how would you distinguish between baking soda and washing soda by heating
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Baking powder on heating decomposes to give sodium carbonate, water and carbon dioxide according to the following equation
NaHCO3 → Na2CO3 +H2O +CO2
Washing soda (Na2CO3.10H2O) on the other hand, on heating below 373 K loses 9 molecules of water of crystallization and forms Sodium carbonate monohydrate (Na2CO3.H2O). On heating above 373 K, this monohydrate changes to anhydrous white powder called soda ash – Na2CO3 but does not decompose further.
Na2CO3.10H2O → Na2CO3.H2O + 9 H2O (Below 373 K)
Na2CO3.H2O → Na2CO3 + H2O (above 373 K)
Soda ash
Therefore baking soda decomposes on heating with evolution of CO2, while washing soda loses its water of crystallization and forms soda ash but there is no evolution of CO2.
hope it's helpful
NaHCO3 → Na2CO3 +H2O +CO2
Washing soda (Na2CO3.10H2O) on the other hand, on heating below 373 K loses 9 molecules of water of crystallization and forms Sodium carbonate monohydrate (Na2CO3.H2O). On heating above 373 K, this monohydrate changes to anhydrous white powder called soda ash – Na2CO3 but does not decompose further.
Na2CO3.10H2O → Na2CO3.H2O + 9 H2O (Below 373 K)
Na2CO3.H2O → Na2CO3 + H2O (above 373 K)
Soda ash
Therefore baking soda decomposes on heating with evolution of CO2, while washing soda loses its water of crystallization and forms soda ash but there is no evolution of CO2.
hope it's helpful
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