Why should You learn Chemistry? Required –Pharmacists –Doctors –Dentists –Chem Engineer, etc. Need it to pass Standardized Exams, Boards, etc. –MCAT –PCAT –DAT –OAT, etc Understanding of Nature –Drug Design: Manipulate molecules for better medicine –Better utilize Energy: Manipulate molecules for better fuels –Better understand Life: Biochemistry/Molecular Biology –Create better technology

Outline of presentation What is Chemistry? Analytical Chemistry What is in a sample? How much is present? Biochemistry- study of life’s chemistry Inorganic Chemistry- all other elements except carbon Separation Science Organic chemistry- study of carbon compounds Physical Chemistry- study of chemical events based on natural physical phenomenom

Organic Chemistry is the study of compounds that consist of carbon atoms

What is so special about Carbon? Interesting facts: –46 million chemical compounds are known in nature. –99% of them contain carbon (thus organic) –Why??

Biochemistry “ What are the unique chemical foundations of all life and what is different”

Why should you Learn Biological Chemistry: Drug Design Sildenafil What knowledge is required for drug design? Know structures of protein targets in the body Biochemistry Molecular Biology Know how to manipulate organic molecules to create new compounds with specific properties Organic chemistry Chemical Synthesis

Analytical Chemistry: Science of Chemical Analysis

Careers in Chemistry Chemist/Biochemist Chemical Engineer Industrial Chemist Chemical Technician B.S. (4yr), M.S. (6-7yr), Ph.D. (8-12 yr)

Matter and Measurement By Doba D. Jackson, Ph.D. Associate Professor of Chemistry & Biochemistry Huntingdon College

Scientific Method

Why use the scientific method? - Ensures the accuracy of information obtained. - Minimize the influence of bias or prejudice. -Problems in Scientific method -Failure to rule out all information that do not fit the hypothesis - Failure to account for errors in the experimentation

Matter and Measurement Learning outcomes 1.Describe the different elements and states of matter and their general physical properties 2.Distinguish between different classes of matter. 3.Distinguish between Physical processes and chemical processes 4.Distinguish between exact and uncertainty in numbers, also to express numbers with proper significant figures.

Chemistry and the Elements

Elements and the Periodic Table Main Groups columns 1A – 2A (2 groups) columns 3A – 8A (6 groups) Transition Metals: 3B–2B (8 groups, 10 columns) Inner Transition Metals: 14 groups; 3B - 4B lanthanides actinides

Some Chemical Properties of the Elements Property: Any characteristic that can be used to describe or identify matter. Intensive Properties: Do not depend on sample size. temperature melting point Extensive Properties: Do depend on sample size. length volume

Properties of the Elements Physical Properties: Characteristics that do not involve a change in a sample’s chemical makeup. Chemical Properties: Characteristics that do involve a change in a sample’s chemical makeup.

Some Chemical Properties of Alkali Metals Alkali Metals

Some Chemical Properties of Alkaline Earth Metals Alkaline Earth Metals

Some Chemical Properties of the Halogens Halogens

Some Chemical Properties of the Noble Gases Noble Gases

Some Chemical Properties of the Elements Metals Nonmetals

Some Chemical Properties of the Semimetals (Metaloids) Semimetals

Experimentation and Measurement All other units are derived from these fundamental units.

Mass and its Measurement Mass: Amount of matter in an object. Matter: Describes anything with a physical presence—anything you can touch, taste, or smell. Weight: Measures the force with which gravity pulls on an object.

Mass and Its Measurement

Temperature and Its Measurement (°F - 32 °F) 5 °C 9 °F °C =°C + 32 °F 9 °F 5 °C °F = K = °C Fahrenheit to Celsius Celsius to Fahrenheit Celsius to Kelvin

Derived Units: Volume and Its Measurement

Volume is derived from the Length, Width and Height

Derived Units: Energy and Its Measurement Energy: Capacity to supply heat or do work. Kinetic Energy (E K ): The energy or motion. Potential Energy (E P ): Stored energy. Units: 1 Cal = 1000 cal = 1 kcal = J 1 calorie (cal) = J (joule)

Accuracy, Precision, and Significant Figures Measured quantities: A number obtained by measurement using a specific instrument. Measured quantities have a limited number of significant figures. Significant figures: The total number of digits recorded in a measured or calculated quantity. They come from uncertainty in any measurement. Generally the last digit in a reported measurement is uncertain (estimated). Exact numbers: typically relationships (7 days in a week, 30 students in a class, etc.) effectively have an infinite number of significant figures.

Accuracy, Precision, and Significant Figures length = 1.74 cm cm 1.7 cm < length < 1.8 cm

Measured quantities are always have a limit of known digits Accuracy: How close to the true value a given measurement is. Percent error Average Precision: How well a number of independent measurements agree with each other. Standard Deviation Least squares fit analysis

Accuracy and Precision Measurement # Bathroom Scale Lab Balance Analytical Balance 10.0 kg54.4 g g 20.0 kg54.5 g g 30.1 kg54.3 g g (average)(0.03 kg)(54.4 g)( g) Poor Accuracy Poor Precision Mass of a Tennis Ball

Accuracy and Precision Measurement # Bathroom Scale Lab Balance Analytical Balance 10.0 kg54.4 g g 20.0 kg54.5 g g 30.1 kg54.3 g g (average)(0.03 kg)(54.4 g)( g) Good Accuracy Poor Precision Mass of a Tennis Ball

Accuracy and Precision Measurement # Bathroom Scale Lab Balance Analytical Balance 10.0 kg54.4 g g 20.0 kg54.5 g g 30.1 kg54.3 g g (average)(0.03 kg)(54.4 g)( g) Good Accuracy Good Precision Mass of a Tennis Ball

Significant Figures Rules for counting significant figures: 1.Zeros in the middle of a number are like any other digit; they are always significant. 2.Zeros at the beginning of a number are not significant; they act only to locate the decimal point. 3.Zeros at the end of a number and after the decimal point are always significant. 4.Zeros at the end of a number and after the decimal point may or may not be significant. 34,200 m5 SF K5 SF g3 SF (or 6.61 x g) cm4 SF

State the number of significant figures in each of the following numbers a).0312 b) c)312 d)3.12 x

Rounding Numbers Math rules for keeping track of significant figures: Multiplication or division: The answer can’t have more significant figures than any of the original numbers gal 278 mi = 23.8 mi/gal (mpg) 4 SF 3 SF

Rounding Numbers Math rules for keeping track of significant figures: Multiplication or division: The answer can’t have more significant figures than any of the original numbers. Addition or subtraction: The answer can’t have more digits to the right of the decimal point than any of the original numbers decimal places 5 decimal places 2 decimal places = ?

Calculations: Converting from One Unit to Another Dimensional analysis: A method that uses a conversion factor to convert a quantity expressed with one unit to an equivalent quantity with a different unit. Conversion factor: States the relationship between two different units.

Calculations: Converting from One Unit to Another 1 m = in Conversion factor: Relationship: 1 m in or in 1 m converts m to in converts in to m

Calculations: Converting from One Unit to Another in 1 m 69.5 in = 1.77 mx equivalent quantitystarting quantity conversion factor Correct Method

Calculations: Converting from One Unit to Another 1 m in 69.5 in = 2740 in 2 /mx ??starting quantity conversion factor Incorrect Method