Do you predict that maltose will reduce cupric ion in Fehling
In: Chemistry
For the reactions shown below, we added 3.75 mL of 0.0450 M Na2S to a test tube containing one of the two cations (Cu2+ or Cd2+) and recovered 0.0161 g of precipitate.
Cu(NO3)2(aq) +
Na2S(aq) → CuS(s) + 2
NaNO3(aq)
Cd(NO3)2(aq) +
Na2S(aq) → CdS(s) + 2
NaNO3(aq)
How much precipitate in moles would be recovered theoretically
if the ion was Cu2+? (Enter an unrounded value. Use at
least one more digit than given.)
mol
How much precipitate in moles would be recovered theoretically if
the ion was Cd2+? (Enter an unrounded value. Use at
least one more digit than given.)
mol
How much precipitate in grams would be recovered theoretically if
the ion was Cu2+?
g
How much precipitate in grams would be recovered theoretically if
the ion was Cd2+?
g
Based on the precipitate amount recovered, which of the two ions
was in the unknown?
Cu2+
Cd2+
In: Chemistry
Calculate the nuclear binding energy in mega-electronvolts (MeV) per nucleon for 179Hf if its nuclear mass is 178.946 amu.
In: Chemistry
A 67.2 g sample of a gold and palladium alloy contains 2.85×1023 atoms . What is the mass percentage of the gold and palladium?
In: Chemistry
for the titration of 10.0 ml of .15 M HNO2 aqueous solution (Ka=7.2x10^-4) using 2.5 M NaOH aqueous solution, consider the following points of the titration: A: Initial pH of .15 M HNO2 aqueous solution B: .1 mL added base C: 1/2 equivalence point D: Equivalence point E Excess base (assume added 100.0 mL of base)
Set up the init mol, final mol, total volume, and ICE table for points B and D only:
Point B:
Titration equation:
init mol:
(assume reaction goes to completion)
final mol:
total volume:
flip reaction equation:
I:
C:
E:
Point D:
Titration equation:
init mol:
(assume reaction goes to completion)
final mol:
total volume:
flip reaction equation:
I:
C:
E:
In: Chemistry
Molar solubility of copper hydroxide in pure water, taken into account that water is adding hydroxide into the solution. Ksp=[Cu^2+][OH^-]^2 = 4.8x10^-20
(x) (1.0x10^-7 +2x)^2 = 4.8x10^-20
In: Chemistry
1. Why is that during alpha emission, the atomic number decreases by two, and the mass number decreases by four? In your answer yu should consider what alpha particle is?
2. In beta emission, the atom loses an electron, yet the atomic increase by one and the mass number stays the same. How is this possible? It may help if you consider what happen to the number of neutrons and protons.
3. if an element is bombarded by an neutron and subsequently emits a gamma ray, then it follows that the mass number will increase by one. How is it then, the atomic number remains unchanged?
In: Chemistry
Part A
A 3.00-L flask is filled with gaseous ammonia, NH3. The gas pressure measured at 25.0 ∘C is 2.05 atm . Assuming ideal gas behavior, how many grams of ammonia are in the flask?
Express your answer to three significant figures and include the appropriate units.
Part B
If 1.00 mol of argon is placed in a 0.500-L container at 28.0 ∘C , what is the difference between the ideal pressure (as predicted by the ideal gas law) and the real pressure (as predicted by the van der Waals equation)?
For argon, a=1.345(L2⋅atm)/mol2 and b=0.03219L/mol.
Express your answer to two significant figures and include the appropriate units.
In: Chemistry
Discuss the thermodynamic driving force of micelles and bilayer membranes.
In: Chemistry
In: Chemistry
What is the limiting reagent in esterification using isopentyl alcohol and acetyl chloride to make isopentyl acetate? Prove your answer with limiting reagent calculations.
Used 200 uL of isopentyl alcohol, 800 uL of acetyl chloride in the experiment.
In: Chemistry
In: Chemistry
The enthalpy change under standard conditions for which of the reactions below would be equal to the ∆H°f of NaOH(s)? (A) Na(s) + H2O(l) NaOH(s) + 1/2 H2(g) (B) Na(s) + 1/2 O2(g) + 1/2 H2(g) NaOH(s) (C) Na(s) + 1/2 H2O2(l) NaOH(s) (D) Na+(aq) + OH–(aq) NaOH(s) please explain why you chose that answer and why the other answers are wrong. If it has to do with them being in their standard states, how do I know what the standard states of the elements are.
In: Chemistry
When light of wavelength equal to 364 nm strikes a metal, the kinetic energy of the ejected electron is 4.12 × 10-19 J. What is the work function of the metal?
In: Chemistry
The reaction
Zn(NO3)2 + 4NaOH ---> Zn(OH)42- + 2NO-3 + 4Na+
If 25 mL of a 0.10 M Zn(NO3)2 is added to 10.0 mL of 0.65 M NaOH and at equilibrium the concentration of Zn(OH)42- is found to be 0.012 M, find Kc
In: Chemistry