4)
pH=0.699
 

paul5666

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concentration of H+ is 0.4
but the pH is a logarithmic scale
i.e. pH=-log[H+]
=-log(0.4)
=0.699

use your calculator.
 

alexx-12

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Ph means potential hydrogen
since sulfuric acid (H2SO4) has two hydrogen atoms we multiply the number of moles by two
 

adomad

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hence if you have 0.2 moles of H2SO4 you must double it to get the moles of hydrogen ions ( from the balanced equation)
 

unano

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-log[0.4] = 0.40 (2sf) not 0.699
use ur calculator lol.
 

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