CHM135H1 Study Guide - Final Guide: Kinetic Theory Of Gases, Covalent Radius, Black-Body Radiation
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CHEM139
Exam notes on chapters 1,2,3,5,7,8
Chapter 1
-Chemistry origins from 3 overlapping conditions: Alchemy, Medicine and Technology.
-Debate of Phlogiston in combustion, Lavoisier discovered oxygen and metal oxides and proved
Phlogiston theory wrong.
-Convert to appropriate units before solving a problem
-Density= Mass/Volume (g/L) (g/cm^3)
-Temperature and Heat are not the same!
> Temp is how hot or cold one object is relative to the other. (K=C +273.1)
>Heat is the energy which flows from the object with the higher temp to one that has a lower one.
Chapter 2
-Matter can be classified based on composition: Elements, Compounds, and Mixtures.
-Elements and compounds are substances. (substance= matter whose composition is fixed)
-Elements consist of only one atom, compounds consist of 2 or more elements that are chemically
bonded, and mixtures consist of two or more substances.
-The law of conservation of mass: Mass is conserved because matter cannot be created or destroyed.
-Law of definite composition: No matter what its source, a particular compound of the same element in
the same parts (fractions) by mass. Fraction by mass is how much each element contributes to weight.
-The law of multiple proportions states that, in different compounds of the same elements, the masses
of one element that combine with a fixed mass of the other can be expressed as a ratio of small whole
numbers. This is because different numbers of B atoms combine with each A atom in different
compounds.
- Dalton’s atomic theory explained mass laws by proposing that all matter consisted of indivisible,
unchangeable atoms of fixed, unique mass.
-Mass is conserved because the elements retain their identities but are combined differently.
-Problems with Daltons model were later solved. Cathode Rays showed negative particles existed in all
matter. Charge and mass of electrons measured. Rutherford proposed of a tiny positive nucleus
surrounded by electrons.
Atomic number=#of Protons Mass Number=Protons + Neutrons #of Neutrons= Mass #-Atomic#
Ionic bonds-transferring electrons