4.4. A 2.3 L cylinder containing nitrogen gas at a pressure of 2.8 atm is connected to a 5.5 L
...
r containing nitrogen at 17.3 atm. What is the final pressure when both the cylinders have achieved equilibrium (reached the same pressure)?
6. An analytical procedure requires a solution of chloride ions. How many grams of BaCl2 must be dissolved to make 360 ml of 0.2 M Cl– ?
(M BaCl2 = 208 g/mol)
7. Find the concentration of chloride ions when 344.4 mL of 2.4 M NaCl is mixed with 364 mL of 2.9 M KCl?
8. A sample of an unknown gas had a density of 1.45 g/L at 20.5 °C and 1.2 atm. Calculate the molar mass of the gas.
(R = 0.08206 L·atm·mol-1·K-1)
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5.a) Carbon tetrachloride is an organic compound with the chemical formula CCl4. It is a
colorless liquid with a “sweet” smell.
i.
...
quid with a “sweet” smell.
i. Using the ground state electron configuration and excited state electron
configuration explain the hybridization of the central Carbon (C) atom. (7 Marks)
ii. Identify the orbitals that overlap to form the C-Cl bond. Draw a diagram to show
the orbital overlap. (3 Marks)
iii. What is the bond angle of CCl4? (1 Mark)
b) Consider a Fluorine atom (F) and a Fluorine anion (F-). Which of these two species would
you expect to have a larger radius? Explain your answer. (5 Marks)
c) Explain why the first ionization energy of Aluminum (Al) is less than that of Magnesium
(Mg). (4 Marks)
d) Assume the atom Oxygen(O) can form both cationic(O+) and anionic(O-) species. Place
the following species in order of increasing first ionization energy, starting with the lowest.
O+, O, O-
(5 Marks)
4.
a) Sea water contains roughly 28.0 g of NaCl per liter. (NaCl molar mass = 58.44 gmol-1).
i. Calculate the number of moles of NaCl in a liter of sea water. (2 Marks)
ii. Calculate the molarity of NaCl in sea water. (4 Marks)
iii. Calculate the mass by volume percent (W/V) of NaCl in sea water. (4 Marks)
Lowest first
ionization energy
…………………
…..
Intermediate
ionization energy
…………………
…..
Highest first
ionization energy
…………………
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8.Q1) (15 points) In the diagram below, M1 = 50 Kg, M2 = 20 Kg, mass and radius of the
...
g and 30 cm each, respectively. Both M1 and M2 rest on frictionless surfaces and the system starts from rest.
(a) Draw the fbd for each of M1, M2 and the pulley.
(b) Write the equations of motion for each of M1, M2 and the pulley.
(c) Calculate the linear acceleration of the two masses, as well as the angular acceleration of the pulley.
(d) Calculate the angular velocity of the pulley after M1 and M2 have been displaced linearly by 2 m.
Q2) (10 points) A basketball is thrown with an initial speed v0 of 10.8 m/s at 400 above horizontal, and it enters the hoop from above. The ball is released at 2.00 m above the ground. The hoop is 3.05 m above the ground and 10.0 m away from the player.
(a) Find the time at which the ball passes through the hoop.
(b) Find the ball’s velocity (express in component form) just when it enters the hoop.
(c) Find the ball’s maximum height.
Q3) (5 Points) An object is thrown up from the top of a building of height of 400 m with an initial velocity of 20 m/s.
(a) Find the position and the velocity of the object 5 s later.
(b) With what velocity will it hit the ground?
(c) At the same time the first object is thrown up, a second object is thrown up from the ground at 100 m/s. Will the two objects collide? If yes, calculate when and where,
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11.A 200.0 MeV photon is absorbed by a particle of
...
x.(a.) What is the mass (rest energy) of the particle after the collision in MeV? (b.) Show numerically that the gain in rest energy is equal to the photon’s energyminus the particle’s kinetic energy after the collision.
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18.2)Two books are accelerating to the right on a frictional surface and the coefficient of kinetic friction between the floor
...
ction between the floor and book is µk. Using the information given in the figure:
(a) draw free body diagrams for both the books, and also for the combined system (of mass m1+m2),
(b) find acceleration of the books along horizontal direction, and
(c) find the magnitude and direction of the force exerted by the left book on the right book.
3.A car of mass 1500-kg enters a circular path at point P and leaves at point Q (see the figure) at constant speed of 5.0m/s, and the frictional force acting on its tires is 2500-N.
a) how long it takes to reach point Q from point P, and
b) what should be the minimum value of the coefficient of static friction between the tires and the road?
4)In an elevator which is accelerating downward at 2.5ms−2 , a 25-kg block hangs from a spring attached to the ceiling of the elevator. If spring gets stretched by 0.15m, find its spring constant.
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19.1) Which of the following statements about scientific methods / theories is correct?
(1/0/0)
a) A scientific theory must be able to
...
a) A scientific theory must be able to be proven.
b) A scientific theory has been derived from known facts and always applies.
c) A scientific method should give different results depending on who performs the method.
d) Knowledge of our surroundings usually emerges through an interplay between theory and experiment.
2) The sides of a straight block are measured to 3,202 cm; 0.0012 cm and 11.2 cm, respectively. Calculate the volume of the straightening block and enter it with the correct number of value digits.
(2/0/0)
Number of words: 0
3) A 9.2 dm long and evenly thick rod rests on a support. 0.55 dm from one end, a dynamometer is hung so that the rod will hang horizontally. Then the dynamometer shows 4.4 N. How much does the bar weigh?
(1/1/0)
Number of words: 0
4) A bar AB that is homogeneous and evenly thick has a length of 2.70 m and is rotatable about an axis at A. The bar weighs 25 kg and is kept in equilibrium by a force F which has its point of attack in B. is 45 degrees. How big is the force F?
(1/1/0)
Saved!
25 * 9.82 = 245.5 N
Number of words: 6
5) A trolley rolls at a constant speed to the right. On the cart is an upward cannon that suddenly shoots a bullet. The carriage continues to the right with the same speed as before. Where does the bullet end up when it falls? For a detailed reasoning.
(1/1/1)
Number of words: 0
6) A river is 200 m wide. The water in the river flows at a speed of 2.5 m / s. A motorboat steers across the river at its maximum speed, which in stagnant water is 5.0 m / s. The boat is constantly heading perpendicular to the banks of the river. Where does the motorboat land on the other shore?
(2/0/0)
Number of words: 0
7) A ball with a mass of 2.0 hg moves at a constant speed in a circular path. The radius of the track is 1.5 m and it takes the ball 3.0 seconds to move one turn. How big is the centripetal force?
(1/1/0)
Number of words: 0
8) A bullet moves at a constant speed. Can we then safely say that the resultant of the forces acting on the bullet is zero? Motivate and discuss your answer.
(0/1/1)
Number of words: 0
9) A conductor is located between the poles of a permanent magnet. The current in the conductor goes in the direction of the plane of the paper (away from the reader). How is the force acting on the leader directed?
(1/0/0)
a) To the right of the figure
b) To the left in the figure
c) Downwards in the figure
d) Upwards in the figure
10) Protons enter horizontally from the left between two large metal plates at a speed v = 0.80 Mm / s. The plates are connected to a voltage source with the pole voltage U. Between the plates there is a homogeneous magnetic field with a flux density of 38 mT directed perpendicular to the plane of the paper. The distance between the plates is 1.5 cm. They want the protons to continue with unchanged direction and speed between the plates. Which of the plates should be connected to the positive pole of the voltage source and how large should the voltage U be?
(0/2/0)
Number of words: 0
11) The magnetic flux Φ through a 700-speed coil decreases linearly with time according to the diagram below. Calculate the voltage across the coil at time t = 1.0 ms.
12) The current in a coil with an inductance of 35 mH has a growth rate of 6.2 A / s at a given moment. What is the instantaneous value of the ems induced in the coil?
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22.A block of mass m1 lies on the horizontal plane, and another block of mass m2 is on it. A
...
thrown through the system of pulleys shown in the figure. A load of mass M = m1 + m2 is suspended from the movable pulley. At what ratio between the masses m1 and m2 will the blocks not slide over each other if the coefficient of friction between the blocks is µ, and there is no friction between the lower block and the plane? The mass of the thread and pulleys, as well as the friction in the pulleys, should be neglected; the thread is considered unstretchable.
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24.A sphere of mass M = 20kg and radius R = 10cm has its mass distributed in a way where
...
mediately guess it’s moment of inertia. To investigate whether it behaves more like a solid sphere or hollow sphere, you roll it down a rough ramp inclined at an angle of 30° with respect to the horizontal. The sphere rolls without slipping and you measure the velocity of the center of mass to be 3 m/s as it leaves the bottom of the ramp. The ramp’s length is 2 m and you release the sphere from the top of the ramp, a height of 1 m.
a) What is the moment of inertia of the sphere?
b) What is the angular speed of the sphere as it reaches the bottom of the ramp?
c) What is the frictional force on the sphere?
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25.Let's Play Ice Hockey!
9601686.png
An ice hockey player uses hockey stick to apply force on a motionless puck as shown on
...
motionless puck as shown on the picture above. The net force that the stick applies on the puck is 150N and the contact lasts for 7.5 ms. The mass of the puck is 166 g.
A) (1 point) Calculate the acceleration of the puck under the influence of the net force.
B) (2 points) Calculate the puck's change in momentum due to the impulse applied by the hockey stick.
C) (1 point) What is the velocity of the puck once it leaves the stick?
Puck travels over rough ice and comes to a stop after 25 m. The force diagram below shows all forces acting on the puck during that travel.
Screen Shot 2020-11-02 at 2.04.05 PM.png
D) (1 point) Calculate the work done on the puck by gravitational force.
E) (1 point) Calculate the work done on the puck by normal force.
F) (2 points) Calculate work done by friction force on the puck.
CNX_UPhysics_09_03_HockeyPuck.jpg
Now stationary, the puck (red) collides with a blue puck of the mass .332 kg moving to the left with velocity of 2.5 m/s. If collision is perfectly elastic calculate:
H) (2 points) Total momentum of blue+red puck system before collision?
I) (1 point) What is the total momentum of blue+red puck system after collision? How do you know?
J) (2 points) What is the velocity of the blue puck after collision?
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27.Suppose you measure a block’s weight by hanging it from a spring scale. You find that it
weighs 34.0 N
...
34.0 N when it’s not in the water. When it’s submerged in water (the density of water is
1.00 x 103 kg/m3) the scale now reads 27.0 N. (a) What is the density of the block? (b) If you
suspended another object from the block that has a density of 3.20 x 103 kg/m3, with both objects
submerged, what would the object's mass need to be for the scale to once again read 34.0 N?
Note: Part (a) is worth 7 points, and part (b) is worth 8 points.
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33.An elevator WEIGHS 1.0 x 10⁴ N. {Part A} Draw a free body diagram for each part of this questions
...
to show which force is larger [5 marks] {Part B} Determine the MASS of the elevator [2 marks] {Part C} The elevator begins to accelerate UPWARDS from rest at 5.0 m/s². What is the force tension in the cable? [3 marks] {Part D} The same elevator is moving UPWARDS and starts to DECELERATE at 3.0 m/s². What is the force tension in the cable? [3 marks] {Part E} The elevator moves DOWN at CONSTANT velocity at 10 m/s. What is the force tension in the cable? [2 marks] {Part F} The elevator cable snaps (and everyone screams!). What are the forces working on the elevator now? Draw a diagram [2 marks]
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37.Request for a written lesson for the material below:
SOC 170 - Exam 2 Study Guide
Exam 2 may consist of
...
nsist of true/false and/or multiple choice questions. You may use ONE page (8.5x11 inches) of handwritten notes on both sides.
Study the following terms and concepts as they are discussed in your assigned readings and course material. You should be able to identify, describe, and/or discuss the themes and/or approaches to justice. Don't just look for definitions, aim for understanding. Happy studying!
Immigration
How has immigration changed since the early 1800’s?
What is Friendship Park and how has it changed over the years?
Know the common question responses and myths and facts about immigrants and immigration.
Review readings from RDSJ; p. 102-109; from the reading, Injustice for All, what factors are contributing to the rise of an immigration policing regime in the U.S.? How does this impact the lives of undocumented immigrants, like Fatima?
In the film, what is the experience like for undocumented (and documented) immigrants held at the detention center featured in the film?
Terrorism
What percent of terrorist acts are committed by U.S. citizens?
What are the beliefs of the Christian Identity movement?
Though most reject the ideology of The Christian Identity movement, it is still popular because...?
What are the emerging trends in terms of domestic terrorism?
What is the difference between the uniform crime report and national crime victimization survey?
Contemporary Slavery
Know the forms of slavery in modern America.
Causes of modern slavery, why it persists, and how is it different from the past.
Know the major types of slavery in the world today.
Environment
Relationship between the U.S., natural resources, and world population
Describe the world’s supply of freshwater and how it is used, also in the U.S.
What is the relationship between water, food, health, manufacturing, and war? How many gallons of water for one pair of jeans?
How might privatizing water supplies impact society?
How might water impact tensions between countries?
The New Jim Crow (Alexander); Ch. 4-6
What is colorblindness? What should replace colorblindness?
Describe mass incarceration. Essentially, how does it operate?
What does the movement to end mass incarceration need to cultivate?
Describe the impact of The Quality Housing and Work Responsibility Act.
How did drunk driving laws compare to drug laws?
How did the white unemployment rate compare to the black unemployment rate in the early to mid 1980's?
With Affirmative Action, describe the unemployment rate in black communities.
What explains the high rates of violent crime in black communities?
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42.Hi! I need help with part (c) of this question. I have already done part (a) & (b):
A recent poll
...
conducted by Gallup Inc. asked the following question:
In general, how much trust and confidence to you have in the mass media - such as newspapers, TV, and radio - when it comes to reporting the news fully, accurately, and fairly? A great deal, a fair amount, not very much, or non at all?
53% of respondents has a negative view of the media, meaning they responded with either not very much or non at all.
Two people are randomly chosen, each is asked the poll question above. What is the probability
Part (a) that both have a negative view of mass media? 0.53^2
Part (b) neither have a negative view of the mass media? 0.47^2
Part (c) at least one of the two has a negative view towards the media? .53 (<- wrong)
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44.1) A hypothetical element exists as two isotopes: I = 42.00 amu and II = 49.00 amu. If the percent
...
bundance of isotope I is (1.94x10^1)%, what would be the calculated atomic mass (in amu)?
2) A hypothetical element exists as two isotopes: I = 78.00 amu and II = 84.00 amu. If the atomic mass of this element is found to be 80.33 amu, which isotope must be more abundant?
3) If the hypothetical polyatomic ion ThOM2- is called "thomite", what would be the formula and name of the acid formed by this ion?
4) How many atoms of hydrogen are there in a sample of (4.00x10^2) grams of NH3(g)?
5) How many O (oxygen) atoms are there in (6.40x10^2) grams of H3PO4?
6) How many moles of fluorine atoms are there in (5.80x10^2) grams of SF4?
7) When 3.50 g of titanium (Ti) reacts with oxygen, the resulting oxide compound weighs 5.84 g. What is the empirical formula of this oxide?
8) How many moles of molecules are there in (6.70x10^2) grams of CH4?
9) A chemical is found to be 80.0% C and the rest is H. If the molar mass of this chemical is known to be 90.2 g/mol, what is the molecular formula?
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45.A uniform beam of length L
and mass m shown in Figure
P12.16 is inclined at an angle
u to the horizontal. Its
...
izontal. Its upper
end is connected to a wall by
a rope, and its lower end rests
on a rough, horizontal sur-
face. The coefficient of static
friction between the beam
and surface is ms. Assume
the angle u is such that the static friction force is at its
maximum value. (a) Draw a force diagram for the beam.
(b) Using the condition of rotational equilibrium,
find an expression for the tension T in the rope in
terms of m, g, and u. (c) Using the condition of trans-
lational equilibrium, find a second expression for T in
terms of ms, m, and g. (d) Using the results from parts
(a) through (c), obtain an expression for ms
L
u
Figure P12.16
Q/C
S
vertical component of this force. Now solve the same
problem from the force diagram from part (a) by com-
puting torques around the junction between the cable
and the beam at the right-hand end of the beam. Find
(e) the vertical component of the force exerted by the
pole on the beam, (f) the tension in the cable, and
(g) the horizontal component of the force exerted
by the pole on the beam. (h) Compare the solution
to parts (b) through (d) with the solution to parts
(e) through (g). Is either solution more accurate?
19. Sir Lost-a-Lot dons his armor and sets out from the
castle on his trusty steed (Fig. P12.19). Usually, the
drawbridge is lowered to a horizontal position so that
the end of the bridge rests on the stone ledge. Unfor-
tunately, Lost-a-Lot’s
squire didn’t lower the draw-
involv-
ing only the angle u. (e) What happens if the ladder
is lifted upward and its base is placed back on the
ground slightly to the left of its position in Figure
P12.16? Explain.
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47.Gun Sales fall by $100 million due to the 'Trump slump' CNBC 9/12/17
"American Outdoor Brands, one of the largest gun
...
e of the largest gun manufacturers in the United States, experienced a 48.5 percent decrease in firearms revenue this quarter compared with the same time last year, The Guardian reports. Sales fell $100 million as a result of what has been called the "Trump slump."
The political climate has influence over gun sales. The expectation of many Americans that Hillary Clinton, the vocal pro-gun-control candidate, was going to win the presidential election in November is considered largely responsible for last year's surge.
People buy firearms at the highest rates when they fear regulations will be enhanced. The mass shooting at an Orlando nightclub shooting in June of 2016 also spurred record sales. According to the FBI's National Instant Criminal Background Check System (NICS), over 27.5 million firearm background checks for gun transactions were processed in 2016. That was over 4 million more than the previous year, and double the number of transactions in 2008."
Based on this article which of the following is true about the supply and demand of guns from 2016 to 2017
A)There was a decrease in demand for guns, and a decrease in the quantity supplied of guns
B)There was a decrease in quantity demanded, and a decrease in quantity supplied of guns
C)There was a decrease in the supply and guns and a decrease in the quantity demanded for guns.
D)There was a decrease in supply and a decrease in demand for guns.
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48.Problem Set 1. Name ________________________
1. For hexachlorobenzene (HCB), log Kow = 5.3, What would be the predicted concentration of HCB
...
, What would be the predicted concentration of HCB due to bioconcentration in the fat of fish that swim in water containing 0.00006 ppm of the chemical?
2. The fat content of breast milk averages a little over 4.0 g per 100 ml. Calculate the mass of DDE that would have been ingested by a typical breast-fed infant in 1972 consuming 300 ml of breast milk per feeding, if the milk contained about 500 ppb of DDE in its fat content.
3. The PCB concentration in Lake Michigan is declining according to a first-order rate law having a rate constant of 0.078 year-1. If the PCB concentration in the lake averaged 0.057 ppt (parts per trillion) in 1994, what was the concentration in 2004? In what year will the concentration fall to 0.005 ppt.
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