Scientific Notation, Significant Figures, and Density
Scientific Notation
Scientific notation is a way to convert a big number into a decimal equation. Example: 76,000,000 Move the decimal 7 spaces over to the left making the number 7.6 x 10^7 .00076543 Move the decimal over 4 spaces to the right and make the exponent negative making the number 7.6543 x 10^-4 Basic Conversion Chart
1M = 1x10^6 1k = 1000 1d = 1x10^-1 1c = 1x10^-2 1m = 1x10^-3 1u = 1x10^-6 1n = 1x10^-9 |
Significant Figures
Significant figures are each of the digits of a number that are used to express it to the required degree beginning from the first nonzero digit. 3 Types of Significant Figures: 1.) leading zeros- 0.01234 4 significant figures 2.) captive zeros- 5.07 3 significant figures 5,007 4 significant figures 3.) tailing zeros- not significant 300 1 significant figure significant 300. 3 significant figures Adding/Subtracting Significant Figures: Find the number with the least amount of decimal places then find the smallest amount of significant figures Examples: 3.657 1.30000 + 5.4100 10.36700 3.657 has the least amount of decimal spaces and it has 4 significant figures making the answer 1.037 x 10^1 Multiplying/Dividing Significant Figures: Find the significant figures of each number and take the smallest amount of significant figures Examples: 4.56x2.652 = 12.09312 4.56 has 3 significant figures and 2.652 has 4 significant figures because 3 is smaller than 4, the answer is 1.21x10^1 |
Density
Density equals mass over volume D=mass/volume It can be measured in g/cm^3 of g/mL Example: The element bromine at room temperature is a liquid with a density of 3.12 g/mL. Calculate the mass of 125 mL of bromine. What volume does 85.0 g of bromine occupy? 125 g/mL x 3.12 g = 3.90x10^2 1 mL Conversion of Temperature Fahrenheit = 1.80xC+32 Kelvin = 273.15+C |
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