CHEMISTRY COMMUNITY

Yiwei Zhou 2I

14.119 One stage in the extraction of gold from rocks involves dissolving the metal from the rock with a basic solution of sodium cyanide that has been thoroughly aerated. This stage results in the formation of soluble Au(CN)2- ions. The next stage is to reduce gold to the metal by the addition of z...

Yiwei Zhou 2I

Q: Rank the following in order of increasing oxidizing power.

a).Mn,Ag,Ti

Could someone answer this question and also explain the solving process？
Thanks so much!

Yiwei Zhou 2I

Aqueous solutions of (a) Mn2; (b) Al3; (c) Ni2; (d) Au3 with concentrations of 1.0 molL1 are electrolyzed at pH 7. For each solution, determine whether the metal ion or water will be reduced at the cathode. What is the standard reduction potential of water? 2H2O + 2e- = H2 + 2OH- -0.83V ...

Yiwei Zhou 2I

14.25 Arrange the following metals in order of increasing strength as reducing agents for species in aqueous solution: (a) Cu, Zn, Cr, Fe; (b) Li, Na, K, Mg; (c) U, V, Ti, Al; (d) Ni, Sn, Au, Ag When we compare the standard reduction potential of Cu, which data should we use? Why? (Cu+) + (e-) = Cu ...

Yiwei Zhou 2I

"Calculate the equilibrium constant at 25 C and at 150 C for each of the following reactions, using data available in Appendix 2A"

When can we calculate the equilibrium constant deltaG with Gibbs Free Energy of Formation in Appendix 2?
When can't we?

Yiwei Zhou 2I

I think that specific heat capacities will be given in the constants and formulas sheet or be mentioned in the question.

Yiwei Zhou 2I

8.113 Water gas is an inexpensive, low-grade fuel that can be made from coal. (a) Is the production of water gas exothermic or endothermic? The reaction is C+H2O=CO+H2 The solution manual solves it by using standard enthalpy of formation. Can we solve it by using bond enthalpies? (I tried but the re...

Yiwei Zhou 2I

For the production of 1.00 mol H2, you have 1/3 mol CH4, 1/3 mol H20, and 1/3 mol CO2 produced. So the net mole of gas is 2/3 mol.

Yiwei Zhou 2I

I think we would be given certain bond enthalpies value instead of a whole chart

Yiwei Zhou 2I

It means that in a given heat amount, one with lower heat capacity changes the temperature more rapidly than the one with higher heat capacity.

Yiwei Zhou 2I

Because 4 hydrogen atoms are bounded on C atom so the bond enthalpy should be multiplied by 4. You can also count every bond, broken or not, in the reactants and the products that it takes less time to think about the bond breaking and forming process.

Yiwei Zhou 2I

12.115 Acetic acid is used as a solvent for some reactions between acids and bases. (a) Nitrous acid and carbonic acids are both weak acids in water. Will either of them act as strong acid in acetic acid? Explain your answer. (b) Will ammonia act as a strong or weak base in acetic acid? Explain your...

Yiwei Zhou 2I

250.0 means it is a 250.0-mL volumetric flask. We need to divide the moles by volume to get the H3O+ concentration.

Yiwei Zhou 2I

22. A protein like histidine can bind at one site to the heme complex iron to from myoglobin. How many O2 molecules can myoglobin bind? How many myoglobin form a hemoglobin?

Can someone explain this question for me? Thanks so much!

Yiwei Zhou 2I

It is a Bronsted acid/base reaction if H+ is referred as a proton.

Yiwei Zhou 2I

A conjugate acid contains one more H atom and one more + charge than the base that formed it. A conjugate base contains one less H atom and one more - charge than the acid that formed it. Take a example: HCO₃⁻ + H₂O → H₂CO₃ + OH⁻ base + acid → Conj A + Conj B HCO₃⁻ becomes H₂CO₃. It has one more H a...

Yiwei Zhou 2I

What is the difference between K and Kc+ in the Table 11.2 in the textbook?

Yiwei Zhou 2I

Cl2's dissociation has a smaller equilibrium constant so Cl2 is more stable.

Yiwei Zhou 2I

Though it is not an assigned problem, to calculate K you need the format of deltaG = - RTlnK.
The Gibbs free energy of formation of 1 mol NO can be found from appendix 2 in the textbook.

Yiwei Zhou 2I

Single, double and triple bonds count as one region of electron density.
Paired elections or an unpaired electron also count as one region of electron density.

Yiwei Zhou 2I

Hybridization is actually the way we explain the VSEPR model. We first discover some molecular geometry. For example, the C-H bond in CH4 has equal length, but the valence electrons are not in the same energy level; and later we use hybridization as an explanation that hybrid orbitals are assumed to...

CHEMISTRY COMMUNITY

Search found 21 matches

14.119

Questions in the second test

TEXTBOOK 14.57

TEXTBOOK 14.25

TEXTBOOK 11.83

Re: Heat capacity [ENDORSED]

Textbook 8.113

Re: 8.117

Re: Bond enthalpies

Re: Heating curves

Re: 8.73.b

Textbook 12.115 [ENDORSED]

Re: 12.27 part B

Question on practice exam [ENDORSED]

Re: H+ as Lewis acid/base [ENDORSED]

Re: Identifying Conjugates

Question about Table 11.2 in textbook

Re: 45 part c

Re: Problem 11.29

Re: Electron density question

Re: Purpose of hybridization [ENDORSED]