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Flashcards in Lecture 2 Deck (20):
1

atom

The smallest unit of matter

2

chemical bond

An attraction between two atoms, resulting from a sharing of outer shell electrons or the presence of opposite charges on the atoms. The bonded atoms gain complete outer electron shells.

3

chemical reaction

The making and breaking of chemical bonds, leading to changes in the composition of matter

4

compound

A substance consisting of 2 or more *different* elements.

5

covalent bond

A type of strong (the strongest) chemical bond in which 2 atoms share one or more pairs of valence electrons.

6

electron shell

An energy level of electrons at a characteristic average distance from the nucleus of an atom
Note: The first shell has 1 orbital. The rest have 2.

7

electron

Sub-atomic particle with a single neg. charge.

8

element

Any substance that can't be broken down to any other substance by chemical reactions.

9

hydrogen bond

The weakest chemical bond. Happens when polar covalent bonds are attracted to each other.

10

ion

Atom/atoms that have gained or lost an electron resulting in a pos./neg. charge.

11

ionic bond

Middle strength chemical bond. Results from attraction of oppositely charged ions.

12

isotope

One of several atomic forms of an element. Same number of protons but different neutrons, thus differeing in atomic mass

13

molecular formula

The recipe of a molecule

14

molecule

Two or more atoms held together by covalent bonds.

15

neutron

Sub-atomic particle with no electrical charge. Found in nucleus of atom.

16

product

A material resulting from a chemical reaction

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proton

Sub-atomic particle with a single pos. charge. Found in the nucleus.

18

reactant

A starting material in a chemical reaction

19

structural formula

A diagram of an atom/molecule showing the distribution of electrons.

20

valence

The bonding capacity of a given atom. The number of covalent bonds an atom can form usually equals the number of unpaired electrons in it's outermost (valence) shell.