Site hosted by Build your free website today!

Chemistry 1411-Donna McNeely

Thank You for visiting this Chemistry web site. I hope you enjoy the homework and essays that are to follow within the next few months. Thanx much, Donna

Chemistry Post-Lecture Assignment

1) Read 1.1-1.3 and write a small summary. This is a basic introduction to what we will be learning this semester. I gives us the basic knowledge that we will need like definitions for matter, mass, element and chemical formula.
2) Get familiar with the following concepts (I.e. define).
A) Chemical Property- can be observed when a substance undergoes a chemical reaction. Like butane burning when oxygen and a spark are present.
Physical Property - characteristic properties of a substance, by itself (I.e. color, density, boiling/melting points.)
B) Define elements/compounds/mixtures. elements- are substances that contain only one kind of atom. (helium or carbon)
compounds-contain more than one element combined in fixed proportions. (water or table salt) mixtures- have different compositions from sample to sample and varying properties. (coffee)
C) What are the atomic symbols and names for H through Ar?
H- hydrogen B- boron O-oxygen Na- sodium Si- silicon He- helium C- carbon F-florine Mg- magnesium P-phosphorus Li- lithium N-nitrogen Cl- chlorine Al-Aluminum S-sulfur Be- beryllium Ne-neon Ar- argon
Q1) What are Aluminums physical and chemical properties?
Physically it is silver, malleable, and conducts electricity. Chemically it reacts with acids.
Q2) Is aluminum a pure substance or a mixture?
It is pure because it has only one type of atom and is listed on the periodic table.
D) What are isotopes?
atoms with the same atomic # but different numbers of neutrons.
E) Define atomic mass/ number / structure.
Atomic mass- the total weight of an atom measured by the total of protons and neutrons in the nucleus.
Atomic number- each element has been assigned a number that describes the number of protons in the nucleus of an atom of that element. (I.e. hydrogen is 1 and carbon is 6)
Atomic structure- describes the arrangement of atoms of a substance in a 3 dimensional space.