| 1. |
2.0 g of a mixture of Na2 CO3 and NaHCO3 was heated when its weight reduced to 1.876 g. Determine the percentage composition of the mixture. |
|
Answer» The mixture is 53.2 % Na2CO3 and 46.8 % NaHCO3Explanation:When you HEAT a mixture of Na2CO3 and NaHCO3 only the NaHCO3 decomposes.The equation for the decomposition is2NaHCO3(s)→Na2CO3(s)+CO2(g)+H2O(g)The loss in mass is caused by the loss of H2O and CO2 (equivalent to the loss of H2CO3).The loss in mass is (220–182)g=38gThis corresponds to 38gH2CO3×1 mol H2CO3 62.02g H2CO3=0.613 mol H2CO3∴ Moles of NaHCO3=0.613mol H2CO3×2 mol NaHCO31mol H2CO=1.225 mol NaHCO3 and Mass of NaHCO3=1.2225mol NaHC3×84.01 NaHCO31mol NaHCO3=102.9 g NaHCO3The loss of mass after heating corresponds to 102.9 g of original NaHCO3The rest of the original mixture must have been Na2CO3 .Mass of original Na2CO3=220g–102.9g=117.1 g% Na2CO3=117.1g220g×100%=53.2%NaHCO3=102.9g220g×100%=46.8%Explanation:Please MARK as BRAINLIEST answer and follow me please and thank me please Because I am a very good boy |
|