Coachkchem.weebly.com



Notes: Scientific Notation, Rounding, and Significant figuresScientific Notation - Can be used to express any number between 1 and 9 multiplied by 10 raised to a power.-Example: 4.6 x1023 or 4.5 E 23Recognizing Significant figuresRule 1: All non-zero digits (1 through 9) are significant Rule 2: Zeros between non-zero digits are significant- 2034 has 4 significant figures- 3.0005 has 5 significant figuresRule 3: Any zeros to the left of the first non-zero digit are NOT significant (called leading zeros)- 0.005 has 1 significant figure- 0.036 has 2 significant figuresRule 4: Any zeros at the end of a number that contains a decimal point ARE significant (called trailing zeros)- 3.0 has 2 significant figures- 0.0250 has 3 significant figures- 800. has 3 significant figures- 800.0 has 4 significant figuresRule 5: Zeros at the end of a whole number that does not contain a decimal point are not significant. - 800 has 1 significant figure- 102,000 has 3 significant figuresRule 6: When numbers are in scientific notation, disregard the power of ten and use the above rules on the decimal number only.- 3.8 x 1015 has 2 significant figures- 3.08 x 1015 has 3 significant figuresAdding and subtracting scientific notation- Exponents must be the same.-When exponents are the same add or subtract the coefficients-Example: 7.35 x104 + 2.43 x104 = 9.78 x104What happens when they are not the same?-Example:2.840 x104 + 3.146 x103 + 1.50 x102 2.840 x104 + 0.3146 x104 + 0.0150 x104= 3.17 x104- When you add or subtract measurements, the answer must have the same number of digits to the right of the decimal as the original value having the fewest number of digits to the right of the decimal.-Example:5.623 + 2.72 + 4.0 = 12.343 12.3Multiplication and division- Exponents do not have to be the same.- For multiplication, multiply the coefficients and add the exponents.-Example:2 x 103 x 3 x 102 = 6 x 105- For division, divide the coefficients and subtract the exponents.-Example:9 x 108 / 3 x 104 = 3 x 104- When you multiply or divide numbers, your answer must have the same number or significant figures as the measurement with the fewest significant figures.-Example: 2.45 x 3.4 = 8.33 8.3Rounding Numbers:Rule 1: If the digit to the right of the last significant figure is less than 5, do not change the last significant figure. - 2.531 2.53Rule 2: If the digit to the right of the last significant figure is greater than 5, round up the last significant figure. - 2.5351 2.54 ................
................

In order to avoid copyright disputes, this page is only a partial summary.

Google Online Preview   Download