1)A researcher believes that there is a correlation between the number of cigarettes smoked per day and intelligence.  The following data were collected on 15 smokers.  Find Pearson's r.

Number of cigarettes (X) IQ score (Y)

7    10

49 6

41    15

38   5

37 12

19    4

35 19

40   11

1 3

10 3

18 22

21 17

15 12

7    9

38    13

n=15

Sum of X= 376          Sum of Y=161  

Sum of XY= 4,317

2) Interpret the findings from Question 2 in 1-2 sentences.

3)Give two examples, each time of two variables for which the Pearson's r might be expected to be between -.7 and -1.0.

A U-tube manometer employs a special oil having a specific gravity of 0.2 for the manometer fluid. One side of the manometer is open to local atmospheric pressure of 24.3 inHg and the difference in column heights is measured as 10 cm±1.0 mm when exposed to an air source at 35◦C. Standard acceleration of gravity is present. Calculate the pressure of the air source in pascals and its uncertainty.

1. (a)Plot the Voltage vs. Displacement graph of LVDT Transducer by moving the core in steps of 0.1mm in both Left and Right directions. (b)Calculate the Sensitivity of LVDT Transducer from the above graph. (c) What is the relationship between input voltage and output voltage of Transformer, given N1, N2 are number of turns in the primary and secondary coils respectively?

For the reaction Br₂ (g) + Cl₂ (g) → 2 BrCl Kp = 1.11 x 10^-4 at 150K.
a) If 1.0 atm each of bromine and chlorine gas are placed in an otherwise empty 1 L container and allowed to equilibrate at a temperature of 150K, what will be the partial pressures at equilibrium of all three gases?
Br₂  atm
Cl₂  atm
BrCl  atm
b) suppose 0.2 atm each of all three gases are placed in a selaed container and allowed to equilibrate at 150K. What will be the partial pressure of BrCl at equiibrium?
atm

For the reaction N₂O₄ (g) → 2 NO₂ Kc = 0.513 at a temperature of 500K.
a) If the concentration of NO₂ is 0.1 M at equilibrium, what is the equilibrium concentration of N₂O₄ ?  M
b) If the equilibrium concentration of N₂O₄ is 0.0085 M, what is equilibrium concentration of NO₂?  M

13. A reaction has K = 10 at 25 °C and has a standard enthalpy of reaction, ΔHorxn =-100 kJ/mol. What is

the equilibrium constant at 100 °C? Does this make sense in terms of Le Châtlier’s Principle?

14. Consider the following reaction:

COCl2 (g) ⇌ CO (g) + Cl2 (g) K = 8.3 x 10-4 at 360 °C; ΔHorxn = 109.5 kJ/mol

a) Initially, 2.0 moles of CoCl2 were placed in an empty 1.0 L container at 360 °C. When the

system reached equilibrium, what was the equilibrium concentration of Cl2?

b) After the system reached equilibrium, 0.5 mol of CO were added into the container and the

temperature was increased to 500 °C. When the system re-established equilibrium, what

was the concentration of Cl2?

1. Suggest a viable technique for purification of the crude SNAR product and outline the procedure for this technique and rationalize our choice. (SnAr mechanism)

22.3 Procedure

A solution of 4-chlorobenzyl amine (2.0 mmol, 1 mL 2.0 M soln. in 2-propanol, 2 equiv.) is added to a stirred solution of methyl 4-fluoro-3-nitrobenzoate (1.0 mmol) in 2-propanol (~10 mL) in a 25 mL round bottom flask equipped with a reflux condenser. The reaction mixture is heated to reflux for 30 min, cooled in an ice-water bath, and the product isolated by vacuum filtration. The crude product is rinsed with ice-cold 2-propanol (2 × ~3 mL), air-dried, and characterized via NMR (CDCl3) and IR spectroscopic analysis

In the simulation, select the Table Salt tab, and set the volume and the total number of sodium (Na+) ions as mentioned below. Allow the solution to attain equilibrium. Observe the number of dissolved ions and bound ions from the table displayed on the right. Then, identify which of the following solutions are saturated solutions.

1.0×10−23 L of solution containing 23 Na+ ions.
2.0×10−23 L of solution containing 81 Na+ ions.
3.0×10−23 L of solution containing 115 Na+ ions.
4.0×10−23 L of solution containing 121 Na+ ions.
5.0×10−23 L of solution containing 202 Na+ ions.
6.0×10−23 L of solution containing 213 Na+ ions.

Decide which of the following statements are true and which are false.

True False  Real gas molecules behave most ideally at low temperature and high pressure.

True False  At constant temperature, the lighter the gas molecules, the smaller the average kinetic energy.

True False  At constant temperature, the lighter the gas molecules, the smaller the average velocity.

True False  In order for two separate 1.0 L samples of O₂(g) and H₂(g) to have the same average velocity, the O₂(g) sample must be at a lower temperature than the H₂(g) sample.

True False  Ideal gas molecules have small volumes and exert weak attractive forces on one another.

True False  As temperature increases, the average kinetic energy of a sample of gas molecules increases.

1. Assume that the solubility of caffeine in water is 4.0 g/100 mL and in methylene chloride it is 16.0 g/100 mL at 25°C. What is KD for this system? 3. Once you calculate KD, calculate how much caffeine would be extracted by mixing 1.0 g of caffeine in 100 mL of water and performing three consecutive extractions with 25 mL CH2Cl2 each time. Show your work.

2. Assume you changed the solvent to ethyl acetate which has a KD for caffeine of 10. How much caffeine would you extract after three extractions 25 mL each? Show your work.

3. Is caffeine an acidic or basic compound? Answer using a balanced equilibrium equation for caffeine in water that includes the correct structure for caffeine.

Polar Covalent, Covalen or Ionic? What are each of their electronegative charges?

Q: My A:

1. ) K-O Ionic? 4.0(K)-2.0(O)= 2

2.) H-C Covalent 1.0(H)-1(C)=0

3.) S-C Covalent 3(S)-1(C)=2

4.) O-C Covalent 2(O)-1(C)=1

This is how I did it but its not correct as I am seeing in my textbook the numbers have decimals, for example:

NaCl 3.0 (Cl)-0.9(Na)=2.1 Ionic

Where does the 3.0 and 0.9 # come from? I though it was taking the period it was in and that representing the number as you can see in the breakdown above that is probably wrong.

Thank you!

Hydrogen peroxide, H2O2, decomposes to water and oxygen gas. What is the oxidation state (oxidation number) for oxygen in hydrogen perioxide?

If 23.6 mL of 0.200 M NaOH is required to neutralize 10.00 mL of a H3PO4 solution , what is the concentration of the phosphoric acid solution?

Start by balancing the equation for the reaction:  

H3PO4(aq) + NaOH(aq)  → Na3PO4(aq) + H2O(l)