Unit 4 conceptual chem

polyatomic ion

group of covalently bonded atoms with a charge

Polyatomic ion examples

Phosphate: PO43-
Nitrate: NO31-

Where are atoms with positive oxidation numbers/ charges written?

First

How to neutralize a negative charge?

Use a positive charge

Oxidation number of transition elements

They can have multiple

diatomic elements

2 atoms covalently bonded together

Organic

contain carbon and derived from organisms

Inorganic

Does not contain carbon

organic compound examples

CH4: methane
C6H12O6: glucose (sugar)

inorganic examples

O2, H2O

Hydrocarbons

Compounds composed of only carbon and hydrogen

How many bonds can carbon form

4 bonds

metal ions

Lose electrons
Positive charge (cation)

nonmetal ions

Gain electrons
Negative charge (anion)

Electronegativity

A measure of the ability of an atom in a chemical compound to attract electrons

Ionic bonds

Attraction between ions

Binary ionic compounds

Ionic compounds with two elements

oxidation number

Charge
Positive or negative number that indicates how many electrons an atom has gained, lost, or shared to become stable

molecular substance definition

Made of covalently bonded elements
Share electrons
Between nonmetals

Examples of molecular substances

Water, carbon dioxide, chlorine gas

Molecular properties

Nonmetals
Usually gas or Solid
liquid
Lower Interparticle force
Covalent
Variable solubility
Nonconductive

Ionic properties

Metal + nonmetal
Higher force Ionic
High solubility
Conductive

Compound

Two or more elements chemically bonded together
Fixed ratio

Examples of compounds

NaCl: sodium chloride
CO2: carbon dioxide
H2O: water

Reactants

Substances that exist before the reaction

Products

Exist after the reaction

What part of the atom is involved in forming compounds?

Electron cloud only (not the nucleus)

What do valence electrons determine?

the chemical properties of an element

Noble gases are

Unreactive
Do not form compounds
Have a full number of valence electrons

octet rule

Atoms achieve stability by having 8 valence electrons
Gain/lose or share

How do atoms achieve stability?

by losing, gaining, or sharing electrons, filing their outermost shell to its prescribed number of electrons

Whats an atom's charge if it gains an electron

Negative

Whats an atom's charge if it loses an electron

Positive

Cations

Ions with a positive charge
Lose electrons

Anions

Ions with a negative charge
Gain electrons

Electronegativity

A measure of the ability of an atom in a chemical compound to attract electrons

ionic bonding

Bond between a cation and an anion
Between a metal and a nonmetal

sharing electrons

Two atoms come close together and their electron clouds overlap
share a pair of electrons
Between nonmetals

covalent bonding

Share electrons
Spend time around each atom

Nonpolar

equally sharing of electrons

polar

Unequal sharing of electrons

Interparticle forces

Forces of attraction between particles
Greater the attraction -> more solid state

chemical formula

shows the elements in the compound and the ratio of atoms