Pure Substances and Mixtures Mid Unit Science Test
Mechanical Mixture
(aka Heterogeneous Mixture) a substance in which the particles are not uniformly scattered.
Describe The 5 Main Points of Particle Theory
1. All matter is made up of particles (elements and compounds) 2. There are empty spaces between the particles. 3. Particles are always moving. 4. Particles have attractive forces between them. 5. The spaces between particles expand when heated and the particles move faster.
solution
A homogeneous mixture of two or more substances
element
A pure substance that cannot be broken down into any other substances by chemical or physical means
law
A rule that explains aspects of the natural universe but can not explain why
Solid
A state of matter that has a definite shape and volume
Liquid
A state of matter that has no definite shape but has a definite volume.
Gas
A state of matter with no definite shape or volume
compound
A substance made up of atoms of two or more different elements joined by chemical bonds. It cannot be easily separated. A chemical reaction must occur to separate elements.
soluble
Able to be dissolved
Table Salt (Element, Compound, or Mixture)
Compound
Water (Element, Compound, or Mixture)
Compound
insoluble
Does not dissolve
Gold (Element, Compound, or Mixture)
Element
Hydrogen (Element, Compound, or Mixture)
Element
Explain why elements and compounds are both pure substances
Elements and compounds are both pure substances because they cannot be split apart by physical or mechanical methods.
Describe the difference between a Mechanical Mixture and a Solution using the particle theory
In a mechanical mixture the particles stay in separate groups, but in a solution the particles are distributed and spread around.
mixture
Matter with two or more types of particles (compounds or elements) that are physically combined, keep their original properties
Pizza (Element, Compound, or Mixture)
Mixture
Salt water (Element, Compound, or Mixture)
Mixture
salad (Element, Compound, or Mixture)
Mixture
Describe the difference between a Pure Substance and a Mixture using the particle theory
Pure Substance- is made up of one type of particle, while a mixture has more than one type of particle.
atom
Smallest particle of matter
solute
Substance being dissolved
Explain how to identify the solute and solvent in a mixture
The part that dissolves is the SOLUTE and it's the smaller part. The larger part, that the substance dissolves INTO is the solvent.
Explain why water is considered the Universal Solvent
There are so many substances that can dissolve into water to make a solution. (BUT... it will NOT dissolve everything...)
theory
When a hypothesis is supported through testing in many different experiments. (If there is evidence it can be disputed and disproven.)
homogeneous mixture
a mixture that is evenly mixed and you can't see the different parts, it all looks the same
heterogeneous mixture
a mixture that is not evenly mixed and you can see the different parts
Particle
a small piece of matter
solvent
causes a substance to dissolve
pure substance
made up of only one thing, can't be broken down into other substances
molecule
smallest unit of an element OR compound,which can be one or more similar atoms in an element OR one or more different atoms in a compound