Risteen is quoted by Mellor as saying that, "I cannot see what warrant there is for assuming that when a weight A of one substance combines with another whose weight is B, the weight of the resulting compound is universally and necessarily A + B." A.D. Risteen is obviously false and this statement is completely invalid. The mass of an object, as proved by multiple scientists, is always conserved unlike the volume, density or any other atomic property.
John Dalton stated that all atoms must have its own properties, especially its own characteristic mass. Dalton's second postulate of the atomic theory states that all atoms of a given element are identical, both in mass and properties. These idea's helped early scientists formulate the two important laws on the conservation of matter. Antoine Lavoisier formed the law of conservation of matter and found out that the sum of the masses of reactants always equaled the sum of the masses of the products. If each atom has a different characteristic mass, and the same number of atoms exists before and after the reaction, the total masses before and after must be the same. French chemist Joseph Louis Proust formed the law of constant composition, which stated that the masses of elements did not vary, regardless of the samples origin. Risteen is obviously proven wrong because mass must be conserved as proven by Lavoisier and Proust.
The mass of an object is always conserved unlike other properties such as volume, density and temperature. The volume of an object can change by taking a different shape, the temperature is never constant because it changes regularly with the weather or within a reaction and the density can change by adding or subtracting the amount of a substance in a solution. The reason why mass should be conserved is because in order for a scientific discovery or experiment to take place there has to be a form of consistency.
