greysalmon406

In an SN1 reaction, why would the reaction rate increase with an increase in the solvent polarity? What would be the affect of halide concentration of the reaction rate of an SN11 reaction and why?

Explain why carbon always follows the octet rule.

A solution containing equal masses og glycerol(C3H8H3)and water has a density of 1.10g/ml.C=12g/mole,H=1g/mole,O=16.0g/mole.Caculate the molality og glycerol.

The solubility of is  per   of water at and  at . What mass (in grams) of will crystallize out of solution if exactly  of its saturated solution at  is cooled to ?

Find the first-order rate constant for the disappearance of A in the gas reaction A --> 1.6R if the volume of the reaction mixture, starting with pure A increases by 50% in 4 minutes. The total pressure within the system stays constant at 1.2 atm and the temperature is 25 degrees celcius.

How do Glucagon and insulin influence the metabolism of major energy nutrients? (Terms that should be included in this discussion: glucose, glycogen, phosphorylase, lipase, triglycerides, glycolysis, gluconeogenesis, glycogenesis, glycogenolysis, diabetes)

Calculate the average charge of Gly-His at pH 7.40 (pK_a = 3.5, 6.0, 9.3). (Hint: remember that the answer must be ± 0.5 of the dominant charge.)

Two experiments were done. One, using an mL of an unknown solution + nmL iron (III) solution + aspirin. The other, , mL iron (III), and acetylsalicylic acid. Explain why the solutions have a purple color after the iron reagent is added. Yes, the answer is because it is absorbing the other colors, but what is absorbing the other colors?

These tubes were put through the spectrophotometer after all substances had been added. Explain why the spectrophotometer is 'blanked' with JUST the iron reagent. Why couldn't deionized water be used?

Which observation(s) (all true) is/are directly related to hydrogen bonding?

I. Hydrogen has the lowest density of all gases.

II. The boiling point of is greater than the boiling point of .

III. The boiling point of (ethene) is less than the boiling point of (ethane).

IV. Ice floats on liquid water.

V. Hydrogen is less electronegative than carbon.

A. II only

B. III, IV, V only

C. IV only

D. II, III, IV only

E. II, IV only

Which of the following is a molecular characteristic that makes a ligand more likely to be bound by a nuclear receptor rather than a GPCR (select all that apply)?

If a solution with a couple of drops of bromocresol purple indicator is titrated with , then the color change would be:

A. yellow (acidic) to purple (basic)

B. purple (acidic) to yellow (basic)

C. purple (basic) to yellow (acidic)

D. yellow (basic) to purple (acidic)

E. purple (basic) to colorless (acidic)

A 4.20 mol4.20 mol sample of solid AA was placed in a sealed 1.00 L container and allowed to decompose into gaseous BB and C.C. The concentration of BB steadily increased until it reached 1.20 M,1.20 M, where it remained constant.

Then, the container volume was doubled and equilibrium was re‑established. How many moles of AA remain?

find the partial pressure of water at 25°C, 26°C, and 27°C

The reaction quotient Q and equilibrium constant K for a chemical reaction are the same quantities __________.

A. at room temperature and 1 atm of pressure

B. in the presence of a catalyst

C. at standard temperature and pressure

D. when ΔS = 0

E. when the rate of the forward reaction equals the rate of the reverse reaction

(a) If an electric car is capable of going 225 km on a single charge, how many charges will it need to travel from Seattle, Washington, to San Diego, California, a distance of 1257 mi, assuming that the trip begins with a full charge? (b) If a mi- grating loon flies at an average speed of , what is its average speed in ? (c) What is the engine piston displacement in liters of an engine whose displacement is listed as 450 in.3 ? (d) In March 1989 the Exxon Valdez ran aground and spilled 240,000 barrels of crude petroleum off the coast of Alaska. One barrel of petroleum is equal to 42 gal. How many liters of petroleum were spilled?

Suppose 10.0 moles of C3H8 (g) are compressed at 300 K with 4.860 dm3. a) ideal gas and b)
Find the pressure exerted by propane from van der Waals equations of state. This
Calculate the compression factor according to the calculations and interpret the results.
For propane, a = 8,779 dm6
atm mol-2, b = 0.08445 dm3 mol-1

Sally has constructed a concentration cell to measure Ksp for MCln. She constructs the cell by adding 2 mL of 0.05 M M(NO3)n to one compartment of the microwell plate. She then makes a solution of MCln by adding KCl to M(NO3)n. She adds 1.369 mL of the resulting mixture to a second compartment of the microwell plate. Sally knows n (the charge on the metal ion) = +2 She has already calculated [Mn+] in the prepared MCln solution using the Nernst equation. [Mn+] = 4.568 M How many moles of [Cl-] must be dissolved in that compartment? _____ mol (Hint: start by finding how many moles of [Mn+] are dissolved in that compartment of the microwell plate) Provide your response to three digits after the decimal.

Coal gasification can be represented by the equation: 2 C(s) + 2 H2O(g) ĺCH4(g) + CO2(g) ǻH = ? Use the following information to find ǻH for the reaction above. CO(g) + H2(g) ĺC(s) + H2O(g) ǻH = -131 kJ CO (g) + H2O(g) ĺCO2(g) + H2(g) ǻH = -41 kJ CO(g) + 3 H2(g) ĺCH4(g) + H2O(g) ǻH = -206 kJ Original Order: 4

Study the reactions for the formation of compounds from their elements. I. C(s) + O2(g) → CO2(g) ΔHf = −394 kJ II. H2(g) + 12 1 2 O2(g) → H2O(l) ΔHf = −242 kJ III. 2C(s) + 3H2(g) → C2H6(g) ΔH =−84 kJ The combustion of C2H6 is shown by the following equation: C2H6(g) + 72 7 2 O2(g) → 2CO2(g) + 3H2O(l) Which option correctly gives the enthalpy of combustion of 0.2 moles of C2H6(g)?

A.) In the Oxygen Lab, we performed a variety of reactions involving oxygen. Please provide the balanced, chemical equation for the reaction between copper and oxygen that produced copper (II) oxide.

B.) In the Oxygen Lab, we performed a variety of reactions involving oxygen. Please provide the two balanced, chemical equations for the two steps involved in the production of phosphoric acid starting from phosphorous and oxygen.

A student used of vegetable oil to heat of water from an initial temperature of to a final of . Which statement correctly describes the heat flow in calories? The specific heat of water is and specific heat of the oil is . (Ignore heat gained or lost by the surrounding)

a) the water lost 127 calories of heat and oil gained 127 calories of heat.

b) the water gained 127 calories of heat and oil lost 127 calories of heat.

c) the water lost 144 calories of heat and oil gained 144 calories of heat.

d) the water gained 144 calories of heat and oil lost 144 calories of heat.

Predict the standard potential for the galvanic cell below.

A student over titrates a sample of cream of tartar. How will that affect the result for the molar mass of the acid? What if the student under titrates?

What it the hydrogen ion concentration of a solution with a pH 10? How about a solution with a pH of 13? 

Distinguish between free energy change, and standard free energy change in biochemistry.

Which of the following substances is more soluble in a nitric acid solution then in a sodium hydroxide solution?

a.  

b.  

c.  

d.  

e.  

The typical concentration of glucose in the blood after a pancake breakfast is  . The concentration of glucose within cells is estimated to be about .

A) Calculate the concentration of glucose in the blood (1 pt).

B) Calculate the Gibbs free energy, ∆G, available for the transport of glucose into cells using these concentrations. Assume  . (3 pts)

C) Is the transport of glucose into the cell spontaneous? Why (or why not)? (1 pt)

D) Based on your answer to (C), would a pancreatic cell release insulin? (1 pt)

If an unknown solution contains starch and sucrose how could you prove this? 

Cyanide ion can be determined indirectly via atomic absorption based on its ability to dissolve silver while passing through a porous silver membrane, as described by the chemical equation 4 Ag(s) + 8 CN+2 H2O + O2 →4 Ag(CN)2 + 4 OH A series of silver standards analyzed by atomic absorption spectroscopy gave a linear calibration curve with a slope of 807 meter units per ppm Ag. (The "meter units" are linearly proportional to absorbance, and ppm Ag means µg Ag/mL solution.) An unknown Ag solution passed through the silver membrane gave a signal of 198 meter units. (a) Calculate the molarity of CN¯in the unknown. [Answer: 4.55 x 10“ M] (b) Briefly state a data analysis assumption you make to solve the problem. (That is, we can take for granted that all of the reagents are pure and that there is no experimental error that makes the calculations invalid.)

Q1: Calculate AH and AS for the following reaction: NHẠNO3(s) + H20(1) → NH4" (aq) + NO; (aq) Compound AH (kJ/mol) AS (J/mol-K) NHẠNO3(s) -200 100 NH4+ (aq) -180.51 199.4 NO3(aq) -405.0 255.4

3/?!

Calculate AH and AS for the following reaction: NH,NO3(s) + H20(1) → NH,* (aq) + NO3" (aq) Compound AH (kJ/mol) AS (J/mol-K) NHẠNO3(s) -200 100 NH4+ (aq) -180.51 199.4 NO3(aq) -405.0 255.4

delta G ?

A hydrogen peroxide solution is analyzed by adding a slight excess of standard KMNO, solution and back-titrating the unreacted KMNO, with standard Fe+ solution. A 0.587-g sample of the H,O, solution is taken, 25.0 mL of 0.0215 M KMNO, is added, and the back-titration requires 5.10 mL of 0.112 M Fe?+ solution. What is the percent H,O, in the sample? 

Determine the molar mass

Students needed to make a solution of 0.50 M nitrate, NO3
, using Ca(NO3)2. What
concentration of Ca(NO3)2 would they make? Show your calculation.

The purity of a sample of sodium oxalate, Na2C2O4, is determined by titrating 
with a standard solution of KMnO4. If 0.5116-g sample re-quires 35.62 mL of 
0.0400 M KMnO4 to reach the titration’s end point, what is the %w/w Na2C2O4 
in the sample

I need help on my final question, had so much trouble on the first question

In an experiment, potassium chlorate decomposed according to the following chemical equation.
KCIO3 -- KCI + O2
(Molar mass of KClO3 = 122.5 g/mol; KCl = 74.55 g/mol; O2 = 31.998 g/mol)
If the mass of potassium chlorate was 240 grams, which of the following calculations can be used to determine the mass of oxygen gas formed

The total mass of twenty tablets used in nutritional disorders is 44,262 g and is ground and powdered. 5,996 g powder sample taken from here is dissolved in HNO3 and the iron is completely converted to Fe (III). After heating, 0.528 g of Fe2O3 (MA = 159.69 g / mol) was obtained. Find the amount of FeSO4.7H2O (M.A. = 278.01 g / mol) in each tablet.