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Chemistry: Post your doubts here!
The 'most probable energies' at a specific temperatures are the respective peaks When temperature increases, the peak is lowered, thus less particles will have the most probable energy -
Chemistry: Post your doubts here!
50 cm^3 of CH4 will react with 100 cm^3 of oxygen to produce 50 cm^3 of CO2 and water Immediately after the reaction, we will have mixture of 50 cm^3 of CO2 and 50 cm^3 of O2 (excess unreacted) The acidic CO2 would be absorbed by the KOH (alkali) leaving only 50 cm^3 of O2 in the tube -
Chemistry: Post your doubts here!
I don't have the context of the full question. But in both equations, the ratio of Ba(NO3)2 and N2 happens to be 1:1. Therefore, it's a coincidence that the answers ended up to be the same. -
Chemistry: Post your doubts here!
2-bromo-2-methylbutane is a tertiary halogenoalkane and will undergo sN1 'unimolecular' via carbocation reactions. The C-Br bond will be broken heterolytically and a carbocation ion will be formed. The carbocation would then be attacked by the nucleophile (OH-) -
Chemistry: Post your doubts here!
For statement 3, we need to be aware that ethene is a gas at room conditions, and will not be contained in the distillation flask for the reaction to take place. -
Chemistry: Post your doubts here!
"forms orange crystals on reaction with 2,4-dinitrophenylhydrazine" means that the products contain aldehydes and/or ketone functional groups A. Will produce CH3COOH , CO2 , H2O , no reaction with 2,4-DNPH B. Will remain as CH3COCH2CH3 (ketone) which reacts with 2,4-DNPH to form orange... -
Chemistry: Post your doubts here!
3.40 g of the compound was dissolved in 250 cm^3 , and only 25 cm^3 of the 250cm^3 was used in the titration. So when we need to find the original amount in 250 cm^3 , we need to multiply by a factor of 10 -
Chemistry MCQ thread...
Note that ammonium chloride does not appear in the Kc expression as it is a SOLID. -
Chemistry: Post your doubts here!
We should look beyond the immediate neighbors, 6 and 7 aren't exactly the same The symmetry is at carbon 7, that is why 6 is the same as 6a and 5 is the same as 5a, but 7 is not the same as any of them A simplified view of the molecule is shown before to hopefully explain the symmetry... -
Chemistry: Post your doubts here!
Use a table to keep track of the moles of CH3COOH removed by the NaOH , and thus the amount of salt formed. You should be able to find the respective concentrations easily after that -
Chemistry: Post your doubts here!
Yes, that's a valid concern. That's when we would need to search within the collection of equations (a non-metal tetrachloride) which are familiar to us and find a close match I've originally typed in SiCl4 (within the syllabus) instead of SCl4 (outside the syllabus). I've just checked the... -
Chemistry: Post your doubts here!
Apologies, I should have typed S (sulfur) instead of Si (silicon) I'll amend the post -
Chemistry: Post your doubts here!
When the element used in a question is unfamiliar, we try to use known equations as a comparison. We know that SCl4 + 2H2O --> SO2 + 4HCl, since Te and S are in the same group, we can expect TeCl4 to follow the reaction Edit: Typed Si instead of S -
Chemistry: Post your doubts here!
Do include the year of the paper and answer next time for easier reference -
Chemistry: Post your doubts here!
This is a good explanation. I would like to add to the last sentence. "Anything that successfully dissolves, you can be sure it's an exothermic process." There are some substances that dissolve and are endothermic (e.g. dissolving ammonium chlorides), a spontaneous reaction does not only... -
Chemistry: Post your doubts here!
You can check my youtube playlist, there are a few years available. -
Chemistry: Post your doubts here!
I can't see the right side of the question, should I assume that the charge is -3? Sodium metal will react with carboxyl groups COOH and hydroxyl OH groups to form COO- and O-. So if we have a total of 3 such groups, it will form a -3 charge Sodium hydroxide will react with COOH and not OH -
Chemistry: Post your doubts here!
Increasing the pressure also increases the concentration of the gaseous reactants, therefore the rate of backward is also expected to increase. However, the equilibrium will still shift to the right as the increase in the rate of the forward reaction is more than the increase in the rate of... -
Chemistry: Post your doubts here!
Holmes For papers from 2013 and 2012, I have created some videos to explain the MCQs. You can search through the playlists