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0answers
31 views

Is aluminium a post-transition metal?

Certainly I know to which group of the periodic table does it belong, and the IUPAC Group 13 obviously comes after groups 3–11. But look: aluminium belongs to a short Period 3 where no transition ...
2
votes
1answer
64 views

Coordinate bonds between molecules

For the following question Which molecules react to form a dative/coordinate bond? A. $\ce{CH4}$ and $\ce{NH3}$ B. $\ce{C2H2}$ and $\ce{Cl2}$ C. $\ce{NH3}$ and $\ce{HF}$ D. $\ce{Cl2}$ ...
5
votes
1answer
235 views

Is the equation dG = Vdp − SdT valid only for a reversible process? Can it be applied for an irreversible one too?

In the derivation, we write: $$ \begin{align} G &= H - TS &\quad&\to&\quad \mathrm dG &= \mathrm dH - T\,\mathrm dS - S\,\mathrm dT \\ H &= U + pV &\quad&\to&\quad ...
-1
votes
0answers
13 views

Which of the following is not a characteristic of an intermediate compound? [closed]

(A) Their melting points are higher than those of pure metals. (B) They are very hard and hard. (C) They maintain the metallic conductivity. (D) They are chemically very reactive.
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votes
0answers
34 views

What are green house gases? [duplicate]

My question is about green house gases. How can identify which gas is a green house one. In addition , how can i recognise that a gas had polar and dipolar bonds?
0
votes
0answers
24 views

Polarisability of quantum coherent molecules [on hold]

I know that the polarisability is a measure of how an atom's electrons can be displaced from equilibrium by a nearby electric field. But if the molecules are quantum coherent like in ...
6
votes
1answer
94 views

How does the energy released during a bond formation typically manifest itself on atomic level?

Chemistry newb here. I've been reading about how energy is released when new chemical bonds are formed but it's hard to find info on how that typically manifests itself (besides that it's via heat). ...
0
votes
0answers
34 views

What is the total mass of oxides formed in this chemical reaction? [closed]

Sodium chromate reacts in an aqueous environment with metallic iron to form the oxides of chromium(3) and iron(3): 2H2O + 2Na2CrO4 + 2Fe <-> Cr2O3 + Fe2O3 + 4NaOH How can I find the total mass of ...
-4
votes
1answer
44 views

Find the masses of NaCO3 and NaHCO3 in a mixture of NaCO3/NaHCO3 by using titration data [closed]

I'm having difficulty finding answer for following question: ]2 I am having difficulty in solving the last part about finding in 1 litre I used $n_1v_1=n_2v_2$ to equate equivalent and find molarity ...
1
vote
3answers
56 views

Identify the type of structural isomerism

Question: My Approach: Since both the compounds have the same principal functional group, they can't be functional isomers. Obviously they are different compounds. Now options A and C are ruled out. ...
-9
votes
0answers
54 views

Hi can you please answer me as fast as possible? [closed]

1.If you take a mixture of Znso4 and cuso4 solutions in a beaker and a zinc rod and a copper rod are inserted in it will you get electricity? Give reason 2.A zn rod is dipped in 0.4 M Cuso4 solution, ...
2
votes
0answers
13 views

Does an electronegative atom which carries a negative formal charge withdraw electrons by induction?

Electronegative atoms withdraw electrons by their inductuve effect. Does this fact remain true even when they are heavily loaded with electrons through negative formal charge? Are these two ideas ...
-1
votes
2answers
89 views

Number of sterioisomers of 2,3,5,6-tetrachloroheptane [closed]

The answer given by Himanshu Pandey in the book Advanced Problems in Organic Chemistry, Chapter Isomerism, Page 76 is 10. But by calculating using the fundamental principle of counting and by viewing ...
0
votes
1answer
36 views

What are Mulliken atomic charges, and how are they computed?

I was reading about the self-consistent extended Hückel method (SC-EHT), and stumbled upon various formulae for the diagonal elements of the Hamiltonian matrix. I noticed that many formulae depend on ...
1
vote
2answers
52 views

Resonance and mesomeric effect [closed]

Can you please explain to me why are A and E not relevant resonance structures of the molecule F? And is B aromatic?
-1
votes
0answers
18 views

how are unequal bonds related to hybridization? [on hold]

in which of following molecule all bonds are not equal? (A) XeF4 (B) BF-4 (C) C2H4 (D) SiF4 i need a clarity in these type of questions, i have found the hybridisation of each molecule but i am ...
-1
votes
0answers
21 views

Inductive effect on benzene ring [on hold]

I have read that : "Any charge on benzene ring gets stabilized or destabilized by Inductive effect only " If it is true then what is the reason behind this? Why don't we use Mesmeric and other ...
-1
votes
0answers
11 views

liquid and gaseous state at critical temperature [closed]

Assertion : At critical temperature liquid passes into gaseous state imperceptibly and continuously. Reason: The density of liquid and gases phase is equal at critical temperature (a) If both A &...
1
vote
1answer
60 views

Different shapes of fluorescence spectra in Raman

Note: I haven't owned any of these spectrometers. I'm asking so I can decide whether to buy 532nm or 785nm wavelength raman to probe molecular structure (especially solutions) and I'm concerned about ...
2
votes
1answer
71 views

Is Scandium considered a transition metal?

I have seen so many conflicting answers to this question in various places so I wanted to ask it again. IUPAC defines a transition metal as: "an element whose atom has a partially filled d sub-...
-3
votes
1answer
36 views

Why aerosol forms when you take a hot shower in a very cold day? [closed]

When temperature is about $\pu{17 ^\circ C}$ and I open the hot shower in maximum temperature (for a common electric shower) the air gets almost immediately full of droplets and this lasts the entire ...
0
votes
1answer
30 views

Negative hyperconjugation

Compare the acidity of the following compounds: $\ce{CF3OH}$ and $\ce{CCl3OH}$. My attempt: according to me $\ce{CCl3}$ group will show a stronger Negative hyperconjugation effect than $\ce{CF3}$, ...
-2
votes
1answer
59 views

Why does the addition of tetraethyl ammonium bromide reduce solution pH? [closed]

I am looking at a system that adds tetraethyl ammonium bromide to water. Over time, the concentration of tetraethyl ammonium bromide gradually increases, leading to a fall in the pH. I am trying to ...
1
vote
1answer
44 views

What is the meaning of the phase state label (cr,l) appearing in ATcT thermochemical data tables?

I was examining data associated with this post on the heat of solution of ammonium nitrate when I came upon the NIST ATcT data page which lists the heat of formation of $\ce{(NH4)NO3(cr,l)}$. In this ...
-3
votes
0answers
12 views

solid state ,crystallography of ionic compound that predict position of cation in respective voids [closed]

predicting position of cation in ionic crystals without the use of radius ratio rule .is this possible by brief explanation?solid state ,crystallography of ionic compound that predict position of ...
-1
votes
0answers
21 views

Simple multiple answer isotope question [closed]

I am studying for chemistry HL for the IB. For the following question, I do not know why A is the answer. Which statement about isotopes is correct? A Isotopes have the same molecular formula ...
2
votes
2answers
132 views

What is the safest way to hook up car battery jump cables and why? [closed]

I know that when both connecting and disconnecting battery jumper cables between two car batteries there is a prescribed safe way to do it. I can never remember the correct way because I can’t ...
0
votes
1answer
73 views

What makes ammonium nitrate soluble?

Ammonium nitrate is one of the classic examples of an endothermic dissolution. People will usually explain why it's soluble by stating that the spontaneous dissolution process of ammonium nitrate is ...
0
votes
1answer
115 views

Raman Spectrum of Water

This is the Raman spectrum of water. There is $\pu{1635 cm-1}$ Raman peak corresponding to $\ce{HOH}$ and $\pu{3410 cm-1}$ Raman peak corresponding to $\ce{OH}$. But why is there general nonzero ...
3
votes
1answer
102 views

Rechargeable Battery Based on Neutralization Reaction of Acid and Base [on hold]

The neutralization reaction, such as $\ce{HCl + NaOH → NaCl + H2O}$, generates heat, which is around $\pu{57.30 kJ/mol}$. Can we use this energy to design a battery? This idea occurs in my mind for a ...
0
votes
0answers
52 views

Linguistic origins of anion and cation [closed]

What are the linguistic origins of the terms “anion”, referring to an ion with a net negative electrical charge, and “cation”, referring to an ion with a net positive charge?
0
votes
1answer
37 views

Why is the binding angle of HOF lesser than that of H2O, despite the lone pairs and size of the flourine? [duplicate]

Why is the binding angle of HOF(101°) lesser than that of H2O?(104.5°) Since fluorine has unpaired electrons wouldn't it repel hydrogen more strongly than the corresponding hydrogen of H2O? Also, the ...
0
votes
0answers
49 views

Ce₂(SO₄)₃ solubility in water [duplicate]

I have mostly come across examples of solids whose solubility increases in liquids with an increase in temperature. However, there seem to be exceptions to generalized rule this such as the solubility ...
0
votes
0answers
13 views

Electron shells and subshells energies [duplicate]

According to what i learned in university, the energy of orbitals increases when the principal quantum number n increases. Also, in a given shell, s orbitals have lower energy than p orbitals which ...
-2
votes
2answers
54 views

does table salt dissolve in glycerin [closed]

Tell me, does table salt dissolve in glycerin? And is it possible to increase its solubility? I have vegetable glycerin with nicotine that I use for vape. So that nicotine would not be bitter, on ...
0
votes
1answer
54 views

How to convert 1,4 pentadiene to 1,3 pentadiene? [closed]

Are there any 'conjugating agents' to accomplish the above transformation? If not, then how to proceed?
-1
votes
2answers
32 views

Why does a NOx container get cold when NOx is released? and What is the relationship of the vapor pressure curve with the liquid-vapor dome?

The temperature at which $\ce{NO_x}$ is in equilibrium with its liquid and vapor phase at 1 atm is about –84 °C. Does that mean $\ce{NO_x}$ exists as a liquid at that temperature? What about it's ...
-2
votes
1answer
60 views

Molecular formula with CH without numbers [closed]

I was wondering if there exists a compound, the molecular formula for which includes CH but does not include any numbers. Like ...
0
votes
0answers
36 views

Andrew's experiment on liquefaction of gases [on hold]

Look at the region from C to B. Why is the pressure constant here while the volume of the gas is decreasing? Is it the phase where gas to liquid transition is going on? What I know In the region ...
-1
votes
1answer
25 views

Stability of π overlaps [closed]

Why are the 2p-2p π overlaps stronger than 3p-3p π overlaps? Also do stronger bonds have more negative potential energy? Please explain.
0
votes
1answer
35 views

Is the density of solute same as the density of solution? [on hold]

This problem came up while solving some problems on mass percentage and mole concept. Essentially, our teacher said that the $w/w\%$ and the $v/v\%$ for a given solution will be the same, because in ...
0
votes
0answers
28 views

However what is so acidic about CaO and basic(no pun intended) about SiO2 while calculating basicity of slag?

I have seen Basicity to be calculated as $\mathrm{B} = wt\%\:\ce{CaO}/wt\%\:\ce{SiO2}$ particularly in slag bascity/acidity calcuations. Now I do not think that $\ce{CaO}$ is the most basic oxide that ...
2
votes
0answers
38 views

What instrument is used to detect heavy metals? [closed]

If i have blood sample, organ tissue sample or food sample, what analytic technique is used in laboratory to detect the ppm levels of heavy metals? What electronic intrument they use?
0
votes
0answers
24 views

Resources for learning about protein structure determination by using cryo-EM from zero to hero [closed]

The title says overall. I am a third-year undergraduate student majoring in chemistry and took several biochemistry courses so perhaps the notion 'zero to hero' is a bit redundant, but I would like ...
0
votes
1answer
24 views

Applying Raoult's Law in volatile solids–liquid solutions

My textbook explains applying Raoult's Law for the two cases: liquid–liquid solutions, in which the vapour pressure of the solution is due to both the components non-volatile solids–liquid solutions, ...
1
vote
1answer
68 views

Why do we use coke instead of coal in order to reduce FeO as basic reaction in ironmaking process?

Why is coke used as a reducing agent to reduce FeO to produce iron instead of coal.I admit that coke is carbonaceous but what is it that compels us to use coke instead of the naturally available coal?
-2
votes
0answers
35 views

Ionic vs covalent behavior of sodium [closed]

The given chemical reaction: $$\ce{R-OH + NaBr + H_2 SO_4 \bond{->} R-Br + NaHSO_4 + H_2O}$$ I wanted to write the chemical mechanism of the chemical reaction, given above, but I'm facing a bit ...
-3
votes
1answer
49 views

Does LPG (cooking gas) react with water? [closed]

If cooking gas (or LPG) was exposed to some water in the gasline system, what would be the resultant by-product, and would this induce flame into the cylinder for explosion?
-3
votes
1answer
36 views

Comparison of stability of aromatic compounds [closed]

What is the basis of comparison between two aromatic compounds having different ring structures Like in propyl and heptyl rings
3
votes
4answers
126 views

Heisenberg's uncertainity principle(HUC)

I know the mathematical form of HUC and its statement i.e.It is impossible to determine simultaneously. , the exact position and momentum of an electron. i don't know why this ...

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