7.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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17.Q2.BMPractice.5th
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1. Which best describes the difference between single cell and multicellular organisms? *
1 point
a. Single-cell organisms can perform all processes in one cell, but multicellular organisms need many cells to do specialized functions together.
b. Single-cell organisms need one cell to function, but multicellular organisms need lots of cells who all have the same job.
c. Single-cell organisms need many cells to do specialized functions together, but multicellular organisms can perform all processes in one cell.
d. Single-cell organisms need multiple cells with similar structures, but multicellular organisms need only one cell.
2. How does your brain move your arm? *
1 point
a. The brain sends a message to your bones to move your arm
b. The brain sends a message to your nerves to move your arm
c. The lungs send a message to your muscles
d. The muscles send a message to your brain
3. Which correctly explains the difference between the respiratory and circulatory system? *
1 point
a. The respiratory system includes your lungs and the circulatory system includes your heart
b. The respiratory system takes in oxygen and the circulatory system breaks down food
c. The respiratory system takes in water and carbon dioxide, but the circulatory system does not
d. The respiratory system includes the brain and the circulatory system includes to lungs
4. Which of the following is a learned behavior? *
1 point
a. Dimples when you smile
b. Ability to sing
c. Freckles
d. Hair color
5. These are all examples of: *
1 point
Captionless Image
a. Evaporation
b. Radiation
c. Transpiration
d. Percipitation
6. Which of these does NOT make a new material? *
1 point
a. Burning a wooden log
b. Iron nail rusitng
c. Ice melting
d. Mysterious color change
Explain why: *
This is a required question
7. What would you want to put your drink it to keep it cold? *
1 point
Metal (good conductor)
Plastic (bad conductor)
Explain why: *
8. How does the sun play a role in the water cycle? *
1 point
a. Heats water and turns it into water vapor gas
b. Cools gas to make water droplets and clouds
c. Creates strong winds
d. Causing it to rain
9. What will happen when a metal chair is left outside in the hot sun? *
1 point
a. Increase in weight
b. Decrease in weight
c. Increase in size
d. Decrease in size
10. What would the weight of the lemonade be if the water is 3.0 grams, the ice is 2.5 grams, and the mixture is 0.25 grams? *
1 point
a. 5.75 g
b. 5 g
c. 6.25 g
d. 10.1 g
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20.Given the scheme R= (ABCDEF), and following set of functional dependencies:
F = (AB®C, C®A, BC®D, ACD®B, D®EF, BE®C, CF®BD, CE
...
, ACD®B, D®EF, BE®C, CF®BD, CE ®AF).
(a) Find (BD)+
(b) Find (AB)+
(c) Find Candidate Keys for R
Question 3
Given the scheme R= (ABC), and following set of functional dependencies:
F = (A®BC, B® AC, C ® AB).
(a) Find closure (BC, F)
(b) Find at least one candidate key for R.
(c) Find at least one super-key for R which is not the same as your answer in
(b).
(d) Find at least one minimal cover for a relational scheme (ABC). Show work.
(e) Provide a 3NF decomposition for R.
Question 4
Consider the following set of FDs:
F = (A ® B, AB ® C, D ® AC, D ® E)
G = (A ® BC, D ® AE)
H = (A ® BC, B ® C, A ® B, AB ® C, AC ® D).
(a) Is F ≡ G? Show your work.
(b) Find the minimal cover for H. Show work.
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21.I have 5 questions I am stuck on. Please help!
1. Enter the correct answer in the box.
Facundo crochets and sells
...
chets and sells baby blankets, b. Each blanket requires 3 skeins of yarn, and the total number of skeins Facundo uses, y, varies directly as the number of blankets he crochets, b.
Write an equation that models this relationship.
2. The weight of an object, w, varies inversely as the square of its distance from the center of Earth, d. When an astronaut stands in a training center on the surface of Earth (3,960 miles from the center), she weighs 155 pounds. To the nearest tenth of a pound, what will be the approximate weight of the astronaut when she is standing on a space station, in orbit 240 miles above the training center?
3. The square of g varies inversely as h. When g = 16, h = 2. What is the value of h when g = 40?
4. The number of days, d, it will take Manny to read a book varies inversely as the number of pages, p, he reads per day. If k is the constant of variation, which equation represents this situation?
5. The battery life for Bruhier’s cell phone is longer when he has fewer apps running. When only one app is running, the battery will last for 16 hours. When four apps are running, the battery will only last for 4 hours.
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25.Hello there! I'm struggling with group solubility/solvability, Sylow subgroups, and nilpotency (university maths). I would like some assistance as soon
...
ersity maths). I would like some assistance as soon as possible (in the next few hours), so if you are unavailable, I would love it if another tutor could help. These are the questions that are similar to, but are not exactly the ones I am struggling with. Solving these would give me a better chance of solving my assignment. I don't know where to begin with these: Provide a non-solvable finite group G with solvable subgroups L, K, M such that G = LK = LM, M \neq K , and show that it fits the criteria. ///// Define G, a finite p -group, such that G isn't abelian. Let K \le G such that |G:K| = p , where K is abelian. Prove that there are either 1 or p + 1 such abelian subgroups, and if there are p + 1 , then the index of Z(G) in G is p^2 ///// Define N normal subgroup, G finite group, O the intersection of all maximal subgroups of G . Prove that G = ON and N \cap O is nilpotent. ///// Define p a prime number, G a finite group, K a Sylow p -subgroup of G . Assume M \le K and g^{-1}Mg \le K , where g \in G . Prove that g = km for some k \in N_G(K) (normaliser of K in G ) and some m \in C_G(M) (centraliser of K in G)
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31.Use g = 9.8 m/s2.
The diagram below is a top-down view of two children pulling a 11.8-kg sled along the
...
ng the snow. The first child exerts a force of F1 = 11 N at an angle θ1 = 45° counterclockwise from the positive x direction. The second child exerts a force of F2 = 6 N at an angle θ2 = 30° clockwise from the positive x direction.
Find the magnitude (in N) and direction of the friction force acting on the sled if it moves with constant velocity.
magnitude
direction (counterclockwise from the +x-axis)
What is the coefficient of kinetic friction between the sled and the ground?
What is the magnitude of the acceleration (in m/s2) of the sled if F1 is doubled and F2 is halved in magnitude?
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32.answer the questions an help me pleaseeee
Question 7: summarise the results of your phagocytosis assay, comparing the differences, if any,
...
say, comparing the differences, if any, between what you observe for cells with beads A and cells with beads B.
beads A x10 objective:
beads A x25 objective
beads B x10 objective
beads B x25 objective
Question 8 [short Text answer]
Marked out of 15.0
Using either your own cells with beads A or B, or the online images of the same, calculate a phagocytosis index for each treatment. Give the numbers of cells counted, numbers of beads etc and the final PI numbers as mentioned in the practical handout.
Question 9 [Text answer: Up to 250 words]
Marked out of 15.0
Beads A are clean beads , whereas beads B were pre-coated in surface layer of mouse immunoglobulin G (IgG). What differences might you expect (whether your experiment worked or not) upon exposing the mouse RAW 264.7 macrophages cells to these different beads. (do not give a mechanistic reason for it here, just what you might expect to happen)
Question 10 [Text answer: up to 250 words]
Marked out of 15.0
What immunological mechanism(s) might be involved in altering phagocytosis given your knowledge of the beads and cells, irrespective of whether you saw in your own experiment?
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33.Mary wants to throw a can straight up into the air and then hit it with a second can. She
...
collision to occur at height h = 5.0 m above the throw point. In addition, she knows that she needs t1 = 4.0 s between successive throws. Assume that she throws both cans with the same speed. Take g to be 9.81 m/s2.
(a) How long it takes (in seconds) after the first can has been thrown into the air for the two cans to collide? Answer to 4 significant figures. (b) Find the initial speed of the cans (in meters/second) to 4 significant figures.
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34.1) 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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38.I was wondering if you could help me step up my chem problems, i'm not sure how to begin
...
estion 1: Draven collected a 1ml sample from a local river. Draven added 99 ml of water to the sample. Draven then took 5 ml of the diluted sample, and determined the 5 ml sample to contained 10 mg of sodium chloride. what is the concentration of sodium chloride in the river?
question 2: how many grams of H2 could be produced when 13 g of H202 decompose?
question 3: how many molecules of carbon dioxide could be produced when 25 ml of a 0.8 M ethanol, c2h60, combusts with 5.18X10^23 molecules of oxygen? the unbalanced equation for the combustion of ethanol is given below:
2ch6O+302-> c02+h20
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40.For which value(s) of a does the curve y = x^2 + ax + 2
...
1 ? (Without using differentiation rules)
For each statement, explain why it must be true, or use an example to show that it can be false.
a)If y = f ( x ) has a horizontal tangent line at x = 1 then y = g ( x ) , where g ( x ) = f ( x − 1 ) + 1 , has a horizontal tangent line at x = 2 .
b)A tangent line always has exactly one point in common with the graph of the function.
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41.I dont understad these questions:
For which value(s) of a does the curve y = x^2 +
...
ave a horizontal tangent line at x = 1 ? (Without using differentiation rules)
For each statement, explain why it must be true, or use an example to show that it can be false.
a)If y = f ( x ) has a horizontal tangent line at x = 1 then y = g ( x ) , where g ( x ) = f ( x − 1 ) + 1 , has a horizontal tangent line at x = 2 .
b)A tangent line always has exactly one point in common with the graph of the function.
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42.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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