Scientific-notation-significant-figures-conversion-of-units-Q1_LP1.pptx

scientific notation

1. A lecture on Importance of Chemistry Scientific Notation Significant Figure Conversion of Units Advanced Chemistry Chemacademy Presents !!!

2. Chemistry Branch of science that deals with the study of matter, its composition, properties, changes it undergoes, and laws governing the changes.

3. Chemistry IS DIVIDED IN 5 AREAS ORGANIC CHEMISTRY study of the structure, properties, and preparation of chemical compounds that consist primarily of carbon and hydrogen. INORGANIC CHEMISTRY study of the properties and behavior of inorganic compounds. ANALYTICAL CHEMISTRY involves the qualitative and quantitative determination of the chemical components of substances. PHYSICAL CHEMISTRY study the rate of a chemical reaction, the interaction of molecules with radiation, and the calculation of structures and properties. BIOCHEMISTRY the study of chemical reactions or processes that take place in living things.

4. Importance of chemistry to other fields of science

5. Importance of chemistry in daily living

6. scientific notation is a way of expressing numbers that are too large or too small (usually would result in a long string of digits) to be conveniently written in decimal form.

7. Rules in writing scientific notation 1. Move the decimal place to the left or right so that there will be a single non-zero digit to its left. to create a new number from 1 up to 10. For example, in the figure 312,000,000,000 because it’s a whole number, the decimal point is understood to be at the end of the number, 312,000,000,000. So, c = 3.12

8. 2. Determine the exponent, which is the number of times you moved the decimal. In this example, 3 12,000,000,000 , you moved the decimal 11 times Hence, 3.12 x 10 11 3. To determine the sign of exponent, look for the direction of movement from original decimal point to its new position. If the direction is going to the left, the sign is positive (+), if its going to the right the sign is negative (-). Therefore, the scientific notation of 312,000,000,000 is 3.12 x 10 +11

9. MULTIPLICATION DIVISION ADDITION SUBTRACTION Multiply the coefficients and add the exponent. Divide the coefficient then subtract the exponent of the denominator from the numerator. Make the exponents the same. The decimal points must be aligned. Add the numbers. Copy the exponent. Make the exponents the same. The decimal points must be aligned. Subtract the numbers. Copy the exponent. Example: 3.0 x 10 4 X 2.0 x 10 2 (3.0 x 2.0) x 10 4+2 6.0 x 10 6   3.0 x 10 4 ÷ 2.0 x 10 2   3.0/2.0 x 10 4-2 1.5 x 10 2   5.40 x 10 3 + 6.0 x 10 2 5.40 x 10 3 + 0. 60 x 10 3 6.00 x 10 3 8.87 × 10 8 – 9.3 × 10 7 88.7 × 107 – 9.3 × 10 7 79.4 × 10 7 Simplify: move decimal point to the left Final Answer : 6.0 x 10 6 Final Answer : 1.5 x 10 2 Final Answer : 6.00 x 10 3 Final Answer : 7.94 × 10 8

10. Rules in determining significant figure/s 1. non-zero digits are always significant 2. any zeros between two significant digits are significant 3. a final zero or trailing zeros in the decimal portion only are significant 4. a zero used to fix a decimal point is never significant. 5. trailing zeros in a whole number with no decimal shown are not significant. 

11. Appreciation of zeros ast significant or not

12. Mathematical operation involving significant figures

13. Conversion of units Dimensional analysis (also called factor-label method or the unit factor method ) is a problem-solving method that uses the fact that any number or expression can be multiplied by one without changing its value. It is a useful technique. The only danger is that you may end up thinking that chemistry is simply a math problem - which it definitely is not.

14. Sample problem using dimensional method of conversion Ana weighs 55 kilograms. Determine her weight in grams. Given: weight = 55 kgs required= weight in grams Solution: 55 kgs x = 55 000 grams  

15. Converting temperature and density calculation