Answer asap! 1) what is a compound? 2) what are 3 properties of compounds? 3) what is a pure substance? 4) if a substance is not a pure substance, what is it?

1.) A compound is a thing that is composed of two or more (separate) elements.

2.) A compound cannot be separated easily, while its properties differ from where it originates from. It also is formed from chemical reactions.

3.) A pure substance, also known as chemical substance, is a material with constant composition and consistant properties.

4.) If a substance is not a pure substance, then it is an impure substance.

Hope this helped. :)

The  grandmother cell  is a hypothetical  neuronthat represents a complex but specific concept or object.[1]  it activates when a person "sees, hears, or otherwise sensibly discriminates"[2]  a specific entity, such as his or her grandmother. the term was in use at least as early as 1966 amongst staff and students in the department of experimental psychology, university of cambridge, england. a similar concept, that of the  gnostic neuron, was proposed two years later