Is baking bread a chemical or physical change? a chemical b physical c neither

What is the molar mass of a gas that has density of 2.054 g/l

What is the ph of a solution that has a hydrogen ion concentration of 1.0 * 10 -9 m?

What is a main difference between a mixture and a pure substance? a mixture is only a liquid, but a pure substance can be in any state. a mixture looks the same throughout, but a pure substance does not.1 a mixture can vary in composition, but a pure substance has a set composlo a mixture can be made up of a single compound, but a pure substance car