Chemistry is an experimental science, therefore it is necessary to be able to work with units and measurements accurately.

Metric System
The metric system is based on prefixes that indicate a power of 10 with base units. 

SI System
The International System of units gives a standard unit for each type of measurement. 

There are also some important non-SI units as well.

Taking measurements
Measurements must be taken accurately.  Always write down one more decimal place than the instrument tells for certain—a “0” if it’s “one the line” and a “5” if it’s “between the lines.”

Significant Figures
The significant figure rules are to allow people to read data or calculations and know with what precision the data was taken.  The significant rules can be summarized in two rules: (1) If a decimal point is not present, count digits starting with the first the first non-zero number and ending with the last non-zero number; (2) If a decimal point is present anywhere in the number, start counting with the first non-zero number and continue until the end of the number.  Rules on how to perform calculations with significant figures will be given in a future tutorial.

Fundamental Constants
Several numbers are used throughout chemistry and are important to be familiar with.

Math skills are needed throughout a chemistry course.

Algebra
Algebra is used to solve equations by un-doing whatever is being done to an unknown variable. For example, if an equation has “x+2” then you would subtract “2” to solve for “x”.  Everything that is done to one side must be done to the other side of the equation as well.

Calculations with significant figures
You cannot become more precise after completing calculations than the original data was.  Therefore, it is important to write the answer with the correct number of significant figures.  When adding and subtracting with significant figures, you write the answer with the least number of decimal places that are in the problem.  When multiplying and dividing, write the answer with the least number of significant figures as is in the problems.

Scientific Notation
Scientific notation is a way of writing large or small numbers as a multiple of 10.  The decimal place is always placed behind the first non-zero number and the number of times the decimal point was moved to get there is used as the exponent of 10.  Positive exponents represent large numbers (>1) and negative exponents represent small numbers (<1).

There are when working with scientific notation numbers:

Logarithms
Logarithms are a way of counting in multiples of a base number.  If  then .  If no base is specified, it’s assumed to be 10. 

Calculator Tips

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The Metric and SI (International System) of units is used throughout chemistry.  The metric system is based on prefixes showing the power of 10 used with base units describing the quantity measured.

Chemistry is an experimental science; therefore it is necessary to take careful measurements.  Measurements should always include one more decimal place than the instrument indicates for certain—this last decimal place should be a “0” if the measurement is “on the line” and a “5” if the measurement is “in-between the lines.”  Most measurements are understood to be +/- 1 in the last decimal place, unless another uncertainty value is given with the measurement.

Once careful measurements are taken, the precision with which they were measured can not be heightened while doing calculations, nor should it be lost and allowed to become less precise.  Therefore, there are rules about counting “significant figures” which indicate which were measured for certain. 

Math skills are crucial throughout chemistry.  This tutorial reviews basic algebra needed in chemistry calculations.  Writing answers with the correct number of significant figures is taught, along with writing and reading numbers in scientific notation.  Performing calculations with exponents, including those in scientific notation, is illustrated.  Logarithms, both base 10 and natural logs, is taught.  The quadratic equation is demonstrated.  Finally, calculator survival tips are given to ensure the answer you type in what you intend.  All mathematical concepts are illustrated with chemistry applications—each one is actually used in chemistry calculations.

Specific Tutorial Features:

• Examples of the math techniques use chemistry applications

 Series Features:

• Concept map showing inter-connections of new concepts in this tutorial and those previously introduced.
• Definition slides introduce terms as they are needed.
• Visual representation of concepts
• Animated examples—worked out step by step
• A concise summary is given at the conclusion of the tutorial.

• The Metric and SI Systems
  • Metric prefixes
  • SI units
  • Common non-SI units
• Measurement and Uncertainty
  • Tools common in Chemistry Labs
  • Taking measurements
  • Uncertainty
• Lab Safety
• Common Lab Procedures
• Significant Figures
  • Why they’re used
  • How to count them
• Fundamental Constants used in Chemistry
• Algebra
  • Solving for a variable in addition/subtraction and multiplication/division
• Calculating with significant figures
  • Addition/subtraction
  • Multiplication/division
• Scientific Notation
  • Writing in scientific notation
  • Reading scientific notation
  • Calculations with scientific notation
• Logarithms
  • Logarithms with base 10
• Calculator tips
• Tips for Studying Chemistry