1. 10.0 g of CaCO 3 on heating gave 4.4 g of CO 2 and 5.6 g of CaO. The observation is in agreement with the law of conservation of mass.

2. hydrogen and oxygen are combined to form two compounds the hydrogen content in one of the compound is 5.93 % and another is 11.2 % is this obey the law of multiple proportion.

3. On analysis it was found that the black oxide of Copper and red oxide of copper contains 80 and 89% of copper respectively Is this obeys the law of multiple proportion.

4.when 8.4 G of NaHco3 is added to the solution of Acetic Acid weighing 20 gram if it is observed that 4.4 gram of Co2 is released into the atmosphere and Residue is left Behind what is the mass of left Residue.

According to the law Mass of reactants = mass of product, here `underset(10 g)(CaCO_(3))rarr underset(4.4 g)(CO_(2))+underset(x)(CaO)` Hence, x = 10 g - 4.4 g = 5.6 g Which is mass of CaO.d
In the first compound Hydrogen = 5.93 % Oxygen = `(100-5.93)% = 94.07 %` In the second compound Hydrogen = 11.2 % Oxygen `= (100-11.2)%=88.8%` In the first compound the number of parts by mass of oxygen that combine with one part by mass of hydrogen `=(94.07)/(5.93)=15.86` parts ...
(The ratio of Cu combining with fixed weight of oxygen in black and red oxide is 1 : 2 respectively. Step by step solution by experts to help you in doubt clearance & scoring excellent marks in exams.) {Check something more in the above attachment!}
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