Midterm Flashcards
Physical change
A change in which the basic identity of the substance does not change Examples: • cutting wire • compressing a gas • distillation • dissolving sugar in water
Chemical change
When there is a change in the identities of the substances and new substances with different identities are formed Example: • rusting of iron • combustion of wood • ripening of a tomato • apple slices turning brown • decomposing of H2O2 into H2O and O2
Solution
There is no Tyndall Effect in solution. Light passes through solution, but the particles do not reflect light.
Suspension
A suspension can be filtered. Light does not filter through.
Colloid
While a suspension will separate out a colloid will not. Colloids can be distinguished from solutions using the Tyndall effect. Light passes through.
Element
One type of atom
Compound
Two or more different atoms bonded together
Mixture
Two or more compounds or elements mixed together
Allotropes
Two or more different molecular forms of the same element in the same physical state
Alloys
Mixtures composed of two or more elements at least of one which is metal
Homogeneous mixture
A mixture where the components that make up the mixture are uniformly distributed throughout the mixture.p
Heterogeneous mixture
A mixture where the components of the mixture are not uniform or have localized regions with different properties
Dalton
Said all matter is made of tiny indivisible particles called atoms, atoms of the same elements are identical, those of different atoms are different, atoms of different elements combine in whole number rations to form compounds, chemical reactions involve the rearrangement of atoms
Democritus
Originated the idea that all things were made of small pieces
Cathode ray tube
Tube used to pass electricity through a gas that is contained at a very low pressure