What is the law of conservation of mass? how is it related to balancing chemical equations

An uncovered pot of water lies out in the sun. which statements correctly describe what happens at the surface of the liquid water? 1. the vapor pressure remains constant regardless of the water temperature. 2. the vapor pressure is produced by water molecules that have evaporated. 3. the vapor pressure increases as the sun heats the water in the pot. 4. evaporation stops once the vapor pressure reaches a certain point. 5. evaporation and condensation both occur on the liquid’s surface.

Why hydrochloric acid neutralized first when you titrate a mixture of hcl& ch3cooh against standard sodium hydroxide

An atom of element x has one more shell of electrons than an atom of beryllium, but it has one less valance electron than beryllium. which element is x