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0answers
11 views

Products of haloform reaction of acetylacetone?

I searched a lot to find the products of the haloform reaction of acetylacetone, but I didn't find any result. What are the products of the haloform reaction of acetylacetone?
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1answer
13 views

Molecular weight determination from freezing point depression

I have these two questions in my lab manual and I don't know how to approach them. 1) Which is the better solvent for molar mass determinations by freezing point depression, benzene or cyclohexane? ...
-2
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0answers
39 views

Bond Strength of Carbon bonding

Please sort these bonds in decreasing order of their bond strengths... 1.$\ce{C=O}$ 2.$\ce{C#N}$ 3.$\ce{N#N}$ 4.$\ce{C-C}$ 5.$\ce{C-H}$ My attempt to the question - C=O>N≡N>C≡N>C−C>C−H Is ...
-1
votes
0answers
27 views

Alkyne's + Sodium or Soda Amide [duplicate]

What is the reaction when But-2-yne Reacts with $\ce{Na}$ or $\ce{NaNH2}$? According to me it should be no reaction.. but please correct me. Also what happens when But-1-yne undergoes the same ...
2
votes
1answer
18 views

How to calculate valence factor (n-factor) for a element?

Suppose I am given some reaction in which $$\ce{C6H12O6 -> CO2}$$ and I want to calculate n-factor for this reaction to ultimately calculate equivalent weight of carbon for this reaction. Since ...
-1
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0answers
20 views

The chemical shift of two protons in o-position in anisole [on hold]

The chemical shift of the two protons in o-position in anisole (methoxybenzene)compound is? 1)equal the chemical shifts of all the protons in the benzen ring 2)less than the chemical ...
1
vote
1answer
36 views

Reactions of alkynes and Sodium or soda amide [on hold]

What happens when alkynes react with Sodium or soda amide? Does it liberate hydrogen so does it prove that alkynes are acidic? What happens when But-1-yne and but-2-yne react with Sodium and soda ...
1
vote
3answers
32 views

Effect of pressure on solubility of salts

The volume of certain saturated solution is greater than the sum of the volumes of the water and salt from which it is made. On increasing pressure solubility of this salt (a) Increases ...
2
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1answer
20 views

Decomposition of hexaurea-chromic-chloride-trihydrate

I am sitting over a TG diagram of the decomposition steps of hexaurea-chromic-chloride-trihydrate ($\ce{[Cr(CO(NH2)2)6]Cl3 \cdot 3 H2O}$) and cannot really make sense of the products it might ...
2
votes
1answer
53 views

If 2-chloro-3-methyl-3-phenyl butane undergoes SN1 then what will the major product and why? [on hold]

If 2-chloro-3-methyl-3-phenylbutane undergoes $\mathrm{S_{N}1}$ then what will the major product be ? Will methyl group shift or phenyl group shift? I know that phenyl shift will occur..but i want to ...
-2
votes
0answers
8 views

Ph change in buffer solution [on hold]

I have a 50 mM Sodium acetate buffer pH 5. How do I calculate how much NaOH that is needed to change the pH to 8?
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0answers
11 views

Stoichiometry of biomass production [on hold]

I'm given a reaction as follows: $\ce{16CO2 + 16NO3- + HPO4^{2-} + 122H2O + 18H+ + Trace~elements -> C106H263O110N16P1 + 138O2}$ Assuming that P removal from euphotic zone is 6 microgram/L ...
0
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0answers
17 views

Calculating enthalpy of formation [on hold]

Ethanoic acid (HC2H3O2) may be produced from ethyne (C2H2) by the following overall reaction: 2 C2H2(g) + 2 H2O(l) + O2(g) ---> 2HC2H3O2 (l) Calculate Ho for the production of ethanoic acid using the ...
-3
votes
0answers
20 views

Calculation of acid and base concentrations [on hold]

what are the $[\ce{OH-}]$ and $[\ce{H+}]$ in a $4.0\cdot10^{-3}\,M \ce{HCl}$ solution? What are the $[\ce{OH-}]$ and $[\ce{H+}]$ in a $0.043\,M \ce{KOH}$ solution?
2
votes
1answer
37 views

How to find partial pressures from a given equilibrium constant Kp?

I had following question on my quiz and but I answer it wrong because I can't seem to solve it. It is related to finding equilibrium constant. Question: For the following reaction, at ...
1
vote
1answer
35 views

Does this equation balance?

$$\ce{CaCO3 + 2H2O + Pb^{2+} -> Pb(CO3) + Ca(OH)2 + H2}$$ Does this equation balance? On the right you have lead with 2+ charge, whereas on the right its completely neutral. So my question is do ...
0
votes
1answer
59 views

Strongest oxidizing agents and reducing agent

I have to find out the strongest oxidizing agent and the strongest reducing agent in: $\ce{Cr(NO3)2(aq)}$ and $\ce{FeCl3(aq)}$. This is my current thinking: $\ce{Cr(NO3)2(aq)}$ Contains ...
2
votes
1answer
60 views

Organic Chemistry - Nucleophilic Substitution Reactions

What order of reactivity do you predict will be observed when each alkyl halide is mixed with sodium iodide in acetone? 1-Chlorobutane 1-Bromobutane 2-Chloro-2-methylpropane ...
-1
votes
0answers
21 views

Electrolysis of water and production of O₂ gas [closed]

Assuming that electrolysis is 100% efficient, 1 mole of gas=22.4dm^3 and 1 mole of e- = 100,000 C a. Write down the oxidation and reduction half-reactions of electrolysis of water b. Calculate the ...
2
votes
0answers
22 views

How to determine ortho/para substituents on the aromatic ring via NMR ?

I have no idea how to determine the substituents on the aromatic ring from NMR diagram. There is (might be ) a triplet on my NMR around 7.59-7.65ppm which has 4 hydrogens in the same environment. If ...
2
votes
1answer
40 views

How many moles NH₄Cl must be added to NH₃ to create buffer with pH=9?

In my textbook there is the following problem: How many moles of $\ce{NH4Cl}$ must be added to $2.0~\mathrm{L}$ of $0.10~\mathrm{M}$ $\ce{NH3}$ to form a buffer with $pH=9$? Assume the addition ...
0
votes
0answers
20 views

What is the initial concentration of [Pb2+] and [CO32-]? [closed]

$\ce{PbCO3}$ is another salt that barely dissolves in water. Ksp = 7.4 x 10-14 If 100.0 ml of 0.050 M $\ce{Pb(NO3)2}$ is mixed with 100.0 ml of 0.00100 M $\ce{Na2CO3}$, calculate the initial ...
4
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2answers
320 views

Learning about explosives

I was wondering why temperature regulation is an important factor in producing explosives. I know many are exothermic reactions but what would happen if you did not use an ice bath and allow the ...
3
votes
1answer
59 views

Formula of a cubic lattice

Question: In a cubic lattice of XYZ, X atoms are present at all corners except one corner which is occupied by Y atoms. Z atoms are present at face centres. What is the formula of compound? ...
0
votes
1answer
24 views

The change in enthalpy of carbon in diamond form to graphite is negative .This suggests that graphite should be more stable than diamond. is it true?

What I thought was that graphite has van derr waal forces while diamond has covalent forces so diamond should be more stable. but the melting point of graphite is more than diamond which implies that ...
-2
votes
1answer
33 views

Calculating Energy Change of Acetic acid [closed]

A 10.0 g sample of pure acetic acid (CH3COOH) is completely burned. The heat released from the combustion is used to warm 2.00 L of water from 22.3 ℃ to 39.6 ℃. Assuming no heat was lost to the ...
-2
votes
0answers
25 views

How to find the empirical formula and the molecular formula? [closed]

A compound contains 67g Barium and 33g of Hydrogen with true MW= 27.6 Octanes are gasolines containing 35% Carbon and 65% Hydrogen. True MW= 111 thank you so much
0
votes
1answer
33 views

how to determine the bond order using the Lewis structure

What are the steps to follow to determine which has a higher bond order say $\ce{CO}$ and $\ce{CO3^{2-}}$ by drawing the Lewis structure?
1
vote
1answer
60 views

How to calculate the bond energy of C-Cl?

$$\ce{C(s) + 2 Cl2 (g) -> CCl4 (g)}$$ \begin{align} \Delta{}H^\circ_\mathrm{f} (\ce{C(g)}) &= 121~\mathrm{kJ/mol}\\ \Delta{}H^\circ_\mathrm{f} (\ce{Cl (g)}) &= 716~\mathrm{kJ/mol}\\ ...
0
votes
1answer
39 views

What are the factors to be considered when comparing the bond length in different nitrogen oxygen species? [closed]

At what factors do we have to look when comparing the $\ce{N-O}$ bond length in the species $\ce{NO2+}$, $\ce{NO2-}$ and $\ce{NO3-}$? Is there a difference between bond angle and bond length?
1
vote
1answer
38 views

find percentage ionic character if electronegativity is given

Lets say that a in a compound A-B, electronegativity of A is x and that of B is y,what will be the percentage ionic character in terms of x and y? I have been taught that the percentage ionic ...
1
vote
1answer
31 views

Partial pressure and chemical equilibirum

Suppose I am given following reaction in vessel $$\ce{NH4HS_(s) <=> NH3(g) + H2S(g)} $$ $P_{\ce{NH3}}=P_{\ce{H2S}}=1\,\mathrm{atm}$ at Equilibrium , If volume is doubled at this instant then ...
2
votes
1answer
36 views

Solubility of Ca(OH)₂ as determined by experiment

For a lab I had to determine the solubility and $K_{sp}$ of $\ce{Ca(OH)2}$ by performing two different titrations. I am given the formula to find solubility in molarity it is as written below. ...
0
votes
1answer
20 views

How much water was absorbed? [closed]

Water is sometimes removed from the products of a reaction by placing them in a closed container with excess $\ce{P4O10}$ . Water is absorbed by the following reaction: $$\ce{P4O10 + 6H2O -> ...
0
votes
1answer
45 views

How to calculate the enthalpy of formation of hydrazine from tabulated values?

I've been given a problem asking: Estimate the standard enthalpy of formation of hydrazine, $\ce{N2H4(g)}$, from the following data. \begin{align} \Delta{}H_\mathrm{B}(\ce{H2}) &= ...
3
votes
2answers
100 views

Green and red crystals of [Ni(Ph2EtP)2Br2]

"From the reaction of $\ce{NiBr2}$ and $\ce{Ph2EtP}$, it is possible to isolate green and red crystals of $\ce{[Ni(Ph2EtP)2Br2]}$? A) coordination number and geometries of the complexes? B) ...
1
vote
1answer
27 views

Ratio of copper(II) ions to EDTA?

One question in a test I am preparing for is: What is the ratio of copper(II) ions to EDTA in a $\ce{[Cu(EDTA)]^{2-}}$ complex? I know that EDTA forms up to 6 coordinate bonds with the central ...
3
votes
0answers
28 views

What does the peak separation of carbon dioxide IR rotational-vibrational spectrum corresponds to and why?

Spectrum of $\ce{CO2}$ at $2349\space \mathrm{cm^{-1}}$ region For some other molecules (for example $\ce{CO}$) the peak separation corresponds to $2B$ (where $B$ is the rotational constant ...
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votes
1answer
28 views

Why does aluminium foil does not react with water molecules in a microwave? [closed]

Why does aluminium foil does not react with water molecules of food in a microwave?
0
votes
1answer
32 views

How to calculate to number of moles using the ideal gas law [closed]

Which quantity of N2 gas has a volume of 11.2 liters at STP? Select one: 1.00 moles 2.00 moles 14.0 grams 28.0 grams
5
votes
2answers
69 views

How much does the quality of glassware matter, really?

Discussing about the pros and cons of glassware from different manufacturers for chemistry experiments easily becomes a heated debate. Well, that's how it seems if you read the chemistry related ...
1
vote
1answer
81 views

How to calculate the solubility of AgCl in a MgSO₄ solution?

The solubility product of $\ce{AgCl}$ in water is given as $1.8\cdot10^{-10}$ Determine the solubility of $\ce{AgCl}$ in pure water and in a $0.25~\mathrm{M}$ $\ce{MgSO4}$ solution. I solve to the ...
0
votes
1answer
59 views

How do you find the pH of a solution from a density and weight percentage?

An $\ce{HCl}$ solution of density $\mathrm{1.19~g~ml^{-1}}$ has weight percentage of 38%. Find it's pH. Since there is no given volume I assume there is no way to solve this?
0
votes
1answer
17 views

How do you figure out the dissociation energy for ions?

Specifically $\ce{KF}$ into the $\ce{K+}$ and $\ce{F-}$ ions. I can find tables on the DE into atoms, but where would I go to find the DE between ions? I am also given that the bond length is ...
-1
votes
1answer
36 views

How to calculate the pH of a sodium fluoride and hydrogen fluoride aqueous mixture? [closed]

What is the pH of a solution that is $0.20~\mathrm{M}$ in $\ce{HF}$ and $0.40~\mathrm{M}$ in $\ce{NaF}$? $K_a = 7.2\cdot10^{-4}$ I am stumped on this question. Is the concentration greater in ...
0
votes
1answer
54 views

How much water evaporates In a vacuum before freezing?

I placed a container with 1000 grams (1 kg) of water at room temperature (20 degrees celsius) Inside a vacuum at 0.03 atm pressure. The water boiled for a few seconds then froze solid. I need to ...
3
votes
2answers
50 views

How to calculate the enthalpy change for the formation of ethylene epoxide from ethylene?

Question 4, iii.) in here: (iii) The equation for an important reaction of ethene is given below. I get everything up until the very end. We need to identify the bond enthalpies first: ...
0
votes
1answer
25 views

Why is the work done by gas expanding to space is 0 and not infinity?

Suppose there's a spaceship that has a hole in it. Gas is expanding through the hole from the spaceship to outer space (vacuum). According to pressure volume work ($P\Delta V$) the work done by the ...
1
vote
2answers
17 views

How to determine the sign of the enthalpy of formation?

During the formation of $\ce{Al2O3}$ from 5.4 grams of $\ce{Al}$ and enough oxygen, the temperature of 2Kg of water climbs by 20 degrees. What's the enthlpy of formation of $\ce{Al2O3}$ (per mole) ? ...
2
votes
0answers
22 views

How to calculate excess of the reagent for the reaction of potassium with nitrogen?

This is a problem from online Chem 11 course: $50.0~\mathrm{g}$ of potassium is reacted with $7.0~\mathrm{g}$ of nitrogen, according to the following equation $$\ce{6K + N2 -> 2K3N}$$ How ...