2. Atoms and Molecules An Atom is made up of protons, electrons, and neutrons. An Element is a unique number of protons. When 2 or more atoms combine together chemically, it is called a molecule.
5. What is a Chemical Reaction? It is the rearrangement of atoms to form new molecules. CH4 + 2O2 CO2 + 2H2O
6. What is a Chemical Reaction? It is the rearrangement of atoms to form new molecules. CH4 + 2O2 CO2 + 2H2O
7. What is a Chemical Reaction? It is the rearrangement of atoms to form new molecules. CH4 + 2O2 CO2 + 2H2O
8. What is a Chemical Reaction? Some chemical reactions are exothermic They release energy as heat, light, or other forms.
9. What is a Chemical Reaction? Some chemical reactions are endothermic They absorb energy from the environment to proceed.
10. Chemical Properties Chemical properties can only be observed when the substances in a sample of matter are ________________. _____ and _____ are examples of chemical properties
11. Chemical Properties Chemical properties can only be observed when the substances in a sample of matter are ________________. Changing into different substances _____ and _____ are examples of chemical properties
12. Chemical Properties Chemical properties can only be observed when the substances in a sample of matter are ________________. Changing into different substances _____ and _____ are examples of chemical properties Flammability Reactivity
13. Triggers to Chemical Reactions Most reactions do not occur spontaneously. Most require some trigger to get started. This could be a spark or even a touch. Let’s watch a fun video of a chemical reaction that is sensitive to the touch!
18. Some Fun Experiments Pure Metallic Sodium in Water! http://www.youtube.com/watch?v=gFnNXkcoDSs
19. Recognizing Chemical Change Chemical changes are taking place if you see a _____, ______, or ______. Change in color Production of a gas Formation of a precipitate **If you are watching by recording, send me the sentence above with the answers**
20. Mixtures Iron and Sulfur powder in a the mixture So, it is hypothesis time: How can we separate the iron from the sulfur? Enter some ideas in the chat box.
21. Mixtures Iron and sulphur – the mixture How can we separate the iron from the sulphur? Use a magnet! Iron is magnetic, sulfur is not...
23. When iron and sulphur react + sulphur (S) atoms iron (Fe) atoms
24. When iron and sulphur react + sulphur (S) atoms iron (Fe) atoms iron sulphide (FeS) molecules
25. Differences between compounds and mixtures MIXTURES COMPOUNDS Mixtures can be separated easily Compounds can not be separated
26. Differences between compounds and mixtures MIXTURES COMPOUNDS Mixtures can be separated easily Mixture have the properties of the substances present in it Compounds can not be separated Compounds do not have the properties of the elements
27. Differences between compounds and mixtures MIXTURES COMPOUNDS Mixtures can be separated easily Mixture have the properties of the substances present in it No chemical change takes place when a mixture is made Compounds can not be separated Compounds do not have the properties of the elements A compound is always formed due to a chemical reaction
28. Differences between compounds and mixtures MIXTURES COMPOUNDS Mixtures can be separated easily Mixture have the properties of the substances present in it No chemical change takes place when a mixture is made There is no heat taken in or given out when a mixture is made Compounds can not be separated Compounds do not have the properties of the elements A compound is always formed due to a chemical reaction Heat is either taken in or given out when a compound is made
29. Differences between compounds and mixtures MIXTURES COMPOUNDS Mixtures can be separated easily Mixture have the properties of the substances present in it No chemical change takes place when a mixture is made There is no heat taken in or given out when a mixture is made A mixture can contain elements in any proportion Compounds can not be separated Compounds do not have the properties of the elements A compound is always formed due to a chemical reaction Heat is either taken in or given out when a compound is made A compound always contains the elements in fixed proportions, e.g. FeS contains 7g of iron to 4g of sulphur