Are lithium bicarbonate and​ magnesium bicarbonate both soluble in water?

Source: JEE Mains 2017 (National Level Examination of India)

Please do cite a reputed source along with your answer. Currently I have found a line from JD Lee (Concise Inorganic Chemistry 5th ed):

A Scan from JD Lee


According to this Wikipedia solubility table, lithium bicarbonate is soluble in water to $\pu{5.7 g/100mL}$ at $\pu{20^oC}$, while this Wikipedia page gives the solubility of magnesium bicarbonate as $\pu{0.077 g/100mL}$.

However, another source (found by Oscar Lanzi in his good answer), "The Solubility of Magnesium Carbonate in Aqueous Solutions of Certain electrolytes, The Journal of Physical Chemistry, Volume 7, pub. 1903, reports making two measurements of the solubility of magnesium bicarbonate and finding $\pu{3.1 g/100mL}$ and $\pu{2.0 g/100 mL}$. Note that this source is from 1903, but also that the the Wikipedia link above does not give a source for their value at all. At least one reason for the dearth of information regarding magnesium bicarbonate is that it easily decomposes and it cannot readily be isolated outside of aqueous solutions. My feeling is that the Wikipedia value seems low, and that the values reported in the Journal of Physical Chemistry seem more reasonable.

  • $\begingroup$ Lithium bicarbonate is also not available was a solid. See the OP' s own citation. $\endgroup$ – Oscar Lanzi Apr 14 '17 at 23:54

I beg to differ on magnesium bicarbonate. In https://books.google.com/books?id=bCfzAAAAMAAJ&pg=PA583&lpg=PA583&dq=magnesium+bicarbonate+solubility&source=bl&ots=3c8f8q4ocI&sig=XAY4Z50JRHq3FBRe8VPZjDf10sA&hl=en&sa=X&ved=0ahUKEwj91byQ3qPTAhVCOSYKHdNuDAw4ChDoAQgcMAE#v=onepage&q=magnesium%20bicarbonate%20solubility&f=false the solubility of magnesium bicarbonate is $3.06$ g/($100$mL).

  • 2
    $\begingroup$ +1 for the good find. I think the values reported in this paper make more sense than the values given by Wikipedia. Note that I modified my answer to include this source, and gave credit to you and your answer for finding it, for whatever that's worth. Again, good find. $\endgroup$ – airhuff Apr 14 '17 at 20:51

From NCERT (India) 11 page 296 under "The s-block elements":

The carbonates of lithium and magnesium decompose easily on heating to form the oxides and $\ce{CO2}$. Solid hydrogen carbonates are not formed by lithium and magnesium.


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