#chemistry tutorial

Welcome to new Chemistry Notes Info website

As everyone in the chemistry field will tell you, significant figures (or ‘sig figs’) are a necessary evil, and they help you to know the accuracy of your measurement. The more sig figs, the better the measurement.

They’re not too tricky once you get the hang of it, though. Let’s go through the basic rules, shall we?

How do I know if a digit is significant?

Every non-zero number is significant.

Example: 3.14 <-- this number has three significant figures

All digits in the mantissa of numbers written in scientific notation are significant.

Example: 1.11 x 10^5 <-- the 1.11 part is called the mantissa, and all three digits are significant.

Zeros can be tricky. Zeros are only significant if:

a) it is sandwiched between two other significant figures (ex: 303--the zero is significant; this also works with decimals: in 10.9 or 1.707 -- both of the zeros in each of these numbers is significant.)

b) it is after the decimal place and after another significant digit (ex: 0.990 the bolded zero is the significant zero. The other one is just a placeholder.)

c) it is otherwise indicated (usually by putting a . after it -- ex: 330. The zero is not significant.

So let’s cover some more examples:

910 <-- two significant figures, the zero is not significant

2007 <-- four significant figures, both zeros are significant because of the sandwich rule

0.235 <-- three significant figures; the leading zero is just a placeholder

123.678 <-- six significant figures

1.660 x 10^6 <-- four significant figures

Addition/Subtraction:

The key to remember is to always look at the lowest significant figure placeholder.

Example: 101; 10.1; 1.01; 0.101 -- the bolded digit is the lowest significant placeholder of each

This lowest placeholder is important, because the number with the smallest decimal place value is the determining number to tell you the place to which your final answer must be reported.

Example: 35.72 + 50.1 <-- the 50.2 has the lowest decimal place value: the tenths place. Therefore, your final answer should be recorded to the tenths place like so: 85.8

Example: 0.1000 + 0.59 = 0.69

Example: 520 + 13 = 530

Multiplication/Division:

This one is, in my opinion, easier. Simply count the number of significant figures in your multiplier or dividend, and the number with the least number of sig figs tells you how many sig figs should be in your final answer.

Example: 12.35(four sig figs) x 7.21(3 sig figs) <-- final answer should have three significant figures: 89.0

Example: 12(two sig figs) / 0.500(three sig figs) <-- final answer should have two significant figures: 24

Example: 101.25(five sig figs) * 21.0067(six sig figs) <-- final answer should have five significant figures: 2126.9

Practice makes perfect, so try some problems on your own.

Are you looking for chemistry tutorials? There are plenty on the web. Are they any good?

Here is how you can tell:

(1) Do these chemistry tutorials follow a learning system with a structure?

(2) Does the teaching style cater your learning preference?

(3) Do they have strong learning support on these chemistry tutorials?

One system and two words – Rapid Learning!

Instead of reading the textbook, how about watch a YouTube like movie with visualization and animation on screen and descriptive narration on the background? Coupling with smart teaching, rapid learning enables you to master chemistry visually and rapidly rather than getting confused with reading on textbooks.

How about learning chemistry visually in 24 hours?

Is your current old style learning method helping you to learn the way you expected? There is an alternative to traditional chemistry learning, that is Rich-Media Learning.

This is to use the multi-modal rich learning via enhanced visualization, animation and expert narration, along with the focus on core concepts and problem solving skills.

Chemistry for many is not easy to understand and get the core subject, but it is so important that you have to pass it in order to move forward with your college education.

What is the unique about this subject? Chemistry is a visual science, what better way to master it than via visual learning! Use your two most powerful senses – visual and auditory. Visualize the chemistry at the molecular level.

The rich-media General Chemistry Tutorial Series by Rapid Learning Center is a break-through learning system with scientific teaching method coupling with rich-media visualization and clear narration. In chemistry, it breaks down the entire course into 24 chapters, one chapter at a time, and one hour per chapter in total of 24 hours.

  Here is the step by step to your general chemistry success:

Step 1:  Study all the necessary core concepts and learn how to solve the related problems step by step via rich-media video tutorials.

Step 2:  Practice the problem solving with the feedback-based interactive drills.

Step 3:  Super Review the summary cheat sheet for all the key concepts and formulas. Put them into your memory system for easy retrieval in your general chemistry exam.