Choose all of the correct statements.
1-atmospheric oxygen gas is a pure substance
2-it is impossible to ever separate the components of a mixture
3-you dump a container of salt into a container of pepper to create a homogeneous mixture
4-you create a homogeneous mixture by completely dissolving your fruit punch powder in water
5-sodium and chlorine combine to form the pure substance of table salt
6-a pure substance is formed when you combine all of the ingredients for a salad for lunch