During an investigation, similar effervescent tablets were dropped into a beaker containing cold water and a beaker containing tap water. the table below shows an incomplete record of the investigation. investigation results beaker time taken for the tablet to dissolve (seconds) cold water (50 ml) 68 tap water (50 ml) ?

The answer would be B. Less than 68 seconds as rate of reaction is higher for tap water because when you add a solute to cold water, it does not dissolve in the solvent as to putting the solute in room temperature or warm water.

your answer would be a. 12.5 kg

we can conclude that the melting point of table salt is above room temperature (it's actually 801 deg c). the melting point of mercury must be below room temperature (- 39 deg c).