a 1000 watt iron produces 1000 joules (1 kilojoule) of energy per second. how many kilocalories of...

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A 1000 watt iron produces 1000 joules (1 kilojoule) of energy per second. How many kilocalories of energy is generated in one hour? (1 calorie=4.184 joules) 1000 joules|1 cal | kilo |60 sec|60 min= 860 kcal sec |4.184 J| 1000 |1 min |1 hr How many atoms of chlorine is in dinitrogen tetrachloride? What volume of oil will have the same mass at 51 mL of mercury? (oil density= 0.90 g/mL, mercury density=13.6 g/mL) 51 mL |13.6 g =693.6 g 693.6 g |1 mL = 771mL | mL |0.90g Study guide for Part 1 of Final Exam

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Page 1: A 1000 watt iron produces 1000 joules (1 kilojoule) of energy per second. How many kilocalories of energy is generated in one hour? (1 calorie=4.184 joules)

• A 1000 watt iron produces 1000 joules (1 kilojoule) of energy per second. How many kilocalories of energy is generated in one hour? (1 calorie=4.184 joules)– 1000 joules|1 cal | kilo |60 sec|60 min= 860 kcal

sec |4.184 J| 1000 |1 min |1 hr

• How many atoms of chlorine is in dinitrogen tetrachloride?

• What volume of oil will have the same mass at 51 mL of mercury? (oil density= 0.90 g/mL, mercury density=13.6 g/mL)– 51 mL |13.6 g =693.6 g 693.6 g |1 mL = 771mL | mL |0.90g

Study guide for Part 1 of Final Exam

Page 2: A 1000 watt iron produces 1000 joules (1 kilojoule) of energy per second. How many kilocalories of energy is generated in one hour? (1 calorie=4.184 joules)

• Know acid names and formulas: Hydrochloric acid, Nitric acid, Nitrous acid, Sulfuric acid, sulfurous acid, Phosphoric acid

• Physical change versus chemical change– Physical change is a change from solid to liquid or a

liquid to gas.– A chemical change is coming apart or combining with

other elements or compounds. Burning, rusting, decomposing, reacting with other compounds are examples.

Page 3: A 1000 watt iron produces 1000 joules (1 kilojoule) of energy per second. How many kilocalories of energy is generated in one hour? (1 calorie=4.184 joules)

• Precision versus accuracy– If your measurements are close to each other, you

have precision. If they match a known or expected value, then you have accuracy.

• Know pure element, compound, and mixture.– An element is made of just one kind of atom. O2 is

and element even though there are two of them together.

– A compound is two or more elements combined. Visually you would see two different atoms (spheres) joined.

– A mixture are two or more compounds mixed but not bonded together. Visually, you would see more than one kind of atom or molecule separate from each other.

O O

CO

CON N

Page 4: A 1000 watt iron produces 1000 joules (1 kilojoule) of energy per second. How many kilocalories of energy is generated in one hour? (1 calorie=4.184 joules)

• Know charge on polyatomic ions like chlorates, sulfates, carbonates, phosphates

• Know a precipitation reaction– NaCl(aq) + AgNO3(aq) AgCl(s) + NaNO3(aq)

Page 5: A 1000 watt iron produces 1000 joules (1 kilojoule) of energy per second. How many kilocalories of energy is generated in one hour? (1 calorie=4.184 joules)

• What is produced when alkali metals or alkaline earth metals are placed in water.

• Na + H2O or write

• 2Na(s) + 2HOH(l) 2NaOH(aq) + H2(g)

• What is difference between total ionic equation and net ionic equation? – Top is total ionic, bottom is net ionic– Na+

(aq) + Cl-(aq) + Ag+(aq) + NO3

-(aq) AgCl(s) + Na+

(aq)+ NO3-(aq)

– Cl-(aq) + Ag+(aq) AgCl(s)

Page 6: A 1000 watt iron produces 1000 joules (1 kilojoule) of energy per second. How many kilocalories of energy is generated in one hour? (1 calorie=4.184 joules)

• Figuring oxidation number of metals combined with non-metals such as 6A, & 7A non-metals. CuS, TiF4, TiO2, MnO4

-.– Always start with the oxidation number of the non-

metal. Sulfur and oxygen are -2.– Copper is 2+, Ti is 4+ for both, and Mn is +7.

• What would neutralize acids? Hydroxides (OH-) or carbonates (CO3

2-).

• Solubility rules. – Sulfates are soluble except for barium and lead.

Chlorides, bromides, and fluorides are soluble except for silver, lead, and mercury.

Page 7: A 1000 watt iron produces 1000 joules (1 kilojoule) of energy per second. How many kilocalories of energy is generated in one hour? (1 calorie=4.184 joules)

Given moles of one compound in a reaction, give moles of the others.– 2KClO3 2KCl + 3O2

– 0.245 moles O2 |2 mol KClO3 = 0.163 moles KClO3

|3 mol O2

• Discern excess or insufficient quantities in a reaction.– 2Al + 3Cl2 2AlCl3 (57 g Al & 200g of Cl), which reactant has

an excess and how much?– 54 g Al |1 mol= 2.1 mol Al

|27 g– 200 g Cl|1 mol = 5.6 mol Cl or 2.8 mole Cl2

|35.6 g– 2.1 mol Al | 3 mol Cl2 = 3.15 mol Cl2

| 2 mole Al– 2.8 mol Cl2| 2 mol Al = 1.87 mol Al

| 3 mole Cl2

– 2.8 moles of Cl2 can is only enough to react with 1.87 mol Al. Since there are 2.1 moles of Al, there is 0.23 (2.1-1.87) moles of Al in excess. For grams that’s 0.23 mol x 27g/mole = 6.2 grams.

Page 8: A 1000 watt iron produces 1000 joules (1 kilojoule) of energy per second. How many kilocalories of energy is generated in one hour? (1 calorie=4.184 joules)

• Figure % yield– 12 grams of calcium chloride is reacted with an excess of

sodium carbonate to make 9.5 grams of calcium carbonate. What was the % yield?

– CaCl2(aq) + Na2CO3(aq) CaCO3(s) + NaCl(aq)– 12 g CaCl2| 1 mol = 0.11 mol CaCl2

| 111 g– 9.5 g CaCO3| 1 mol = 0.095 mol CaCO3

| 100 g– 0.11 mol CaCl2 should produce 0.11 mole of CaCO3

however, it only produced 0.095 moles. So the fraction of what it did produced over what it should have is 0.095/0.11 = 86% yield.

– Equipment to make up a specific molar solution.– Moles per Liter. To find moles we need a balance. To measure

liter accurately, we use a buret or a volumetric flask. But to make molar concentratons, a compound is placed in some water and the level brought up to one liter. So a volumetric flask is the best.

• Evidence of reactions (heat, precipitate, gas, color change)

Page 9: A 1000 watt iron produces 1000 joules (1 kilojoule) of energy per second. How many kilocalories of energy is generated in one hour? (1 calorie=4.184 joules)

• Percent mass of one element in a compound– KMnO4, --- What is percent mass of manganese?– K = 39 g/mol, KMnO4 = 158 g/mol. % = 39/158 = 0.25 or 25%

• Balance a combustion reaction.• C5H8O3 + O2 CO2 + H2O

– Balance carbons with CO2 first, and hydrogen with water. Do O2 last.

• Basic dilution problem. – Conc x Vol =Conc x Vol– Concentrated = Diluted

• How many mL of 2.5 molar solution of HCl is needed to make up 350 mL of 0.1M HCl?

– Concentrated = Diluted– 2.5 M x ?mL = 0.1M x 350 mL– Divide both sides by 2.5M to have mL= 0.1Mx350mL/2.5M– ?mL = 14 mL

Page 10: A 1000 watt iron produces 1000 joules (1 kilojoule) of energy per second. How many kilocalories of energy is generated in one hour? (1 calorie=4.184 joules)

• Moles of one element in a compound, knowing the compounds mass and formula.

– 24 grams Na2SO4, how many moles of sulfur is there?– 24 g Na2SO4| 1 mol = 0.169 mol Na2SO4

| 142 g– Since there’s one sulfur in sodium sulfate, then the

moles of sulfur is the same as the sodium sulfate.

• Knowing energetic light has shorter wavelength and higher frequency. Radio waves, infrared, visible light, ultraviolet, x-rays, gamma rays. Which has the shortest wavelength, which has highest frequency? Gammas rays are the shortest wavelength and the highest freqeuncy.

Page 11: A 1000 watt iron produces 1000 joules (1 kilojoule) of energy per second. How many kilocalories of energy is generated in one hour? (1 calorie=4.184 joules)

• Heat of formation: page 244, 242

• Bond energies: page 341 for table, page 349 for problem.

• Electron configuration page 301, 302