Calculate the height of a column of carbon tetrachloride, CCl4(l), with a density of 1.59 g/mL that exerts the same pressure as a 15.2 cm column of Mercury, Hg(l), that has a density of 13.6 g/ml. Express your answer in meters. Please only enter the numerical value of your answer.
In: Chemistry
A sample of a concentrated fluorescent reagent was serially diluted with three steps using a variable volume 100 to 500 μL micropipetor and 10.00 mL Class A volumetric flasks. The concentrated reagent had a fluorescent signal of 653.4 and the diluted sample produced 0.057 fluorescence units. Unfortunately the steps followed for the dilution were lost. What were those steps?
In: Chemistry
In your own words, clearly explain the process of electrolysis of water. Include a description of the equipment involved, as well as the resulting chemical reaction(s).
In: Chemistry
Part A What is the pH of a buffer prepared by adding 0.809 mol of the weak acid HA to 0.608 mol of NaA in 2.00 L of solution? The dissociation constant Ka of HA is 5.66×10−7. Part B What is the pH after 0.150 mol of HCl is added to the buffer from Part A? Assume no volume change on the addition of the acid. (Express answer to 3 decimal places) Part C What is the pH after 0.195 mol of NaOH is added to the buffer from Part A? Assume no volume change on the addition of the base.
In: Chemistry
A voltaic cell is constructed that uses the following reaction
and operates at 298 K:
Zn(s)+Ni2+(aq)→Zn2+(aq)+Ni(s).
a. What is the emf of this cell when [Ni2+]= 2.10 M and [Zn2+]= 0.160 M ?
b. What is the emf of the cell when [Ni2+]= 0.100 M and [Zn2+]= 0.860 M ?
Thanks!
In: Chemistry
The atmosphere slowly oxidizes hydrocarbons in a number of steps
that eventually convert the hydrocarbon into carbon dioxide and
water. The overall reactions of a number of such steps for methane
gas is as follows:
CH4(g)+5O2(g)+5NO(g)→CO2(g)+H2O(g)+5NO2(g)+2OH(g)
Suppose that an atmospheric chemist combines 145 mL of methane at
STP, 895 mL of oxygen at STP, and 54.5 mL of NO at STP in a 2.0
−Lflask. The reaction is allowed to stand for several weeks at 275
K.
Part A
If the reaction reaches 90.0% of completion (90.0% of the limiting reactant is consumed), what are the partial pressures of each of the reactants in the flask at 275 K?
Enter your answers numerically separated by commas.
|
|
||||
| PCH4,PO2,PNO= | atm |
Part B
If the reaction reaches 90.0% of completion (90.0% of the limiting reactant is consumed), what are the partial pressures of each of the products in the flask at 275 K?
Enter your answers numerically separated by commas.
|
|
||||
| PCO2,PH2O,PNO2,POH= | atm |
Part C
What is the total pressure in the flask?
In: Chemistry
Calculate the freezing point and boiling point in each solution, assuming complete dissociation of the solute.
a)Calculate the freezing point of a solution containing 10.8
g FeCl3 in 172 g water.
b)Calculate the boiling point of a solution above.
c)Calculate the freezing point of a solution containing 4.3 % KCl
by mass (in water).
d)Calculate the boiling point of a solution above.
e)Calculate the freezing point of a solution containing 0.155 m MgF2.
f)Calculate the boiling point of a solution above.
In: Chemistry
Which of the following are true statements about equilibrium systems?
True/False For the following reaction at equilibrium:
2 H2(g) + O2(g) ⇌ 2 H2O(g)
the equilibrium will shift to the left if the volume is
doubled.
True/False For the following reaction at equilibrium:
H2(g) + F2(g) ⇌ 2HF(g)
removing H2 will decrease the amount of F2
present once equilibrium is reestablished.
True/False For the following reaction at equilibrium:
CaCO3(s) ⇌ CaO(s) + CO2(g)
adding more CaCO3 will shift the equilibrium to the
right.
True/False Increasing the temperature of an exothermic reaction
shifts the equilibrium position to the right.
True/False For the following reaction at equilibrium:
CaCO3(s)⇌ CaO(s) + CO2(g)
increasing the total pressure by adding Ar(g) will shift the
equilibrium to the right.
In: Chemistry
A piece of copper wire is 50ft long and has a dimater of 2.0 mm. Copper has a denisty of 8.92 g/cm3. What is the mass of copper? Express the answer in kg. (1ft = 30.48 cm, 1 cm = 10 mm and Volume is 3.14 x r2x1)
Please explain and help ! :(
In: Chemistry
One electrode compartment consists of an aluminum strip placed in a solution of Al(NO3)3, and the other has a nickel strip placed in a solution of NiSO4. The overall cell reaction is
2Al(s)+3Ni2+(aq)?2Al3+(aq)+3Ni(s)
1. What is being reduced?
2. Write the half-reactions that occur in the two electrode compartments.
anode reaction:
cathode reaction:
In: Chemistry
How many grams of Na2CO3 should be mixed with 5.00 g of NaHCO3 to produce 100 mL of buffer with a pH of 10.00? What volume of 0.01 M NaOH must be added to this solution to achieve a pH of 11.25? (pKa1 is 6.35; pKa2 is 10.53)
In: Chemistry
Using energy level diagrams, predict the relative stability of a Br2 molecule as well as the first excited state.
In: Chemistry
1a) A sample of a new cleaning product, "Joe's Famous Bleach Cleaner," with a mass of 59.0 g , was diluted with an acetic acid solution containing excess I−. A small amount of starch indicator solution was then added, turning the solution a deep bluish-purple. The solution was then titrated with 0.190 M sodium thiosulfate, Na2S2O3, containing the ion S2O32−. A volume of 45.0 mL of sodium thiosulfate, the titrant, was needed to turn the solution colorless. What is the percentage composition by mass of NaClO in the bleach product?
1b) A stainless steel alloy is to be analyzed for its chromium content. A 3.50 g sample of the steel is used to produce 250.0 mL of a solution containing Cr2O72−. A 10.0-mL portion of this solution is added to BaCl2(aq). When the pH of the solution is properly adjusted, 0.145 g BaCrO4(s) precipitates. What is the percent Cr, by mass, in the steel sample?
In: Chemistry