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Volume of `0.1M HCl` required to react completely with 1g equimolar mixture of `Na_(2)CO_(3)` and `NaHCO_(3)` is |
Answer» Calculate of no. of moles of components in the mixture Let x g of `Na_(2)CO_(3)` is present in the mixture. `therefore(1-x)g` of `NaHCO_(3)` is present in the mixture. Molar mass of `Na_(2)CO_(3)` ,brgt `=2xx23+12+3xx16=106" g "mol^(-1)` and molar mass of `NaHCO_(3)` `=23xx1+1+12+3xx16=84" g "mol^(-1)` No. of moles of `Na_(2)CO_(3)` in x g`=(x)/(106)` No. of moles of `NaHCO_(3)` in (1-x)`g=(1-x)//84` As given that the mixture contains equimolar amounts of `Na_(2)CO_(3)` and `NaHCO_(3)` therefore. `(x)/(106)=(1-x)/(84)` `=106-106x=84x` `106=190x` `thereforex(106)/(190)=0*558g` `therefore` No. of moles of `Na_(2)CO_(3)` present `=(0*558)/(106)=0*00526` and no. of moles of `NaHCO_(3)` present `=(1-0*558)/(84)=0*00526` Calculation of no. of moles of of HCl required `Na_(2)CO_(3)+2HClto2NaCl+H_(2)O+CO_(2)` `NaHCO_(3)+HClto NaCl+H_(2)O+CO_(2)` As can be seen, each mole of `Na_(2)CO_(3)` needs ltBrgt 2 moles of HCl, `therefore0*00526` mole of `Na_(2)CO_(3)` needs `=0*00526xx2=0*01052` moles Each mole of `NaHCO_(3)` needs 1 mole of HCl. `0*00526=0*00526` mole Total amount of HCl needed will be `=0*01052+0*00526=0*01578` mole `0*1` mole of 0.1 M HCl are present in 1000 mL of HCl `therefore0*01578` mole of `0*1` M HCl will be present n `=(1000)/(0*1)xx0*01578=157*8mL` |
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