chemical reactions remember indications of a chemical change energy change color change ...
TRANSCRIPT
![Page 1: Chemical reactions Remember indications of a chemical change energy change Color change Precipitate formed Gas given off](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649e565503460f94b4d882/html5/thumbnails/1.jpg)
Chemical reactions
Remember indications of a chemical change energy change Color change Precipitate formed Gas given off
![Page 2: Chemical reactions Remember indications of a chemical change energy change Color change Precipitate formed Gas given off](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649e565503460f94b4d882/html5/thumbnails/2.jpg)
What is energy?
Anything that is not matter and can cause a change in matter
Examples: Heat Sound light
![Page 3: Chemical reactions Remember indications of a chemical change energy change Color change Precipitate formed Gas given off](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649e565503460f94b4d882/html5/thumbnails/3.jpg)
Symbols to know
yields or reacts to form+ plus or and(s) solid(l) liquid(g) gas(aq) dissolved in watercatalyst is written on
yields signHeat is a triangle on yields sign
![Page 4: Chemical reactions Remember indications of a chemical change energy change Color change Precipitate formed Gas given off](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649e565503460f94b4d882/html5/thumbnails/4.jpg)
Remember
Ionic compounds are usually solids (s)(but they can be dissolved in water)
All acids are dissolved in water (aq) Metals are solid except Hg Br2 is a liquid
![Page 5: Chemical reactions Remember indications of a chemical change energy change Color change Precipitate formed Gas given off](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649e565503460f94b4d882/html5/thumbnails/5.jpg)
Magnesium metal and sodium chloride dissolved in water react to form magnesium chloride dissolved in water and sodium metal
![Page 6: Chemical reactions Remember indications of a chemical change energy change Color change Precipitate formed Gas given off](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649e565503460f94b4d882/html5/thumbnails/6.jpg)
Try these!
Solid magnesium reacts with oxygen in the air to form solid magnesium oxide.
Bubbles of hydrogen gas and aqueous zinc sulfate are produced when zinc metal is added to sulfuric acid
![Page 7: Chemical reactions Remember indications of a chemical change energy change Color change Precipitate formed Gas given off](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649e565503460f94b4d882/html5/thumbnails/7.jpg)
Diatomic molecules
H2 N2 O2 F2
Cl2 Br2
I2
![Page 8: Chemical reactions Remember indications of a chemical change energy change Color change Precipitate formed Gas given off](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649e565503460f94b4d882/html5/thumbnails/8.jpg)
matter cannot be created nor destroyed (its conserved).
number of atoms reacted equals number of atoms produced
take an atom inventory
Law of Conservation of
Matter
![Page 9: Chemical reactions Remember indications of a chemical change energy change Color change Precipitate formed Gas given off](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649e565503460f94b4d882/html5/thumbnails/9.jpg)
Rules for Balancing Equations
1.Write reactants on left, products on right
2 Write correct formulas3. Take an atom inventory4. Balance the number of atoms by
placing a coefficient in front of the formula(DON’T CHANGE SUBSCRIPTS)
5. Repeat until all atoms are balanced6. Put coefficients in lowest terms
![Page 10: Chemical reactions Remember indications of a chemical change energy change Color change Precipitate formed Gas given off](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649e565503460f94b4d882/html5/thumbnails/10.jpg)
Practice
Balance and write the words:
Br2(l) + NaI(aq) NaBr(aq) + I2(s)
Al(s) +CuSO4 (aq)Al2(SO4)3(aq) +Cu(s)
![Page 11: Chemical reactions Remember indications of a chemical change energy change Color change Precipitate formed Gas given off](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649e565503460f94b4d882/html5/thumbnails/11.jpg)
Practice
Mercury metal is produced by heating a mixture of mercury(II)sulfide and calcium oxide. Other products are calcium sulfide and calcium sulfate.
![Page 12: Chemical reactions Remember indications of a chemical change energy change Color change Precipitate formed Gas given off](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649e565503460f94b4d882/html5/thumbnails/12.jpg)
Types of Chemical reactions
Combination(synthesis)A + B AB
DecompositionAB A + B
Single replacementA + BX AX + B
Double Replacement AX + BYAY + BX Combustion
HxCy + O2 CO2 + H2O
![Page 13: Chemical reactions Remember indications of a chemical change energy change Color change Precipitate formed Gas given off](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649e565503460f94b4d882/html5/thumbnails/13.jpg)
Combination(synthesis)
Mg + O2 MgO
Sodium and chlorine react to form
Iron and oxygen react to form iron (III) product
![Page 14: Chemical reactions Remember indications of a chemical change energy change Color change Precipitate formed Gas given off](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649e565503460f94b4d882/html5/thumbnails/14.jpg)
Decomposition
H2O2 H2O + O2
Water decomposes with electricity Into its elements
Calcium carbonate decomposes to form calcium oxide and carbon dioxide
![Page 15: Chemical reactions Remember indications of a chemical change energy change Color change Precipitate formed Gas given off](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649e565503460f94b4d882/html5/thumbnails/15.jpg)
Hydrogen H+Tin Sn+2,Sn+4
![Page 16: Chemical reactions Remember indications of a chemical change energy change Color change Precipitate formed Gas given off](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649e565503460f94b4d882/html5/thumbnails/16.jpg)
Single replacement
Mg + HCl MgCl2 + H2
look up on activity series(p106)Mg must be higher than H for a
reaction
Mg + KCl No reactionMg is lower than K so “ no go”
![Page 17: Chemical reactions Remember indications of a chemical change energy change Color change Precipitate formed Gas given off](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649e565503460f94b4d882/html5/thumbnails/17.jpg)
Activity Series and History
What were some of the first metals used by man? Copper age @5 –4000 BC Why?
What age came next? Bronze age 3 – 2000 BC (Trojan war) What is bronze?
What age came next? Iron Age 1000 BC on
![Page 18: Chemical reactions Remember indications of a chemical change energy change Color change Precipitate formed Gas given off](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649e565503460f94b4d882/html5/thumbnails/18.jpg)
Why Bother Discussing This? Locate copper, tin and iron Copper is found in metallic form
It is an uncombined element Look below copper, gold, mercury and
silver “coinage” metals
Tin is easy to turn into its elemental form
Iron requires lots of energy!
LiKBaSrCaNaMgAlMnZnFeCdCoNiSnPbHCuAgHgAu
![Page 19: Chemical reactions Remember indications of a chemical change energy change Color change Precipitate formed Gas given off](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649e565503460f94b4d882/html5/thumbnails/19.jpg)
Ionic Compounds
When an ionic compound dissolves in water, what actually happens?
![Page 20: Chemical reactions Remember indications of a chemical change energy change Color change Precipitate formed Gas given off](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649e565503460f94b4d882/html5/thumbnails/20.jpg)
The battle between water and “columbic” attraction
•Particles of opposite charge are attracted to each other. •This attraction is called columbic attraction
![Page 21: Chemical reactions Remember indications of a chemical change energy change Color change Precipitate formed Gas given off](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649e565503460f94b4d882/html5/thumbnails/21.jpg)
Ionic Solution
So an ionic solution is really a bunch of charged particles floating around
Water “hydrates” or surrounds each particle
Water keeps the Plus and minus charges from attracting each other
If the plus and minus are more attracted to each other than to the water, then they combine and make a precipitate - it is not soluble
![Page 22: Chemical reactions Remember indications of a chemical change energy change Color change Precipitate formed Gas given off](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649e565503460f94b4d882/html5/thumbnails/22.jpg)
Double Replacement
Metal ions replace each other
All reactants are aqueous Check products on solubility
table to see if solid or aqueous
MgSO4 + NaCl BaSO4 + Ag2CO3
![Page 23: Chemical reactions Remember indications of a chemical change energy change Color change Precipitate formed Gas given off](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649e565503460f94b4d882/html5/thumbnails/23.jpg)
Combustion
Completehydrocarbon + O2 CO2 + H2O
C5H10 + O2 CO2 + H2O
IncompleteHydrocarbon + O2 CO + H2O
C + H2O
![Page 24: Chemical reactions Remember indications of a chemical change energy change Color change Precipitate formed Gas given off](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649e565503460f94b4d882/html5/thumbnails/24.jpg)
Practice
Balance and write the words:
Br2(l) + NaI(aq) NaBr(aq) + I2(s)
Al(s) +CuSO4 (aq)Al2(SO4)3(aq) +Cu(s)
![Page 25: Chemical reactions Remember indications of a chemical change energy change Color change Precipitate formed Gas given off](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649e565503460f94b4d882/html5/thumbnails/25.jpg)
Practice
Balance and write the words:
Br2(l) + NaI(aq) NaBr(aq) + I2(s)
Al(s) +CuSO4 (aq)Al2(SO4)3(aq) +Cu(s)
![Page 26: Chemical reactions Remember indications of a chemical change energy change Color change Precipitate formed Gas given off](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649e565503460f94b4d882/html5/thumbnails/26.jpg)
Practice
Balance and write the words:
Br2(l) + NaI(aq) NaBr(aq) + I2(s)
Al(s) +CuSO4 (aq)Al2(SO4)3(aq) +Cu(s)
![Page 27: Chemical reactions Remember indications of a chemical change energy change Color change Precipitate formed Gas given off](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649e565503460f94b4d882/html5/thumbnails/27.jpg)
C + O2 CO2
C-1 O-2 C- 1
O – 2