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    Making notes. Both my AQA textbook and Chemrevise says that Mg(OH)2 are insoluble in water so will suspend.

    However, the specification saysthat Mg(OH)2 is sparingly soluble.

    What would I write in the exam to get the mark?
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    Wikipedia says: 0.00064 g/100 mL (25 °C)

    i.e. 156250 cm3 of water is need to dissolve 1 g

    Sigma Aldrich say this:

    Hmm, that didn't copy and paste well, here's a link: http://www.sigmaaldrich.com/united-k...olubility.html

    i.e. Mg(OH)2 is practically insoluble.

    If you have a saturated solution, it would have a pH of around 10.34.

    Pro tip: always go with the specification.
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    In AQA textbook, it says that Mg(OH)2 is sparingly soluble. But I did get confused by Chemrevise, it says it's insoluble.
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    If last years mark scheme is anything to go by, you should avoid saying insoluble and should put sparingly soluble.
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    Sparingly soluble. Look here

    https://www.chemguide.co.uk/inorgani...olubility.html
 
 
 
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