Which of the following is the best example of law of conservation of mass [NCERT 1975]

Question: Which of the following is the best example of law of conservation of mass [NCERT 1975]

(a) 12 g of carbon combines with 32 g of oxygen to form 44 g of CO₂

(b) When 12 g of carbon is heated in a vacuum there is no change in mass

(c) A sample of air increases in volume when heated at constant pressure but its mass remains unaltered

(d) The weight of a piece of platinum is the same before and after heating in air


Correct Answer: (a) 12 g of carbon combines with 32 g of oxygen to form 44 g of CO₂


Question: Which of the following is the best example of law of conservation of mass [NCERT 1975] (a) 12 g of carbon combines with 32 g of oxygen to form 44 g of CO₂ (b) When 12 g of carbon is heated in a vacuum there is no change in mass (c) A sample of air increases in volume when heated at constant pressure but its mass remains unaltered (d) The weight of a piece of platinum is the same before and after heating in air




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