Chemistry Warm-Up: Elements, Compounds, and Bonds

1. 9-24 Warm Up PUMA, KORINA and whoever else…set your experiment up!!! Bennie, Hagles, Millers, Grassland --- SODA??? Finish your lab set up!!! Everyone else – get out your worksheet packet You have until 8:30 to finish pages 1-6

2. Composition of Matter - Ch 2 Hakim

3. Terms… • Matter – • Anything that occupies space and has mass • What is the difference between mass and weight? • Mass – • Amount of matter something has • What is weight? • Measure of the pull of gravity on an object

4. Elements • Substances that cannot be broken into simpler kinds of matter • Atom – • Simplest particle of an element that retains the properties of that element • Nucleus - • Contains protons and neutron • Makes up most of the mass

5. Proton • Positively charged particles in nucleus • Electron • Negatively charged particles that orbit the nucleus • Neutron • Neutral particle in the nucleus

6. Atomic Number • Number of protons • Mass Number • Number of protons and neutrons in an atom • Isotopes • Atoms can have different number of neutrons • EX: Carbon-12, Carbon-13 & Carbon-14 • So the number of isotopes are averaged and that is the mass number on the periodic table • So the majority of Carbon (~99%) has ______ neutrons? • 6

7. 9-25 Warm up • What is the difference between atomic number and mass number? • Water your plants (not too much!) Water is in water bottles up front. • Get out the worksheet pages 1-6…put your name on it…tear off back sheet…pass pages forward!!! • Also, hand in your warm ups!

8. Compounds - • Atoms of two or more elements • Elements usually bond to become more stable • Energy Levels • First energy level can hold 2 electrons • Second energy level can hold 8 electrons • Third energy level can hold 18 electrons • Atoms want their energy levels to be full so they are more stable • http://my.hrw.com/sh/hm2/0030724872/student/ch02/sec01/qc07/hm202_01_q07fs.htm • Draw this….

9. How many electrons in… • How many does it need to become stable? • How many electrons in… • And how many needed to be stable?

10. 9-28 Warm Up • How many electrons can carbon accept in it’s 2nd energy orbital? • Check your plants for growth and water them if the soil is no longer moist.

11. Carbon = Organic Chem. • Carbon bonds readily with other elements…why do you think this happens? • B/c carbon has only4 e- in it’s outer orbital,meaning it readily accepts e- from otherelements

13. Compound • Aspirin: • http://my.hrw.com/sh/hm2/0030724872/student/ch02/sec01/qc08/hm202_01_q08fs.htm

14. Sharing 1 electron = single bond Sharing 2 electrons= double bond Sharing 3 electrons= triple bond • Draw…

16. Bonds • Covalent Bond – • Two atoms share electrons • Water • http://my.hrw.com/sh/hm2/0030724872/student/ch02/sec01/qc09/hm202_01_q09fs.htm

17. Bonds • Ions – • Atom / molecule with a charge ( + or - ) • Elements give / take electrons to become more stable • Ionic Bond – • Charged ions attracting each other • http://my.hrw.com/sh/hm2/0030724872/student/ch02/sec01/qc12/hm202_01_q12fs.htm

19. 9-29 Warm Up • What is the difference between a covalent bond and an ionic bond?

20. Another example of an ionic bond…

21. States of Matter • Solid • Liquid • Gas • Which state has the least energy? The most? • Solid  Liquid  Gas • Which state occupies the most volume? • Which take shape of container?

22. Activation Energy • Activation Energy – • Most rxns need energy input to begin • Enzyme - • Protein that speeds up rxns w/o being changed (lowers activation energy) • http://my.hrw.com/sh/hm2/0030724872/student/ch02/sec02/qc06/hm202_02_q06fs.htm

23. Polarity • Polarity – • When a molecule has an uneven distribution of charge • Water - • Oxygen doesn’t share the e- equally with hydrogen • The oxygen pulls the e- closer, thus the oxygen has a partial negative charge and the hydrogen gets a partial positive charge (draw the picture)

24. Bonds • Hydrogen Bonds – muyimportante • Weak attraction between the partially negative oxygen and partially positive hydrogen • This is gives water some VERY IMPORTANT qualities

25. Hydrogen bonds creates surface tension – water “sticks” to itself • Which is more dense, water or metal? • Metal • Floating paper clip?!?! • Metal, but paperclip floats b/c water is weakly bonded and those bonds are not breaking.

26. States of Water • What is the most dense state of water? • Water • This is very important…b/c if ice was more dense lakes wouldfreeze solid and no life could survive

27. 9-30 Warm Up • What is activation energy? • Test and review sheets due Monday…review for the test tomorrow

28. Solubility • How well something will dissolve in a liquid • Water = polar….which allows it to dissolve other polar / ionic substances • Or substances that ionically bonded • NaCL • http://www.youtube.com/watch?v=gN9euz9jzwc&feature=related

29. Water and Oil • Do water and oil mix? Why / why not? • Below is the chemical structure of olive oil…it is NON-POLAR • The POLAR water does not dissolve / interact with the NON-POLAR oil.

30. In your notes…using a book • Define: • Cohesion – • attractive force of similar substances • Water to water • Adhesion – • Attractive force of different substances • Water to glass • Explain how capillary action or capillarity works

31. pH – • Measure of how acid / basic a substance is

32. Acids and Bases • Acids http://my.hrw.com/sh/hm2/0030724872/student/ch02/sec03/qc05/hm202_03_q05fs.htm • Have low pH • Have a lot of H3O+ (HCL or H2SO4) • H20 + HCl = H30+ + Cl- • http://my.hrw.com/sh/hm2/0030724872/student/ch02/sec03/qc06/hm202_03_q06fs.htm • Bases • High pH • Have a lot of OH- (NaOH) • H20 + NaOH = Na+ + OH- • http://my.hrw.com/sh/hm2/0030724872/student/ch02/sec03/qc07/hm202_03_q07fs.htm

34. Finished!