1.4. A 2.3 L cylinder containing nitrogen gas at a pressure of 2.8 atm is connected to a 5.5 L
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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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2.a) Carbon tetrachloride is an organic compound with the chemical formula CCl4. It is a
colorless liquid with a “sweet” smell.
i.
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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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4.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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7.1) Which of the following statements about scientific methods / theories is correct?
(1/0/0)
a) A scientific theory must be able to
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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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9.dehydrated cobalt (ii) chloride
Be sure to include subheadings (see bold text below) formulas, and units.
Chemical Equation: Write a generic
...
units.
Chemical Equation: Write a generic chemical equation for the dehydration of cobalt (II) chloride ∙ x hydrate (include the state symbols of the reactant and two products). [T2]
Mass of Reactants and Products:
a) Calculate the initial mass of the hydrated cobalt (II) chloride. [T1]
b) Calculate the final mass of the anhydrous cobalt (II) chloride remaining in the cruiio8icible. [T1]
c) Calculate the mass of water given off by the sample of hydrated cobalt (II) chloride. [T1]
Moles of Products:
a) Calculate the moles of anhydrous cobalt (II) chloride remaining in the crucible. [T1]
b) Calculate the moles of water released from the hydrate. {T1]
4. Mole Ratio
a) Create an experimental mole ratio between the b) and a). [T1]
5. Formula of Hydrate: State the chemical formula you have determined for this hydrate.
Round the formula to the closest whole number value for x. [T1]
Discussion/Conclusion Questions: [T6]
Based on the chemical formula of the hydrate, calculate the percentage composition (percent by mass) of the hydrated cobalt (II) chloride. Remember to determine the percentage of each element (Co, Cl, H, and O). [T2]
A possible source of systematic error in this experiment is insufficient heating. Suppose that the hydrate was not completely converted to the anhydrous form. Describe how this would affect: the calculated percent by mass of water and the experimental molecular formula (i.e. would x be higher, lower or the same).
Suppose a student spilled some of the hydrated cobalt (II) chloride. Describe how this would affect the calculated percent by mass of water (would it be higher, lower or the same) and the experimental chemical formula of the hydrate. [T2]
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10.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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18.An automated asteroid mining ship is traveling between two asteroids that are 1.5 x 106
km apart. The
mining ship has a
...
he
mining ship has a mass of 10,000 kg. The first rocket stage provides a thrust of 80 kN and is used over a
distance of 100,000 km. The second rocket stage provides a thrust of 40 kN and is used over a distance
of 200,000 km. The third rocket stage provides a thrust of 30 kN and is used over a distance of 400,000
km.
1) Calculate the final velocity of the rocket using two methods:
a. Using the work-energy theorem.
b. Using kinematics and Newton’s laws of motion. Hint: You might need to use the
quadratic formula to solve for t:
2) Calculate the total amount of time it takes for the mining ship to reach the other asteroid.
3) If the ship has a reverse thruster that provides 200 kN of thrust, how many km before reaching
the destination should the mining ship engage the reverse thrusters?
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20.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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