The compound YBa2Cu3O7, which shows superconductivity, has copper in oxidation state ______ assume that the rare earth element yttrium is in its usual +3 oxidation state.
Answer
$$ + {7 \over 3}$$
2
IIT-JEE 1991
Fill in the Blanks
The weight of $$1 \times 10^{22}$$ molecules of CuSO4.5H2O is ____.
Answer
4.14 g
3
IIT-JEE 1983
Fill in the Blanks
3 g of a salt of molecular weight 30 is dissolved in 250 g of water. The molality if the solution is _____.
Answer
0.4m
4
IIT-JEE 1980
Fill in the Blanks
The total no of electron present in 18 ml of water is ______.
Answer
$$6.02 \times 10^{24}$$
Questions Asked from Some Basic Concepts of Chemistry
On those following papers in Fill in the Blanks
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