Name ______Date ______Period ______# _____

Second Nine Weeks Study Guide

Concepts Include:

·  Ion Charges and Valence Electrons

·  Balancing Equations

·  Ionic and Covalent Compounds

·  Endothermic and Exothermic Reactions

·  Acids, Bases, and pH

·  Phase Changes

·  Radioactivity

Ion Charges & Number of Valence Electrons (Ch. 19 & 22)

You should know how to use the periodic table to predict the oxidation numbers (ion charges) and number of valence electrons of elements in columns 1, 2, 13, 14, 15, 16, 17, and 18.

sPractice Problems

Which elements would be most likely to form a compound, in a 1:1 ratio, with oxygen? ______

Which elements would be most likely to form a compound, in a 1:1 ratio, with sodium? ______

Element / # of Valence Electrons / Ion Charge
Oxygen
Calcium
Neon
Sodium
Nitrogen
Aluminum
Fluorine
Silicon

Balancing Equations

You should know how to put in coefficients to balance chemical equations.

sPractice Problems—balance the following chemical equations

Na + Cl2 à NaCl CH4 + O2 à CO2 + H2O P + O2 à P4O1

Ionic and Covalent Compounds

You should know the following information about ionic and covalent compounds

Formula / Ionic or Covalent? / High or low melting point? / Conduct electricity or not?
NaHCO3 / /
H2O2
NH3 / / /
KCl / / /
CH4 / / /

Endothermic and Exothermic Reactions (Ch. 23)

You should know the difference between endothermic and exothermic reactions.

sPractice Problems

Define endothermic

Define exothermic

Classify each reaction as endothermic or exothermic and EXPLAIN WHY you made that choice:

·  Melting ice

·  Freezing water

·  Boiling water

·  Cooking an egg

·  Burning coal

Acids, Bases, and pH (Ch. 23-24)

You should know the information from your notes on the pH scale. You need to know the range of the pH scale, which numbers correspond to acids, bases, and neutral pH, and how adding acid to a solution will lower the pH, while adding a base will increase the pH. s

Acids / Bases
pH range
What color litmus turns
What they taste like
Ions present
Range for Strong
Range for Weak

Phase Changes (Ch. 9 & 18)

You should know the information from your notes before break regarding states of matter. Specifically, you need to know that temperature does not increase during a phase change; energy is used to change the state of matter (i.e. melting, boiling) rather than increasing the temperature of the substance. When graphed, this is seen as a line with no slope. You should also know that the greater the temperature of a substance, the faster the molecules are moving in that substance.

Draw the molecule arrangement for the following phases of matter. s

SOLID LIQUID GAS

Radioactivity (Ch. 25)

You should know that elements are radioactive when their nuclei are unstable, that heavier elements are more likely to be radioactive (all elements with an atomic number above 83 are radioactive), and that there are three types of radioactivity: alpha particles, beta particles, and gamma rays.

sWhich is the most likely to be radioactive? Beryllium (Be), Polonium (Po), or Osmium (Os)

Alpha Particles / Beta Particles / Gamma Rays
What are they made of?
What stops them?
What happens to the atom when it loses one?