10 Chem Chapter 2 Energy

Energy -

Energy is the capacity to do work or produce heat

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Kinetic Energy is energy of motion

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Potential Energy is stored energy

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Electrical Energy is energy that exists when objects with different electrical charges are separated

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Chemical Potential Energy is energy that exists in chemicals (fuels)

Measuring Energy -

Measured in Joules

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1 cal = 4.184 J

Temperature: -

The SI unit is Kelvin

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C = K – 273

Elements and Compounds -

Elements are substances that cannot be separated into simpler substances by chemical change

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Compounds are two or more elements combined by a chemical reaction

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Elements and compounds are both pure substances.

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Compounds and elements can be separated from electrolysis that tears apart chemicals with electricity

Mixtures -

A mixture is a blend of two or more pure substances

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A heterogeneous mixture is a mixture that has visibly different parts

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A homogeneous mixture is a mixture that has no visibly different parts

In order to separate mixtures: -

Distillation takes advantage of differences in boiling points

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Crystallization uses evaporation to separate mixtures

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Chromatography allows solution to flow along stationary substances to separate its parts. Eventually a pattern shows the separated pigments