If your question is part of your high school or college/university homework, please use this tag. It signifies that instead of a direct answer, care should be taken to explaining the steps to the solution, preferably sticking to just giving helpful, conceptual hints. This tag may be applied to ...

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0
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0answers
20 views

Work out the equilibrium expression [on hold]

What would be the equilibrium expression for the following reaction. \[\ce{N2(g) + 3H2(g) <=> 2NH3(g)}\]
0
votes
0answers
29 views

Glycerol-->1,10 diaminodecane [on hold]

How can I get 1,10-diaminodecane (Synonym: 1,10-Decanediamine, Decamethylenediamine) in presence of Glycerol (substrate)? Linear Formula: $\ce{NH2(CH2)10NH2}$?
-1
votes
0answers
21 views

Define and explain the roles of protease, lipase and amylase in the human body [on hold]

Dedicate one slide per enzyme and include an image of the chemical, and the chemical that it operates on. Explain each enzyme’s general action, where it acts on its substrate, and where it is utilized ...
0
votes
0answers
39 views

How many hydrogen atoms are in a sample of NH3?

How many hydrogen atoms are contained in 8.66 moles of $\ce{NH3}$? The answer is given after the log has been taken, so the final answer is 25.19. What I have been doing is multiplying 8.66 by 6.02 ...
1
vote
1answer
28 views

Chemical formula and heat

In my Physical Science class, we are learning about chemical formulas and how to balance them. I balanced this equation: $\ce{Fe2O3 + Al -> Fe + Al2O3}$ One of the other students ...
0
votes
0answers
20 views

Boiling points of organics (AP Chemistry Question) [on hold]

I'm reviewing for the AP Exam and I came across this question: The answer would be B right?
1
vote
1answer
35 views

Ksp calculation of Cr(OH)2

At 25 °C, 10.24 mg of $\ce{Cr(OH)2}$ are dissolved in enough water to make 125 mL of solution. When equilibrium is established, the solution has a pH of 8.49. Estimate $K_\text{sp}$ for $\ce{Cr(OH)2}$ ...
-2
votes
0answers
22 views

Chemical Reaction Question [on hold]

The following reaction is performed in a lab: $\ce{3Na2SO4_{(aq)} + 2Al(NO3)3_{(aq)} ->Al2(SO4)3_{(s)} + 6NaNO3_{(aq)}}$ If 355 mL of 1.50 M aluminum nitrate is added to an excess of sodium ...
6
votes
1answer
26 views

Disproportionation of Pu species | Latimer's diagram

Why (according to provided answers) Pu(IV) disproportionates into adjacent species whilst Pu(V) does not in acid aqueous solution. I thought it is the other way - the more positive potential of ...
0
votes
0answers
31 views

double displacement with acid? [on hold]

sorry newbie chemistry questions bear with me please. In equations such as barium nitrate + hydrochloric acid -> barium chloride + nitric acid and ammonium chloride + HBr -> ammonium bromide + HCl ...
1
vote
1answer
29 views

how to depict answer from this graph

i am talking about the 65th question, in the below given uploaded photo, i.e. the first order decomposition curves as per the given reaction for every mole of A3 decomposed, there is a liberation ...
6
votes
0answers
29 views

Why isn't dry CaCl₂ used to dry HCl gas instead of concentrated sulfuric acid?

In our chemistry books (like Concise Chemistry), it is given that concentrated sulphuric acid is used to dry $\ce{HCl}$ gas. But, concentrated sulphuric acid is a strong oxidising agent so, why isn't ...
-5
votes
0answers
27 views

Finding Mass, Density, Volume

I'm a bit confused on how I'm supposed to figure this out when given such limited information. Perhaps one of you could enlighten me. The question is as follows. An 18 karat gold necklace is 75% ...
-4
votes
1answer
26 views

Stability constant for metal ion complex using reduction potential [on hold]

Determine the stability constant of the zinc tetramine complex from the equations: \begin{align} \ce{[Zn(NH3)4]^2+ + 2e &-> Zn + 4NH3} & E(\text{red}) &= -1.04~\mathrm{V}\\ ...
1
vote
2answers
38 views

How to determine the acidity or basicity of dissolved salts?

One kg of each substance below is dissolved in a bathtub full of water. Will it be acidic, basic, or neutral? $\ce{KNO2}$ $\ce{HF}$ $\ce{(CH3)3NHBr}$ $\ce{HO-CH2-CH2-O-CH2-Cl}$ ...
-2
votes
0answers
31 views

Help with homework problem please [on hold]

You have purified a new protein and find that it contains 0.198 percent Fe. Assuming that there are three atoms of iron per molecule of protein, what is the molar mass of the protein?
3
votes
1answer
25 views

How to choose a proper chromatography way to separate substrates?

I'm a freshman recently learned how to do TLC and column chromatography. I also know a little about other ways to separate things by chromatography, such as affinity chromatography, gel ...
0
votes
1answer
11 views

Determining enthalpy of neutralization and heat capacity of calorimeter by overlying with straight lines or “eye-o-metric method”

Below is a model example of how to interpret gathered data. Temperature on y-axis, time on x-axis. We are supposed to read (temperature change by neutralization) and (temperature change by resistive ...
-3
votes
0answers
34 views

Reaction between Acetylene and ammoniacal Silver Nitrate (Tollens' Reagent) [on hold]

So , the followings are known ,But from those I don't know how to deduce the answer.
-4
votes
0answers
25 views

Thermochemistry [on hold]

A sample consisting of 22.7 g of a nongaseous, unstable compound X is placed inside a metal cylinder with a radius of 8.00 cm, and a piston is carefully placed on the surface of the compound so that, ...
-3
votes
0answers
34 views

during a chemical reaction [on hold]

During a chemical reaction, equal moles of two diatomic molecules X and Y are allowed to react to form one gaseous compound XnYm. After the reaction is complete, it was observed that the density of ...
-2
votes
0answers
31 views

determine ∆H°f for X [on hold]

A combustion reaction is carried out by burning a sample of a compound X. The compound X, which is made of carbon and hydrogen, is allowed to completely react with oxygen gas. The products of the ...
1
vote
0answers
29 views

N,N dimethyl pyrrole cation conjugate base

In this compound what will be the structure of the conjugate base? I'm having a confusion from which position will the H leave and what will be the resulting structure!Please help. Because I was ...
2
votes
1answer
35 views

Air contain 20% O2 by volume. How many cc of air will be required for oxidation of 100cc of acetylene?

Air contain 20% $\ce{O2}$ by volume. How many cc of air will be required for oxidation of 100cc of acetylene? (a) 1064 cc(b) 212.8 cc(c) 500 cc (d) 1250 cc Answer: (d) My Solution: ...
0
votes
0answers
50 views

Calculate the final pressure, the composition of the mixture, and the partial pressures of the components?

A tank contains methane at 1000 psia and 140 F. Another tank of equal volume contains ethane at 500 psia and 140 F. The two tanks are connected, the gases are allowed to mix, and the temperature is ...
7
votes
0answers
33 views

Propose a chemical formula for the white solid that forms during the initial stages of the reaction of Sn with benzyl chloride

In my inorganic class, we carried out the synthesis of Chlorotribenzyltin, $\ce{SnCl(CH2C6H5)3}$. The synthesis begins with a reflux I'll describe below: In a hood, place 2.0 g (17 mmol) of 325 ...
-3
votes
0answers
38 views

Phase Changes of Dry Ice [on hold]

Use the phase diagram of carbon dioxide to explain (a) why solid carbon dioxide does not melt under regular classroom conditions and (b) why solid carbon dioxide sublimes under regular classroom ...
-3
votes
0answers
52 views

What volume of sulfur dioxide is produced at STP? [on hold]

5.00 L of $\ce{H2S}$ and 5.00 L of $\ce{O2}$ are allowed to react. Assume the reaction goes to the maximum extent possible. What volume of sulfur dioxide is produced at STP?
-2
votes
0answers
31 views

Cambridge A level Chemistry Questions [closed]

Can anyone explain to me these few questions? The density of ice is 1.00gcm-3. What is the volume of steam produced when 1.00cm3 of ice is heated to 323 degrees Celsius (596K) at a pressure ...
-1
votes
1answer
22 views

How do I calculate the new volume of an ideal gas upon temperature change [closed]

The problem asks a gas temperature of 14 degrees C, and a volume of 4.5L. If the Temperature is raised to 29 degrees C and the pressure is not changed, what is the new volume of the gas? The ...
0
votes
0answers
35 views

Stoichiometry chemistry question from a test [closed]

Element $\ce{X}$ can bond with chlorine to make $\ce{XCl2}$ (x-di chloride) and $\ce{XCl4}$ (x-tetra chloride). When 10 grams of $\ce{XCl2}$ reacts with an excess of $\ce{Cl2}$ it forms 12.55 grams ...
1
vote
0answers
21 views

Rate Kinetics(suggested mechanisms)-Chemistry [closed]

http://maxpapers.com/wp-content/uploads/2012/11/9701_w14_qp_41.pdf question 1C) The compound nitrosyl fluoride, NOF, can be formed by the following reaction. \[\ce{2NO(g) + F2(g) <=> ...
2
votes
1answer
67 views

Electrochemistry - Redox & Electroplating

I've stumbled across a problem that I need help on, it is mostly Electrochemistry and I will show my work. Line Notation Error: $$\ce{Fe~|~Fe^{+2}~||~Cl^{-},Cl2~|~Pt}$$ After that, I ...
6
votes
1answer
83 views

What is the hybridization of the carbonyl oxygen in a carboxylic acid?

My professor sent out a review guide. One of the questions on this guide is The carboxylic acid carbonyl oxygen is... A) $sp^2$ B) $sp^3$ C) H bond donor D) rapidly equilibrating between ...
1
vote
1answer
61 views

What happens when a soft drink containing citric acid is opened? [closed]

Citric acid is one component of some soft drinks. Suppose that a $2~\mathrm{L}$ solution is made from $150~\mathrm{mg}$ of citric acid, $\ce{C6H8O7}$. What products are produced when ...
3
votes
1answer
34 views

A question about osmolarity and osmotic pressure

You have discovered a new strain of bacteria called Tankeromyces subtilis that has a special outer membrane that is capable of withstanding high levels of osmotic pressure. These bacteria can ...
1
vote
1answer
40 views

How to calculate the pH of a buffer after dilution

You have a beaker containing 542 mL of a solution of 0.48M acetate buffer (pKa = 4.76) at pH 4.2. To this solution, you add 342 mL of pure water. What is the pH of the resulting solution? The ...
-3
votes
0answers
33 views

MO Theory: Ground state electron configuration and bond order [closed]

Please help... I don't understand how to complete this table. An explanation would be helpful. Thank you!
-3
votes
0answers
19 views

How to calculate the volume of sulfuric acid that contains a specific mass, neutralises sodium hydroxide or reacts with sodium carbonate? [closed]

What volume of $0.1~\mathrm{M}$ sulphuric acid Contains $4.9~\mathrm{g}$ of sulphuric acid Neutralises $25~\mathrm{cm^3}$ of $0.2~\mathrm{M}$ sodium hydroxide solution Reacts exactly with ...
1
vote
0answers
45 views

How is the titration affected? [closed]

during the titration a student pulls the pH electrode and rinses it off into a waste container before placing it. will this affect the measured equivalent mass? if so, how?
0
votes
0answers
33 views

Is it at equilibrium? [closed]

In a flask initially containing colorless molecules of $\ce{N2O4}$, the brown color characteristic of $\ce{NO2}$ appears and the color steadily becomes darker, is it at equilibrium?
2
votes
1answer
38 views

Help on a problem determining how much water would freeze in the solution

I came across a problem, I cannot solve in my 12th Grade Chemistry magazine .It goes like this A solution is prepared by adding 20 gram of Urea (Molecular Weight - 60 gram/mole) in 100 gram of ...
8
votes
1answer
831 views

What is the significance of 273.16 K?

Today, at my chemistry class, we were learning how to convert Celsius to Kelvin with exact values. I said we add 273.15 K to given Celsius but my colleague said we add 273.16 K. Yes, I did check on ...
6
votes
2answers
57 views

Zinc in acidic permanganate solution?

How can this be described by redox equation? My attempt: Half reaction as follows: Then overall reaction:
-4
votes
0answers
33 views

combustion reactions are exothermic, so why are reactions of metals with oxygen endothermic? [on hold]

All textbooks or websites I have visited say that combustion reactions are exothermic, yet I know that when a metal reacts with oxygen and forms a metal oxide it is an endothermic reaction. Isn't this ...
3
votes
1answer
42 views

Buffer calculation

Problem: A buffer was made by mixing 500 mL of 1 M (mol/L) acetic acid and 500 mL of 0.5 M calcium acetate. What are the resulting concentrations of acetic acid (henceforth called ...
1
vote
0answers
32 views

Ratio of rate of diffusion of two gases under constant temperature and pressure

I m consulting one of higher classes books to study chemistry. I had been studying Graham's Law and question related to rate of diffusion.I came across a question which says: calculate the ratio ...
-3
votes
1answer
29 views

Need to calculate total price on the market in grams instead of Litres [closed]

In my assignment, I am given the table of all elements for which have to calculate the price on the market. For example, ...
-3
votes
0answers
16 views

30.0 mL of 0.10 M NaOH neutralized 25.0 mL hydrochloric acid. Determine the concentration of the acid [closed]

30.0mL of 0.10 M NaOH neutralized 25.0mL of Hydrochloric acid. Determine the concentration of the acid.
1
vote
1answer
24 views

How do you determine whether or not a acid will be destroyed upon the addition dilute bases and acids?

So I have a liter of buffer consisting of .1 M $\ce{HF}$ and 0.05 M $\ce{NaF}$. I'm given three solutions to determine what would essentially destroy the buffer: (a) 0.050 mol of $\ce{HCl}$ (b) ...