2007-10-03 15:34:15 · 3 answers · asked by Anonymous in Science & Mathematics ➔ Chemistry
If your product is something that absorbs water form the air (many inorganic salts do this) you want to get the weight as soon as posible, or the measured weight will be larger than it should be.
2007-10-03 15:43:46 · answer #1 · answered by Flying Dragon 7 · 0⤊ 0⤋
Many substances that are soluble in water (and some that are insoluble) are hygroscopic, i.e. they absorb water from the atmosphere. If the substance left in the evaporating dish happens to be hygroscopic, then it will slowly absorb water from the atmosphere and, therefore, increase in weight with time.
2007-10-04 14:25:51 · answer #2 · answered by deedsallan 3 · 0⤊ 0⤋
If you leave the material in the evaporating basin exposed to the atmosphere for an excessive amount of time, it will probably absorb or react with the moisture in the atmosphere and that will affect your weighings.
2007-10-04 01:05:56 · answer #3 · answered by Anonymous · 1⤊ 0⤋