YASH CLASSES
Some basic concepts of chemistry [Law of constant composition ]
Q1. 8.2g of copper metal is first converted to copper nitrate
(by reaction with HNO3 )and subsequently to 9.2 g CuO.
In another experiment 2.20 g copper gave 2.87 g CuO on combustion.
Show that the
above data verify the law of constant composition.
Q2. 7.5g of copper metal is first converted to copper nitrate
(by reaction with HNO3 )and subsequently to 8.7 g CuO.
In another experiment 5.20 g copper gave 7.1 g CuO on combustion.
Show that the
above data verify the law of constant composition.
Q3. 3.2g of copper metal is first converted to copper nitrate
(by reaction with HNO3 )and subsequently to 5.2 g CuO.
In another experiment 3.20 g copper gave 3.87 g CuO on combustion.
Show that the
above data verify the law of constant composition.
Q4. Copper sulphate crystal contains 35.45% Cu and 45% H2O.
If the law of constant composition is true. Calculate the weight
of copper
required to obtained 50 g of crystal- line copper sulphate.
[use – CuSO4.5H2O ]
Q5. Copper sulphate crystal contains 27% Cu and 55% H2O.
If the law of constant composition is true. Calculate the weight
of copper
required to obtained 70 g of crystal- line copper sulphate.
[use – CuSO4.5H2O ]
Q6. Copper sulphate crystal contains 21% Cu and 50% H2O.
If the law of constant composition is true. Calculate the weight
of copper
required to obtained 85 g of crystal- line copper sulphate.
[use – CuSO4.5H2O ]
Q7. 5.2g of copper metal is first converted to copper nitrate
(by reaction with HNO3 )and subsequently to 7.2 g CuO.
In another experiment 3.20 g copper gave 3.77 g CuO on combustion.
Show that the above data verify the law of constant composition.
Q8. Copper sulphate crystal contains 15.45% Cu and 45% H2O.
If the law of constant composition is true. Calculate the weight
of copper required to obtained 50 g of crystal- line copper sulphate.
[use – CuSO4.5H2O ]