Chemistry Mysteries: Scientific Notation

Scientific Notation: used to express very large or very small numbers.
Any number will be between 1 and 10, multiplied by a power of 10.

Ex/ 3489=3.489×10³When you move decimal to the left - positive exponent (examples: 10⁶)

0.3489=3.489×10^-2

When move decimal to the right - negative exponent (example: 10^-4)

Ex/ 465          4.65 x 10²

                    = 465
3489=3.489
0.3489=3.489                    =4.65 x 10^-2

                    = 0.0465

Adding / Subtracting
When adding or subtracting, change the scientifc notations into standard form and add or subtract
                       ( 5 x 10² ) + ( 1 x 10³ )
                    = 500 + 1000
                    = 1500
Then, change the number back into scientific notation
                    = 1.5 x 10³

Or, change the power of 10 so that they are the same and add or subtract the number (between 1-10) and keep the power of 10 the same

Example: (7×10⁶) + (3×10⁵)

= (7×10⁶) + (0.3×10⁶)

= 7.3×10⁶

Multiplying / Dividing
Multiply or divide the number between 1-10 first, then multiply or divide the power of 10


( 2 x 10³ ) ÷(8 x 10² )
                    = 2÷8= 0.25
                    = 10³÷10²
                    = 0.25×10¹
= 2.5

Rounding: Avoid rounding in the middle of a question. Round ONLY at the final answer.

Scientific Notation on Calculator

If we want to express 2×10⁶ on the calculator, then we can press 2 then the EXP or ×10^x button and then 6. This button will save time and avoid making mistakes.

Matter
Matter is anything that has mass and occupies space.