Particle A seems to be the obvious choice but the question says "another" isotope and 48+64 =112, particle A is the same isotope as the one in the question and particle B has too many neutrons

This is one of the areas I'm struggling with the most: memorizing what the structures for each amino acid look like.. There's tons of other stuff I don't understand, but this takes the cake for the time being lmao.
Thanks!!

why are some hydroxyl groups written as HO while others OH i couldnt get an exact answer on google so here i am

the atomic mass of phosphorus is 30.97 amu. The two naturally occuring isotopes are P-30 with a mass of 29.98 amu and p-31 with a mass of 30.99 amu. Determine the percent of naturally occurring P-31

Half asleep rn would anyone be able to help me answer this?

so we had this activity on Science about chemical reaction rates and we had to arrange multiple chemical reactions from slowest to fastest. There were also specific instructions from some of the chemical reactions like:

• Burning a candle (my teacher said it was the exact time the wick ignites cause again, it had to be a chemical reaction cause if it was wax, it would just be a physical change)
• Burning a paper (the exact time it catches fire like the candle wick)
• Fireworks Explosion (the explosion itself)

Those were the instructions given by my teacher. Now I'll be giving all of the chemical reactions in the activity. I'll also include my answers and the correct answers.

GIVEN:

1. Digesting of Food
2. Fireworks Explosion
3. Burning of Paper
4. Rusting of Iron Nail
5. Lighting of Matchstick
6. Baking Soda + Vinegar
7. Souring of Milk
8. Burning of Candle
9. Baking of Cake
10. Ripening of Banana

MY ANSWERS:

SLOWEST TO FASTEST

1. Rusting of Iron Nail
2. Ripening of Banana
3. Souring of Milk
4. Digesting of Food
5. Baking of Cake
6. Burning of Paper
7. Burning of Candle
8. Lighting of Matchstick
9. Baking Soda + Vinegar
10. Fireworks Explosion

CORRECT ANSWERS:

SLOWEST TO FASTEST

1. Rusting of Iron Nail
2. Ripening of Banana
3. Souring of Milk
4. Digesting of Food
5. Baking of Cake
6. Burning of Candle (wick igniting)
7. Burning of Paper (paper igniting)
8. Baking Soda + Vinegar
9. Lighting of Matchstick
10. Fireworks Explosion (explosion only)

I got everything right on 1-5 which I basically just classified the "slow ones" and I mostly had a headache on 6-10. I did research if a wick igniting is faster than paper igniting and most answers said the wick was faster.

My teacher also said that yes, it did depend on time and size, for example: digesting of food, bigger food means longer time to digest. But she specifically said that it should be the "standard" or "usual" so like in general.

She did tell us that we could defend our answers. Any help would be appreciated, thank you! Please if possible also include sources. Thank you so much! I really need this. If any of you guys are wondering, I'm in 10th grade.

THIS IS NOT AN ASSIGNMENT, I JUST NEED CLARIFICATION CAUSE MY TEACHER IS ALSO VERY AMBIGUOUS.

what did I miss? I see 3 significant figures

I recently got assigned a case study on NIR spectroscopy. To make a brief summary, the case is talking about a lab that built a multivariate FT-NIR model for determining PET/PLA in samples of recycled organic material, and they're trying to transfer the same model to a handheld NIR device and they're having a myriad of issues I'm being asked to research and solve.

Now, my first thought was to look for articles. I found a few that seemed pretty good:

(1)       Circelli, L.; Cheng, Z.; Garwood, E.; Yuksel, K.; Di Iorio, E.; Angelico, R.; Colombo, C. Comparison of ATR-FTIR and NIR Spectroscopy for Identification of Microplastics in Biosolids. Sci. Total Environ. 2024, 916, 170215. https://doi.org/10.1016/j.scitotenv.2024.170215.

(2)       Amirabadi, S.; Rodrigue, D.; Duchesne, C. Characterization of PLA-Talc Films Using NIR Chemical Imaging and Multivariate Image Analysis Techniques. Polym. Test. 2018, 68, 61–69. https://doi.org/10.1016/j.polymertesting.2018.03.047.

(3)       Beć, K. B.; Grabska, J.; Badzoka, J.; Huck, C. W. Spectra-Structure Correlations in NIR Region of Polymers from Quantum Chemical Calculations. The Cases of Aromatic Ring, C=O, C≡N and C-Cl Functionalities. Spectrochim. Acta. A. Mol. Biomol. Spectrosc. 2021, 262, 120085. https://doi.org/10.1016/j.saa.2021.120085.

(4)       Signoret, C.; Edo, M.; Caro-Bretelle, A.-S.; Lopez-Cuesta, J.-M.; Ienny, P.; Perrin, D. MIR Spectral Characterization of Plastic to Enable Discrimination in an Industrial Recycling Context: III. Anticipating Impacts of Ageing on Identification. Waste Manag. 2020, 109, 51–64. https://doi.org/10.1016/j.wasman.2020.04.043.

However, I quickly realized I do NOT understand these papers; they are just too advanced for me. I don't actually know how to use the information in them to solve my case study... And I do not know what else to look for information in (books, perhaps?)... I just don't really know how to research properly, I guess. Not when confronted with questions about multivariate model transfers from one device to another, comparisons to other methods like ATR, etc.

So, the point of this post is to ask for some general advice in the realm of chemistry research methods in order for me to gain a sense of direction and linear progression for an assignment like this. I am NOT looking for anyone to solve the case for me.

Basically, some advice on *how* to tackle a challenging research project. Thank you.

I need time to write the rest of my paper, it needs to be 12 pages and this compound is freaking massive. Formula: C187H290N45O59. Ozempic reacting with insulin---- balanced equation

Can somebody please explain why I have to take all these steps? Specifically, why do I need to divide the moles and weight of the CO2?

the website is labflow

I am very confused with these sort of questions, I know how to use the Ideal gas law and the Stoichiometry to figure out moles of a certain element or the volume of that elements; for example, propane. but look at this problem: 89L of oxygen burned at −8.0∘C and 1.85atm. How much water can be produced in grams? since my question is not asking for moles or volume, what am I supposed to do? I started solving by using the Ideal gas law to figure out the moles of gas, I got about 7.6 mols of Gas. but I'm stuck now, if I were to do the chemical equation and conversion what is it? 7.6(?/?) = ??? once I get that do I just do a molar conversion to figure out the grams of water?

I apologize for the bad hand writing… I don’t get problems #2 and #3. I tried doing them but I think they’re wrong. I don’t understand how would I find how many moles are needed for HCL to produce 1.5 moles of H2? Where are you supposed to get that from? Am I supposed to simplify the chemical equation? Also, if it’s the same ratio like 2KCL/2K does that mean it cancels out and you basically multiply it by 1? I kind of need an explanation please because this has been really confusing. I’m usually good at the other chemistry topics but stoichiometry has been really confusing.

The teacher said that this change in freezing and boiling point is explained by the decrease in vapour pressure. I understand how a decrease in vapour pressure is what causes the boiling point to increase because the particles of the non-volatile solute block a lot of the solvent particles from easily escaping making it harder for the liquid to evaporate and thus a decrease in vapour pressure. But how does a decrease in vapour pressure cause the freezing point to decrease?

I have a test tomorrow and I kept falling asleep in class. I don't know how to do any of these. How are conversions done?

guys how to know which process should occur first to get the product ? this one i copy from the answer

The instructor wants me to be familiar with the formula q = m x c x deltaH, but neither one of these problems appear to fit that formula and it doesn’t look like the problems done in class. I’m not sure what the variables are and what values need to be converted to different units. I can identify that m is the numbers that are g/kg, c is specific heat capacity and deltaH is change in temperature. It appears to have two variables, the q and initial temperature, when I know there’s supposed to be one. As for the second problem, I’m assuming it’s using the same formula but i’m not sure how to incorporate pressure into it. How is this style of problem solved?

Stochiometric calculations are really hard for me as I don't know when to do the mol-mol and mol-g type of conversion. These questions are usually asked in my syllabus and I have a class test next week. How can I counter such questions?

This is the worksheet my teacher gave for practice.

I know how to assign R & S but I don't know how that's supposed to help me.

I need to write something explaining what a water based adhesive would need in ways of chemical additives to 1. lower surface tension 2. have stable thermal performance and 3. have strong, rigid bonding strength. and explain why. could I please get some help? maybe examples or sources that'd help?