LOGO Course lecturer : Jasmin Šutković 2th March 2016 Chemistry - SPRING 2016 Lecture 1: Introduction to Chemistry

Grading criteria Link for the book: My IUS account: Quizzes(2x) 2 x 10% = 20% Midterm exam Project (group project) Homework’s (5x) 20% 10% 5% Attendance (Required, more than 70%) 5% Final exam 40% Total 100%

Book

Contents International University of Sarajevo 1. Chemistry in our lives 2. Chemistry and Chemicals 3. Scientific Method Next week: Chemistry and measurement Matter and Energy

Chemistry of our lives  Chemistry is the study of properties of substances and how they react with one another.  It is an experimental science based of the scientific method!  Hunderds of materials that we use EVERY DAY, directly and indirectly, are the products of chemical reseacrh.  For example: Plastics, Computer Chips, paper, fuels, cement, ceramics, sollar cells, Cosmetics and so on  WE NEED CHEMISTRY TO UNDERSTAND OUR ENVIRONMENT!! International University of Sarajevo Why we study Chemistry ?:

Important chemistry processess in our life !  Digestion..  Cooking..  When you write with ink on paper..!  Steel is 94% iron and 6% carbon. The carbon forms complex bonds making steel so strong that you can bend an iron crowbar, but not a steel one.  ANYTHING that burns is undergoing a chemical reaction and almost always creates some form of carbon as waste.

Figure1. Chemistry in every day life

Forensic scientist…

Hemoglobin Hemoglobin transports oxygen to the tissues and carbon dioxide to the lungs.

Chemistry  Chemistry is the study of the composition, structure, properties, and reactions of matter.  Matter is another word for all the substances that make up our world.

 Chemistry is not done only in lab…  Actually, chemistry happens all around you every day and has an impact on everything you use and do.  You are doing chemistry when you cook food, add bleach to your laundry, or start your car.

Antacid tablets undergo a chemical  A chemical reaction has taken place when silver tarnishes or an antacid tablet fizzes when dropped into water

Chemicals  A chemical is a substance that always has the same composition and properties wherever it is found.  All the things you see around you are composed of one or more chemicals.

Scientific method…

Scientific method  Help to explain how scientists think….

Approach …  1.Observations- look around you and ask yourself question !!  2. Hypothesis. Propose a hypothesis, which states a possible explanation of the observations.  The hypothesis must be stated in such a way that it can be tested by experiments.  3. Experiments.  4. Conclusion. When the results of the experiments are analyzed, a conclusion is made as to whether the hypothesis is true or false.

Scientific method cont…  If we gather enough data about our subject we will be able to form a HYPOTHESIS.  Hypothesis is a proposed explanation for an observation, phenomenon, or scientific problem that can be tested by further investigation!  To test the hypothesis we perform EXPERIMENTS.If the experiments support the hypothesis we will perform another experiments(under various conditions) to verify our statement.  After many confirmed experiments( the results are reproducible) we can CONCLUDE and state a LAW or Scientific law.  A law simply says what happens but doesn't explain it (why this happens).

Scientific method cont….  Once a Law has been formulated, scientist try to develop a THEORY (unifying principle) that explains the law based on experimental methods( why nature behaved as it does ).  The theory can develop by time because new facts may arise. Scientific method

 See you next Monday …