Advertisements
Advertisements
प्रश्न
Copper sulphate reacts with sodium hydroxide to form a blue precipitate of copper hydroxide and sodium
sulphate. In an experiment, 15.95 g of copper sulphate reacted with 8.0 g of sodium hydroxide to form
9.75 g of copper hydroxide and 14.2 g of sodium sulphate. Which law of chemical combination is illustrated by this data ? Give reason for your choice.
उत्तर
Chemical reaction:
CuSO4 + NaOH → Cu(OH)2 + NaSO4
15.94g 8.0g 9.75g 14.2g
Total mass of reactants = Total mass of products
23.95g 23.95 g
The above reaction and data illustrate the law of conservation of mass which was proposed by Antoine Lavoisier.
The law states that the mass of elements remains constant over time i.e. mass can neither be created nor destroyed. In the above reaction, the mass of reactants (23.95 g) is exactly equal to the mass of their product (23.95 g). There is no change in the mass of the product after the reaction.
APPEARS IN
संबंधित प्रश्न
In a reaction, 5.3 g of sodium carbonate reacted with 6 g of acetic acid. The products were 2.2 g of carbon dioxide, 0.9 g water and 8.2 g of sodium acetate. Show that these observations are in agreement with the law of conservation of mass.
Sodium carbonate + acetic acid → sodium acetate + carbon dioxide + water
State the law of conservation of mass.
Name the law of chemical combination which was given by Lavoisier.
State the law of conservation of mass. Give one example to illustrate this law.
The law of conservation of mass was given by :
Potassium chlorate decomposes, on heating, to form potassium chloride and oxygen. When 24.5 g of potassium chlorate is decomposed completely, then 14.9 g of potassium chloride is formed. Calculate the mass of oxygen formed. Which law of chemical combination have you used in solving this problem ?
State the ‘law of conservation of mass’.
Complete the statement given below by filling in the blanks with the correct words.
Atoms contain ________ with positively charged ________.
Select the correct answer from A, B, C, D & E for the statement given below:
In Landolt’s experiment – the form in which the chemical energy stored up in the reactants __________ is released.
Why does a light paddle wheel placed in the path of cathode rays begin to rotate, when cathode rays fall on it?
