Why does one add excess hot solvent to a solution before hot gravity filtration through fluted filter paper

What shape would a molecule with two bound groups and two lone pairs have?

Adepositional also feature that forms where a stream enters a lake or an ocean is a

When the chemicals iron sulfide (fes) and hydrochloric acid (hcl) are combined, bubbles appear from the mixture. 1. does the appearance of bubbles indicate a physical or chemical change? 2. why do the bubbles indicate this change? 3. what property is this?