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1answer
21 views

What are the molecular orbitals of the hypothetical linear H₃⁺ molecule?

What would be the wave function of the lowest energy molecular orbital of a hypothetical linear H3+ molecule? According to the LCAO method, I feel the lowest energy MO will be 1s(A) + 1s(B) + 1s(C). ...
1
vote
1answer
25 views

How do I calculate the density of propane assuming an ideal gas?

Assuming an ideal gas, calculate the density in $\mathrm{g/cm^3}$ of propane, $\ce{C3H8}$ at $0.000~^\circ\mathrm{C}$ and $1.000~\mathrm{atm}$. (3 significant figures) I have figured out that I ...
0
votes
1answer
71 views

Chemistry Quiz Question [on hold]

A solution is created by measuring 3.90 x 10-5 moles of $\ce{NaOH}$ and 5.85 x 10-4 moles of $\ce{HCl}$ into a container and then water is added until the final volume is 2.00 L. What is the pH of ...
1
vote
1answer
21 views

What other factors can make a compound dissolve into water?

I am doing some homework just right now, and I encountered this problem. I know that the polarity of the water molecules allows them to be a solvent for a variety of polar species or even species ...
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votes
1answer
34 views

How to calculate the heat of dissolution from a calorimeter experiment?

A $1.50~\mathrm{g}$ sample of $\ce{KCl}$ is added to $35.0~\mathrm{g}$ $\ce{H2O}$ in a Styrofoam cup and stirred until dissolved. The temperature of the solution drops from $24.8$ to ...
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0answers
27 views

Some help with calculations and solutions

I got this assignment from my teacher to prepare for a small research project. However, I have no idea what I'm supposed to do (her teaching isn't the greatest) and how to continue from here. My buddy ...
1
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0answers
18 views

Ratio of MbO2/Mb in a satured solution of dissolved oxygen from dry air

What is the ratio of $\ce{MbO2/Mb}$ if the solution is saturated with air? Details of the question: \begin{align} &&\ce{Mb + O2 (aq) &-> MbO2}\\ &&\Delta G' &= ...
-3
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0answers
21 views

How to calculate how much glucose has been burnt to form a certain amount of carbon dioxide? [on hold]

If we monitor the production of $\ce{CO2}$ and see that $5~\mathrm{g}$ have been produced, how much glucose has been consumed? How much energy has been released?
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0answers
19 views

Which is the most basic oxide among group 15 oxides? [on hold]

Of $\ce{N2O3}$, $\ce{N2O}$, $\ce{P2O3}$, $\ce{Bi2O3}$ which oxides is the most basic? And how to determine the order of increasing basic nature for oxides of any group?
5
votes
1answer
35 views

Percent composition, maybe?

I've attempted to solve this problem with percent composition, but it says the answer is wrong. Is it a PV=nRT problem, and if so, can I use the units as they are given? A 0.02867 g sample of gas ...
0
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0answers
12 views

Based on the table of standard reduction potentials indicate whether or not the following reactions would occur in the direction written

Based on the activity series or (table of standard reduction potentials), indicate whether or not the following reactions would occur in the direction written. Don't worry about what the activity ...
-2
votes
0answers
18 views

How to find the mass of each products produced [on hold]

$$\ce{16 HCl(aq) + 2 KMnO4(s) 2 MnCl2(aq) + 8 H2O(l) + 5 Cl2(g) + 2 KCl(aq)}$$ The reaction of hydrochloric acid with potassium permanganate is described above. 153.33 g of hydrogen chloride is ...
0
votes
1answer
14 views

I need to calculate the chemical formula for a substance from its amu

A compound is 54.53% C, 9.15% H, and 36.32% O by mass. What is its empirical formula? To this I got the answer C(2)H(4)O. Then the next part of the question asks,"The molecular mass of the compound is ...
-4
votes
1answer
53 views

which of the following electron configurations is most likely to result in an element that is relatively reactive [closed]

a. An energy level that is one electron away from being filled b. A full filled energy level c. Have only one electron in the outermost subshell d. Both b and c
-1
votes
1answer
19 views

A mixture of 0.140 moles of C is reacted with 0.117 moles of O2 in a sealed, 10.1 L vessel at 500 K, producing a mixture of CO and CO2 [closed]

$0.140$ moles of $\ce {C}$ reacts with $0.117$ moles of $\ce {O2}$ in a sealed, $10.1~\mathrm{L}$ vessel at $500~\mathrm{K}$, producing a mixture of $\ce {CO}$ and $\ce {CO2}$. The total pressure is ...
0
votes
1answer
13 views

A 4.00 L sample of gas is cooled from 67 °C to a temperature at which its volume is 2.60 L [closed]

A $4~\mathrm{L}$ sample of gas is cooled from $67~\mathrm{°C}$ to a temperature at which its volume is $2.6~\mathrm{L}$. What is this new temperature? Assume no change in pressure of the gas.
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votes
3answers
32 views

Lewis structures of Chemistry

How do you draw the lewis structure of $\ce {CS2}$ (carbon disulfide). I think I have the right answer but it says I don't
1
vote
1answer
25 views

Identifying Compound from the given information

A white solid is either $\ce{Na2O}$ or $\ce{Na2O2}$. A piece of red litmus paper turns white when it is dipped into a freshly made aqueous solution of white solid. Identify the ...
-1
votes
0answers
26 views

Calculate the percentage of ZnO and Fe_2O_3 [closed]

Calamine, which is used for relief of skin irritations, is a mixture of zinc and iron oxides. A $1.022-\ce{g}$ sample of dried calamine was dissolved in acid and diluted to $250.0 \,\ce{ml}$. ...
0
votes
0answers
39 views

How to get C2H6O2 from CH4? [closed]

So I am supposed to get $\ce{C2H6O2}$ from $\ce{CH4}$ ($\ce{CH4 -> C2H6O2}$). $\ce{CH4}$ has to react with some inorganic reagents in order for it to make $\ce{C2H6O2}$. We also have to find out ...
-1
votes
0answers
14 views

What is ΔH for the reaction [closed]

42-Given this data $\mathrm{AZ_3} \to\mathrm{\frac12 A_2 + \frac32 Z_2}$ , $Δ\mathrm{H} = 46\, \mathrm{kJ}$ , $\mathrm{2Z_2 + X_2}\to\mathrm{2Z_2X}$, $ΔH =-484\, \mathrm{kJ}$. What is $\mathrm{ΔH}$ ...
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votes
0answers
16 views

which reaction corresponds to the value of enthalpy of formation ΔHt for Al2O3(S)? [closed]

which reaction corresponds to the value of enthalpy of formation ΔHt for Al2O3(S)? (A) Al2(g)+O3(g)---> Al2O3(S) (B) 2Al(S)+3O(g)---> Al2O3(S) C) 4Al(s)+3O2(g)--->2Al2O3(S) (D) 2Al(s)+3/2O2---> ...
-1
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0answers
18 views

Calculating heat from ΔH [closed]

I am stuck in this problem please help me. what is the heat $Q$, when $25~\mathrm{g}$ of acetonitrile $\ce {CH3CN}$ reacts completely with excess water? $\ce {CH3CN(l) + 2H2O(l)->CH3COOH(aq) + ...
0
votes
1answer
23 views

what mass of Ca(OH)2 would be required to neutralize 120.0 mL 0f 0.350 M HCLO4? [closed]

Please help me in this question what mass of $\ce {Ca(OH)2}$ would be required to neutralize $ 120~\mathrm{mL}$ 0f $0.35~\mathrm{M}$ $\ce {HClO4}$ ? $\ce {2 HCLO4 + Ca(OH)2 ->Ca(ClO4)2 + 2H2O}$
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1answer
20 views

Find the percentage yeild

Plz help me i am totally confused when 8.70 g Al reacted with excess O2, 12.8 Al2O3 was obtained, what was the percent yield? Here is the balance equation 4Al+3O2--2Al2O3
0
votes
1answer
10 views

Specific heat capacity of two different metals

Tow metal sample, $X$ and $Z$, of the same mass and initially at $25 °C$, are heated so that each metal receives the same amount of thermal energy, which metal will have the highest final temperature? ...
0
votes
1answer
15 views

what volume of water must be added to 28.0 mL of 1.25 M FeCl3 to prepare a 0.650 M FeCl3 solution?

Help me please. What i tried is 1.25/0.650*28=53.8 is that correct?
2
votes
2answers
24 views

Source for Rf-Values especially 1-phenylazo-2-naphthol

So i have sythesized 1-phenylazo-2-naphthol in my laboratory tutorial and have to analyze it. So i've done a TLC of it: solvent Ethanol, eluent: Toluene. Stationary phase: Silica gel plate. My only ...
1
vote
0answers
27 views

Determine the free energy when you have present in a 2.00 L flask: 8.0 atm pressure of NH3 (g) and 4.0 atm pressure of N2(g)

I don't know what to do to find the of free energy when you have present in a 2.00 L flask: 8.0 atm pressure of NH3 (g) and 4.0 atm pressure of N2(g). This is the table given: Cu(s) ΔHf° (kJ/mol) = ...
1
vote
2answers
49 views

Symmetry representations for CH3CN

Can anybody share the symmetry labels for acetonitrile ($\ce{CH3CN}$), please? I mean I to assign the symmetry labels to orbitals of acetonitrile
-1
votes
0answers
20 views

How long for balloon filled with Ar gas to empty? [closed]

At $385~\mathrm{K}$, it takes $108~\mathrm{s}$ for a $1~\mathrm{L}$ balloon filled with $\ce {Ne}$ gas to empty. How long would it take for the same balloon filled with $\ce {Ar}$ gas to empty at ...
-1
votes
0answers
19 views

How to determine the best solvent for sodium chloride? [closed]

What is the best solvent for $\ce{NaCl}$? $\ce{C2Cl6}$ $\ce{HCl}$ $\ce{BCl3}$ $\ce{PCl5}$ I believe it is 2, but I'm not sure.
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0answers
22 views

Question about chemistr [closed]

Could you please write me the word equation of a reaction involving alcohol, alkenes and alakanes and draw out the formulas of the products and reactants?
0
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3answers
59 views

Which sample contains the greatest number of atoms?

Which has the greatest number of atoms from the following samples, given 1 gram of each: 1) sodium phosphate ($\ce{Na3PO4}$) (MM : 163.94) 2) sodium phosphide ($\ce{Na3P}$) (MM:99.94) 3) potassium ...
-3
votes
1answer
36 views

Structure of XeF4 [closed]

How can we get the structure of $Xe F_{4}$ using the concept of hybridization and number of lone pairs.
-3
votes
2answers
59 views

Lewis structure of Carbon Suboxide [closed]

What is the proper Lewis structure for Carbon Suboxide ($C_{3}O_{2}$).
0
votes
1answer
34 views

Explain why 2-methyl-1cyclohexanone slowly loses its optical activity at the presence of a dilute acid using structures and reactions [closed]

Explain why 2-methyl-1cyclohexanone slowly loses its optical activity at the presence of a dilute acid using structures and reactions Could you help me answer this question?
-1
votes
0answers
28 views

What is the heat required for a fluorocarbon to be converted from a liquid to a gas? [closed]

The fluorocarbon compound $\ce{C2Cl3F3}$ has a normal boiling point of $47.6~^\circ\mathrm{C}$. The specific heats of $\ce{C2Cl3F3(l)}$ and $\ce{C2Cl3F3(g)}$ are $0.91~\mathrm{J/g⋅K}$ and ...
-2
votes
2answers
99 views

Predict the standard potential at 310 K for the cell constructed from the hydrogen electrode and metal-insoluble salt electrode

I've run into trouble on this question Predict the standard potential at 310 K for the cell constructed from the hydrogen electrode and metal-insoluble salt electrode $\ce{Ag(s)|AgCl(s)|Cl-}$. ...
1
vote
1answer
29 views

Differentiating between two ionic solids : CaCO3 and SnO2

As part of a lab in chemistry we have to identify 6 different substances from a list of 15 by testing them for both physical and chemical properties (magnetism, solubility, etc.). I'm having trouble ...
0
votes
1answer
9 views

Quick Stoich & Gasses

I have a quick question in Stoich and Gasses, I however could not get any far, any answer will be appreciated. Thank You. A sample of $\ce{Pb(NO3)2}$ is heated, yielding $\ce{O2, NO2\ gas,\ and\ ...
1
vote
1answer
37 views

How to calculate the activation energy of diffusion of carbon in iron?

At room temperature, $298~\mathrm{K}$, the diffusivity of carbon in iron is $9.06\cdot 10^{-26}\frac{m^2}{s}$. At $573~\mathrm{K}$ the diffusivity is $1.66\cdot 10^{-15}\frac{m^2}{s}$. What is ...
4
votes
1answer
54 views

How to Determine Acid Strength?

The correct answer is E, but I do not understand why :( Shouldn't (v) have the lowest pKa since it does not have a carboxyl group making it a strong acid? How do we determine the strength of acids?
4
votes
2answers
51 views

Factors of London Forces

In class we learnt that the London forces become stronger as the relative molecular mass increases. Not just as in organic chemistry but in things like the halogens. However, as I understand, the ...
0
votes
1answer
34 views

Gas Stoichiometry & Ideal Gas Law

I need a little help with one of the problems below. Any help on the problem below will be appreciated. I don't want to sound like an idiot, I will also provide my work. Solid $\ce{NaHCO3}$ ...
1
vote
1answer
57 views

Calculating the concentration of salt water

$23.4\text{ g}$ of $\ce{NaCl}$ are dissolved in $100\text{ g}$ of water. Calculate concentration of salt in the solution. Here's my work: Number of moles of salt is $0.4\text{ mol}$ Volume of ...
1
vote
3answers
40 views

Why is the dipole moment of ethyl-chloride larger than that of vinyl-chloride?

The dipole moment of ethyl chloride is 2.05 and vinyl chloride is 1.44. Why is this true? In my point of view dipole moment of latter should be greater due to the hyperconjugative effect. But ...
1
vote
1answer
21 views

What will happen to the entropy and free energy of the gasses when the partition is removed?

Consider a container of volume $ 5.0$ L that is divided into two compartments of equal size. In the left compartment there is nitrogen at $1.0$ $atm$ and $25 °C$; in the right ...
0
votes
3answers
54 views

Is this poor wording for a chemistry question? Does it require a simple answer or not?

A 2.00 g sample of limestone (calcium carbonate) was dissolved in hydrochloric acid and all the calcium present in the sample was converted to $\ce{Ca^{2+}(aq)}$. Excess ammonium oxalate ...
2
votes
1answer
31 views

Disproportionation Reactions of the Halogens: Writing balanced net ionic equations for four reactions. See details

I first conducted the following reactions, each in separate test tubes: $\ce{NaBr}$ + $\ce{H2SO4}$ + $\ce{NaBrO3}$ $\ce{KI}$ + $\ce{H2SO4}$ + $\ce{KIO3}$ ...with water and dichloroethane added ...