What is the main difference between a pure substance and a mixture?

Pure substances are Broken down into other elements or compounds, while Mixtures are combined elements that can be broken down again into their original components.

Explanation:

Mixtures can vary with what they are made from, while pure substances are set as a certain composition already.

lithosphere and asthenosphere

b. acid is the correct answer @jayxboof all social media

acid : acids are those which accepts an electron-pairs.

base : bases are those which donates ab electron-pairs.

alkali : it is a base that dissolves in water. it is basically a base and the ph greater than 7.

hydroxide ion : it is a poly-atomic ion which is negatively charged.