Principles of Chemistry I

Principles of Chemistry II

Survey of Chemistry II

Quiz_17_Key.pdf.docx-Name Jacob D. Schroeder Fall 2020

A 2 + 2 B → 2 AB B. 4 A 2 + 6 B → 6 AB + A 2 C. A 2 + B → AB D. 6 AB + A 2 → 4 A 2 + 6 B E. 2 AB → A 2 + 2 B F. AB → A 2 + B The first box has 6 purple spheres and 4 molecules of brown spheres. One purple combined with one brown to make 6 AB molecules, while one molecule of brown spheres remains unreacted. (  6 B + 4 A 2 → 6 AB + A 2 Since A 2 appears on both sides of the equation, the one in the products cancels o

CHEM | 1211 | Principles of Chemistry I | exam | A 2 + 2 B → 2 AB B. 4 A 2 + 6 

BOYLE’S LAW The volume of a given sample of gas at constant temperature varies inversely with the pressure. IMPORTANT DEFINITIONS Volume: amount of three-dimensional space occupied by a substance Temperature: measure of the random motions (average kinetic energy) of the components of a substance Pressure: force per unit area MODULE 3 UNIT 3 Experiment 1 GO TO THIS WEBSITE Animated Boyle’s Law Study the animation at this website. Note that the temperature is held constant at 300°C. Note the relationship between the volume (when the gas is compressed into a smaller volume and the pressure. Volume V and pressure P are shown in the graph to the right of the animation. Answer this question: At a constant temperature, when volume is decreased, what happens to pressure? (pressure rises) Read the information about Boyle’s Law, on this web page. http://www.grc.nasa.gov/WWW/K-12/airplane/aboyle.html Next, go to this website: What factors influence the pressure of a gas in a container? 1. Familiarize yourself with the animation. 2. There is a beaker containing a gas. It sits on a hotplate. A thermometer measures temperature in degrees Celsius. Click on the ‘Temperature’ button, above the thermometer. Now, you can adjust the temperature, by clicking on the buttons on the hotplate: LO = 60°C MED = 100°C HI = 140°C 3. A pressure gauge measures pressure in kPa (kilopascals). 4. There is a plunger in the beaker that can be adjusted to make different volumes. Click on the ‘Volume’ button, above the pressure gauge. Now, you PERFORM EXPERIMENT AND RECORD DATA Set volume at 200 ml. Record pressure ................ Set volume at 400 ml. Record pressure ................. Set volume at 600 ml. Record pressure ................. Set volume at 800 ml. Record pressure ................. Set volume at 1000 ml. Record pressure ................ Now, make a graph of volume (x-axis) and pressure (y-axis). Make your x-axis to show from 0 to 1000ml. Make your y-axis to show from 0 to 150 kPa. Your points will be (200, ..... ) (400, ...... ) (600, ...... ) (800, ...... ) and (1000, ....... ). [ ........ is the numbers you recorded for pressure] Next, set temperature at 100°C and record data for the five different volumes. Finally, set temperature at 140°C and record data for the five different volumes. Now, you have three sets of data and three graphs. The graphs must be submitted as part of the experiment. ANSWER SHEET FOR BOYLE’S LAW EXPERIMENT Fill in the answer sheet and then submit it via the Assignment drop-box. Question (first website) (1 point) 1. At a constant temperature, when volume is decreased, what happens to pressure? a) decreases b) i ncreases c) stays the same Data: (2 points each - 15 points) can left-click your mouse on the plunger, in the beaker, and drag the plunger up and down in the beaker. It will stop at: 200 ml, 400 ml, 600 ml, 800 ml, and 1000 ml. http://www.glencoe.com/sites/common_assets/science/virtual_labs/PS08/PS08.html

CHEM | 1152 | Survey of Chemistry II | homework | BOYLE’S LAW The volume of a gi

MODULE 2 UNIT 3 Assignment Part A 1. a. Explain how electronegativity changes when you move down a group (column) of the periodic table, from the top to the bottom. 2 marks Electronegativity changes when you move down a group of the periodic table by decreasing as you get further down the group from top to bottom. b. Explain how electronegativity changes when you move across a period (row) of the periodic table, from left to right. 2 marks Electronegativity changes when you move across a period from left to right of the periodic table by increasing as you move left to right. 2. Calculate the diﬀerence in electronegativity between the atoms participating in covalent bonds for each of the following compounds. Then, select the choice corresponding to the correct structural diagram, including the polarity of the bonds, for each compound. a) HBr 2.8-2.1=.7 The diﬀerence is .7 and this compound HBr is polar and linear because it has two atoms and one single bond i. This one is correct ii. iii. b) CH 4 2.5-2.1 = .4 The diﬀerence is .4 and this compound is non polar i. ii. This one is correct iii. Note: The molecule of CH 4 and a few others don’t follow the rule we’ve established to determine the order of atoms in the formula. According to our rule, hydrogen should appear ﬁrst in the formula CH 4 . c) NF 3 4.0-3.0=1.0 The diﬀerence is 1.0 i) ii) This one is correct iii)  d) Ol 2 3.5-2.5=1.0 The diﬀerence is 1.0 i) ii) iii) This third one is correct 8 marks Total 12 marks Submission Instructions Submit your assignment using the drop box on the Assignment page for this unit. https://olmoodle.ontariolearn.com/mod/resource/view.php?id=348952

CHEM | 1152 | Survey of Chemistry II | homework | MODULE 2 UNIT 3 Assignment Par

1 MODULE 5 UNIT 2 Assignment Part A 1. Ammonia is produced in great quantity by bringing about a reaction between nitrogen and hydrogen, as seen in the following equation: (6 marks) N 2 + 3H 2  2NH 3 Use this equation to calculate the number of moles of ammonia produced when: a) 10 moles of nitrogen react with excess gaseous hydrogen. Number of moles of NH 3 = 3 moles of H 2 x 10 moles of N 2 1 moles of N 2 = 20 moles b) 30 moles of hydrogen react with excess nitrogen. Number of moles of N 2 = 2 moles of NH 3 x 30 moles of H 2 3 moles of H 2 = 20 moles c) 20 moles of hydrogen react with 40 moles of nitrogen. Hint: One of the reactants will be in excess, that is, it will not be consumed completely. Number of moles of NH 3 = 1 moles of N 2 x 40 moles of N 2 1 mole of H 2 = 13.3 moles 2 2. When iron reacts with oxygen at high temperatures, a magnetic iron oxide is produced: 3Fe + 2O 2  Fe 3 O 4 a. How many moles of iron and oxygen are required to produce 10 moles of magnetic iron oxide? (4 marks) Number of moles of Fe = 2 moles of O2 x 10 moles of Fe3O4 1 mole of Fe3O4 = 20 moles of Fe Number of moles of O2 = 3 moles of Fe x 10 moles of Fe3O4 1 mole of Fe3O4 = 30 moles of O2 3 b. How many moles of oxygen are required to react with 30 moles of iron? (2 marks) Number of moles of O2 = 30 moles of Fe x 2 moles of O2 3 mole of Fe = 20 moles of O2 c. If a reaction is brought about between 60 moles of iron and 60 moles of oxygen, i) which reactant will be in excess and by how many moles? Number of moles of Fe = 60 moles of Fe x 1 moles of Fe3O4 3 mole of Fe = 20 moles of Fe3O4 Number of moles of O2 = 60 moles of O2 x 1 moles of Fe3O4 2 mole of O2 = 30 moles of O2 Check: 30 moles of Fe3O4 x 2 moles of O2 x 1 molesof Fe3O4 1 molesof Fe3O4 = 30 x 2 / 1 = 60 moles Therefore oxygen is in excess by 20 moles ii) calculate the number of moles of magnetic iron oxide produced. Hint : To find which reactant is in excess, calculate how many moles of one reactant are required to react with the other reactant. (4 marks) Number of moles of Fe2O4 = 20 moles of Fe3O4 x 3 moles of Fe 1 mole of Fe3O4 = 60 moles of Fe The number of moles of Fe3O4 is 60 moles Total 16 points Submission Instructions 4 Submit your assignment using the drop box on the Assignment page for this unit. https://olmoodle.ontariolearn.com/mod/resource/view.php?id=348999

All courses in CHEM

Popular Documents