Chapter 2: Matter and Change Elements and compounds

Learning Target You will: Classify whether matter is a pure substance, element, compound, mixture, solution, heterogeneous or homogeneous.

Matter Concept Map Matter Pure Substance Mixture You will classify whether matter is a pure substance, element, compound, mixture, solution, heterogeneous or homogeneous.

Pure Substance Element Compound Continued … You will classify whether matter is a pure substance, element, compound, mixture, solution, heterogeneous or homogeneous.

Mixture Homogeneous Heterogeneous Continued … You will classify whether matter is a pure substance, element, compound, mixture, solution, heterogeneous or homogeneous.

Pure Substance vs. Mixture Pure substance: cannot be separated further by physical means Mixture: can be separated by physical means You will classify whether matter is a pure substance, element, compound, mixture, solution, heterogeneous or homogeneous.

Element vs. Compound Element: cannot be separated into simpler substances Example: mercury Can see on the periodic table Compound: atoms of different elements chemically combined Example: mercury sulfide Must be chemically taken apart You will classify whether matter is a pure substance, element, compound, mixture, solution, heterogeneous or homogeneous.

Continued … Mixture Homogeneous Heterogeneous You will classify whether matter is a pure substance, element, compound, mixture, solution, heterogeneous or homogeneous.

Homogeneous vs. Heterogeneous Homogeneous: the same throughout Example: stainless steel Heterogeneous: not the same throughout Example: granite You will classify whether matter is a pure substance, element, compound, mixture, solution, heterogeneous or homogeneous.

Practice Classify each of the following types of matter as an element, a compound, or a mixture and provide reasons for their answers. Epsom salt (magnesium sulfate) Hydrogen peroxide (H2O2) Mercury (Hg) Sweetened iced tea Compound; it is composed of at least two elements. Compound; it is composed of two elements. Element; its symbol shows that it is composed of only one kind of matter. Mixture; it has a composition that can vary. You will classify whether matter is a pure substance, element, compound, mixture, solution, heterogeneous or homogeneous.

Separation techniques Distillation Electrolysis Filtration separation process water is boiled off, changed to steam, and leaves a precipitate. steam is collected & cooled, condensing to pure water. using an electric current to drive a non- spontaneous chemical reaction can be used to separate compounds. Separates a liquid from a solid Liquid passes through filter paper and solid remains You will classify whether matter is a pure substance, element, compound, mixture, solution, heterogeneous or homogeneous.

Examples Liquid A and Liquid B are clear liquids. They are placed in open containers and allowed to evaporate. When evaporation is complete, there is a white solid in container B but no solid in container A. From these results, what can you infer about the two liquids? Liquid A is probably a substance. Liquid B is a mixture. A clear liquid in an open container is allowed to evaporate. After three days, a solid is left in the container. Was the clear liquid an element, a compound, or a mixture? How do you know? The liquid was not an element because a solid was left when the liquid evaporated. A physical process, such as evaporation, cannot be used to break down a compound. Therefore, the liquid was a mixture. You will classify whether matter is a pure substance, element, compound, mixture, solution, heterogeneous or homogeneous.

You try … In your notebook, design an experiment that employs all the separation techniques mentioned. You will classify whether matter is a pure substance, element, compound, mixture, solution, heterogeneous or homogeneous.

Summarize how you feel … You will: Classify whether matter is a pure substance, element, compound, mixture, solution, heterogeneous or homogeneous.