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](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgCjr3fcKzWue1_TPEMpNQHdWyqnMsW2VqOtR4Zy1dCD9yMhJvOxJYYfMZH4TpzLuY0iwxNjeaOdOIFXSLOk_zV6lv62FjQ1Nm3Dzn2pR6chAWcp_ul7fUSYSQeGz_VnREsbexl6Gt3MR5rlzFReCw1Q7QIo-OSjEmjj-Am6vEv0Th1Gbmw3sCtpui7/s1920/Which%20of%20the%20following%20is%20the%20best%20example%20of%20law%20of%20conservation%20of%20mass%20%5BNCERT%201975%5D.jpg "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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