What is the conservation of mass pertains the chemical change and physical change?

Asingle atom of an element has 21 neutrons, 20 electrons, and 20 protons. which element is it? ok o z

6. what does the symbol ah stand for? o one calorie given off by a reaction the specific heat of a substance the heat capacity of a substance the heat of reaction for a chemical reaction

Write the balanced equation for a reaction between aqueous nitric acid (hno3) and solid lithium metal (this is a single replacement reaction)