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What is percent by mass of water in the hydrate sodium bicarbonate octahydrate?

User OsQu
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1 Answer

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Answer:

50%

Step-by-step explanation:

Formula of this hydrate is given as:

Sodium bicarbonate octahydrate = NaHCO₃ . 8H₂O;

To find the percent by mass of water;

  • Sometimes it is good to know the percent by mass of elements or groups present in a compound.
  • Find the formula mass by summing the atomic masses.
  • Determine the percentage composition of an atom or group by expressing as a percentage of the formula mass.

Formula mass of NaHCO₃ . 8H₂O;

= 23 + 1 + 12 + 3(16 ) + 8[2(1) + 16]

= 228g/mol

for the 8H₂0 = 8(18) = 144

%H₂O =
(144)/(288) x 100 = 50%

User Shafiq
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