Compounds are elements and its a pure substance with a gised composition.
Mixtures two or more subtances mixed to together.There are 2 type of mixtures.
Homegenous Mixtures (Solutions)-Two or more substances mixed but is uniform, you cant see the different mixtures.
Ex:Sugar mixed with water.The sugar dissolves and becomes one with the water.
Heterogeneous Mixtures-Two or more substances mixed but is not uniformed.You can see all the substances put into the mixture.
Ex:A salad, you can see whats all mixed in the sald and can pick it apart.
Helium is found in the 1st period of the periodic table. It also is part of the noble gases group in the last column (18th) of the table.
energy is required to move from one state or phase of matter to the next. Energy is used to make a liquid into a gas or a solid into a liquid.
Answer:
b
Explanation:
A pure substance has a constant composition and cannot be separated into simpler substances by physical means. There are two types of pure substances: elements and compounds.