Consider a helium ion He+.
a) Find the ratio between the ionization energy of the H atom and and the He^+ ion.
b) How does the Bohr radius, we defined for H atom, differ for He^+ ? Using the Bohr radius of He^+ and the representation of the ground state wave function for the H atom, write the ground state wave function for the He^+.
c) Find the average distance of a 1s electron from a nucleus in He+ ion. How does it compare with the Bohr radius you found in (b) for H atom and He^+ ion?
d) Find the most probable value of r characterizing the distance between a 1s electron and the nucleus in the He^+ ion. Compare your answer with (c) and discuss a physical meaning of obtained results.
e) Find the average distance of 2pz electrons from a nucleus in He+ ion. Compare your results with those for a 1s electron in (c). Are you surprised by the answer?
f) How your answer in (e) would be different, if you find the average distance of 2px electrons, instead of pz?
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The pH of a 0.392 M solution of the conjugate base, A-, of a weak acid, HA, is 11.60. What is the Kb for A-?
Please show work
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Other then a COUNTERFEIT DETECTION PEN , HOW chemistry is being used in money detection and WHAT other chemical application can be used to prevent counterfeit currency from circulation.
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At 1177 K the partial pressures of an equilibrium mixture of H2O, H2 and O2 are 0.0340, 0.0035 and 0.0013 atm, respectively. Given that the chemical equation for the equilibrium is, 2 H2O(g) <----> 2 H2(g) + O2(g) calculate Kp and Kc.
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1) Oxidation refers to...
a) an increase in Oxidation number. b) a decrease in Oxidation
number. c)an increase in atomic number. d) an increase in mas.
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1. The molar mass of a compound is 126 g/mol, and it's empirical formula is C2H2O. What is compound's molecular formula?
2. A compound consist of 26.18g Si and 29.82g O. Calculate its empirical formula?
3. Calculate the empirical formula of the compound that consist of 70.4%F and 29.6%O.
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C: CaCO3 (s) ----> CaO (s) + CO2 (g) delta H= +178
kJ/mol
D: PCl3 (g) + Cl2 (g) -----> PCl5 (g) delta H= - 88 kJ/mol
Classify these changes as either LEFTWARD SHIFT, RIGTHWARD SHIFT,
or NO SHIFT
System C increase temperature
System C decrease temperature
System D increase temperature
System D decrease temperature
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What products result when calcium carbide is combined with water?
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Molarity of standard NaOH solution: x/1 H 2/3 Unknown + 2/3 NaOH -> 2/3 H2O +Na 2/3 Acetate
| Vinegar: | Titration 1 | Titration 2 | Tirtration 3 |
| Initial V of Acid | .01 mL | 5.56 mL | 11.32 mL |
| Final V of Acid | 5.56 mL | 10.71 mL | 16.02 mL |
| Inital V of Base | .01 mL | 27.12 mL | 3.01 mL |
| Final V of Base | 22.23 mL | 44.71 mL | 24.90 mL |
Unknown Acid code and number of reactive hydrogens: H+3
| Unknown Acid | Titration 1 | Titration 2 (Error) | Titration 3 | Titration 4 |
| Mass of Acid | .1024 g | .1028g | .1021g | .1023g |
| Initial V of Base | 24.90 mL | 37.80 mL | 45.5 mL | 9.24 mL |
| Final V of Base | 37.80 mL | 45.5 mL | 9.24 mL | 17.80 mL |
4. Find the molarity of the vinegar for each of your three vinegar titrations, then find the average molarity of the acid.
5. Find the percent deviations for your three vinegar molarities for the vinegar titrations.
6. From the moles of acetic acid for each vinegar titration,
find the mass of acetic acid for that titration
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A fire extinguisher has a pressure of 12 atm at 25∘C.What is the final pressure, in atmospheres, when the fire extinguisher is used at a temperature of 63 ∘C, if Vand n are constant?
P=
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What are the rules for net ionic equations? I know you must follow the solubility chart, but I'm confused about the other aspects. When the compound is solid, gas or liquid, I don't break apart the compound right? Unless the compound is a strong acid and base? I already know the steps of finding the net ionic equation. I'm just not sure about the rules. So if you could provide an example for the different reactions, can you also include the differences when using the rules?
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In the williamson ether synthesis of n-butyl methyl ether from 1-bromobutane, sodium, and ethanol, how could the purity as well as the percent yield of the product be improved?
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Consider the following reaction:
CO(g)+2H2(g)⇌CH3OH(g)CO(g)+2H2(g)⇌CH3OH(g)
The reaction between COCO and H2H2 is carried out at a specific
temperature with initial concentrations of COCO = 0.32 M
M and H2H2 = 0.52 M M. At equilibrium, the concentration
of CH3OHCH3OH is 0.15 M M.
Find the equilibrium constant at this temperature.
Express your answer using two significant figures.
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Please answer and exaplain ALL 4 parts! Thank you!
A 3.00 mL aliquot of 0.001 M NaSCN is diluted to 25.0 mL with 0.2 M Fe(NO3)3 and 0.1 M HNO3.
1. How many moles of SCN- are present?
2. If all of the SCN- is complexed with Fe3+ to form FeNCS2+, what is the molar concentration of FeNCS2+?
3. For preparing a set of standard solutions of FeNCS2+, the equilibrium molar concentration of FeNCS2+ is assumed to equal the initial molar concentration of the SCN- in the reaction mixture. Why is this assumption valid?
4. The blank solution used to calibrate a spectrophotometer is 10.0 mL of 0.2 M Fe(NO3)3 diluted to 25.0 mL with 0.1 M HNO3. Why is this solution preferred to simply using de-ionized water for the calibration?
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