Questions tagged [chemical-formula]

For questions related to molecular formula, empirical formula, formula unit, representing the chemical proportions of atoms that constitute a particular chemical compound, molecule, ion, complex, crystal, etc. using chemical element symbols, numbers, and other symbols. NOT related to 'notation', 'composition', 'structure' or 'nomenclature'.

Filter by
Sorted by
Tagged with
-2 votes
0 answers
22 views

Chemical formula on non-stoichiometric compounds

I have a question regarding the compound, Cs$_{0.1}$FA$_{0.9}$PbI$_{2.865}$Br$_{0.135}$, which I noted as a non-stoichiometric compound due to the fractional subscripts. (I am not a chemist, so ...
3 votes
1 answer
257 views

Empirical formula and rounding

I am very confused with the procedure to find the empirical formula. In the part where we have to multiply by subscripts to make them integers, are there clear rules? For example, if I have the ...
  • 139
-2 votes
0 answers
22 views

Replacement solvent for Ethyl lactate [closed]

Is there a replacement solvent for Ethyl lactate used in a formulation of an urethane adhesive for bonding urethane to metal in a molding process
-2 votes
0 answers
12 views

Chemicals in a Rubber Adhesive - QC 136-1, Pegasol 2530, Santiczer 160, Agerite White, Altax and Cerechlor 70L [closed]

I have a recipe for a rubber adhesive and am trying to understand some of the ingredients. Some of my research indicated what these are but looking for replacement products? They are: QC 136-1 - Don't ...
-1 votes
2 answers
55 views

Number of neutrons in a chemical question?

Consider the equation $\ce{H2 + H2+ -> H + H3+}$ What is the atomic structure of the $H_3^+$ ion? I understand that the H$_3^+$ ion contains 3 protons and 2 electrons. However, how many neutrons ...
  • 9
0 votes
1 answer
73 views

How to write formula for potassium hydrogenpyrophosphite?

I know that pyrophosphite by itself is $\ce {({P_2}{O_5})^{4-}}$. My question is about the hydrogen part- how to know how many hydrogens to add? The answer key for this question says the compound is $\...
  • 317
0 votes
3 answers
123 views

Is there a concise way to calculate pH of a solution after being diluted with water?

I do not have a chemistry degree or even much knowledge in the subject at all. I'm actually an auto detailer and this is why I have an interest in pH levels. All of our chemicals obviously have pH ...
-1 votes
1 answer
44 views

Resorcinol turned brown [closed]

I stored resorcinol in a transparent plastic container with an airtight lid. There was some air captured inside the container too. After some days, it turned brown. please tell what happened to it?
  • 1
1 vote
0 answers
48 views

How to get the total number of numbered positions in a molecule/compound

I'm working on a metabolite database where "labeled" compounds can contain isotopically labeled atoms in specific positions. When a new labeled compound is entered into the database, we'd ...
  • 119
0 votes
0 answers
41 views

How do I calculate the empirical formula when ash is present in the percentage composition?

I am trying to calculate a chemical formula. How do I calculate the empirical formula when ash is present in the percentage composition? Example- C- 47.7% H- 7.2% N- 1.8% S- 0.9% O- 38.0% Ash- 4.4% ...
-2 votes
2 answers
1k views

Reaction between NaCl and NaHCO3 [closed]

Does NaHCO3 (aq) react with NaCl(aq)? I don't think they should undergo any reaction but in the online database it is showing that they react to form Na2CO3 and HCl. Is it correct?
0 votes
1 answer
426 views

Why is Pb3O4 called lead(II,IV) oxide?

We know that iron(II,III) oxide has the formula $\ce{Fe3O4}$ which is a combination of iron(II) oxide and iron(III) oxide with formulas $\ce{FeO}$ and $\ce{Fe2O3}$ respectively. So why isn't this the ...
0 votes
0 answers
29 views

How can the multiplicative number (n) of a chemical series like polyethylene glycol (PEG) be a non-integer?

https://en.m.wikipedia.org/wiki/PEG_400 Down at chemical or molecular formula, it says: C_2n H_4n+2 O_n+1, like for all polyethylene glycols (PEG)s, but then says n=8.2 to 9.1.... Huh?
  • 1,759
0 votes
1 answer
75 views

How to find the empirical formula from mass percentages of oxides [closed]

Say you've given an element X and it makes two oxides. The first oxide is $X_\mathrm{4}O_\mathrm{6}$ and the mass percentage of oxygen is 43.7%. In the second oxide, the mass percentage of X is 43.7%. ...
4 votes
2 answers
205 views

Are there examples of molecular formulas with nested groups?

Sometimes a molecular formula is written using groups, for instance $\ce{Al2(SO4)3}$. Are there examples of formulas with nested groups, such as $\ce{ABC[MNO2(XYZ)4]3}$ or is this avoided?
  • 151
1 vote
1 answer
89 views

Using the mole ratio to figure out the molecular formula [closed]

It takes $\pu{8.0 cm^3}$ of aqueous sodium phosphate to fully react with $\pu{12.0 cm^3}$ of an aqueous solution of the nitrate of metal $\ce{T}$. If both solutions have a concentration of $\pu{1 mol ...
  • 196
1 vote
2 answers
535 views

Combustion analysis of hydrocarbon

Combustion analysis of a hydrocarbon produced 33.01 g CO2 and 4.84 g H2O. I was asked to find the empirical formula of the hydrocarbon. I used these molar mass values for my calculations: C - 12.0107 ...
7 votes
2 answers
834 views

What is the chemical composition of Ferrous Ferrocyanide?

To this day, iron-cyanide complexes confuses me. So, I want to settle this once and for all. After scavenging the internet, I gathered the following result: $$ \ce{Ferr} \color{blue}{\ce{ous}}~\ce{...
7 votes
1 answer
226 views

How to understand the chemical formula of Prussian blue complex w.r.t its crystal structure?

Note: Just to be clear, I do not refer to "complex molecules" (i.e. "complex" as "complicated"), but to actual complexes. I am trying to understand the structure of ...
  • 263
4 votes
1 answer
967 views

How can I mix methylene chloride, methanol and hydrofluric acid to make a paint stripper?

HF paint stripper on data sheets lists Methylene chloride 70>85% Methanol 10>25% Hydrofluric acid. 5% Previously I have found the chemical splits. Is there a particular method to ...
0 votes
1 answer
124 views

On basic mercury salts

$\ce{HgCO3.3HgO}$ and $\ce{HgO.Hg(NH2)Cl}$ are called basic mercury carbonate and basic mercury amidochloride, respectively. I found this thread on the former; I've only seen the latter as the product ...
  • 1,116
2 votes
0 answers
113 views

What does fractional notation represent in molecular formulas such as SiO4/2 or H2SiO2/2?

I'm going through some papers about HSQ (hydrogen silsesquioxane) and keep seeing this fractional notation being used: HSiO3/2 , SiO4/2 , H2SiO2/2 , H3SiO1/2. Example paper. I understand that the ...
5 votes
2 answers
496 views

What is the maximum number of water molecules that has been recorded till date to present as water of crystallization in a compound?

Context: I was casually looking through some old questions when I found this question. The OP wanted a compound that has all the hydrates ranging from monohydrate to decahydrate. I found chromium(III) ...
1 vote
1 answer
132 views

Finding formula of reduced scandium oxide using its mass and mass of obtained metal

An oxide of scandium, with a mass of $\pu{1.423 g},$ is chemically reduced with $\ce{H2}$ to give $\ce{H2O}$ and $\pu{0.929 g}$ of $\ce{Sc}$ metal. What is the formula of scandium oxide? How much ...
  • 99
1 vote
0 answers
15 views

What are the additional chemicals required to make polyurethane foam more viscoelastic? [closed]

I am currently experimenting with polyurethane forms for a science and research project I am working on. I need to make the polyurethane foam more viscoelastic, almost like memory foam. I am unable to ...
6 votes
1 answer
96 views

Are atom coordinates in molfile necessary to produce a valid InChI identifier

I took this molfile of benzoic acid: ...
0 votes
1 answer
40 views

How to interpret this formula about hydrogen bond energy

I want to evaluate some chemistry related formulas, which I don't understand. In proteins, hydrogen bonding often occurs between the oxo group = O oxygen of one amino acid and the α-amino group (N − H)...
-4 votes
1 answer
961 views

What's the chemical reaction between coffee and sodium bicarbonate? [closed]

Every morning I put sodium bicarbonate into my coffee and I was wondering what chemical reaction this produces and what are the chemicals produced at the end. I cannot find an answer to this question ...
1 vote
1 answer
682 views

Si(OH)4 vs. H4SiO4 vs. SiO2.2H2O

Can someone please explain to me what is the differences between $\ce{Si(OH)4}$, $\ce{H4SiO4}$, and $\ce{SiO2.2H2O}$? I am currently studying sandstone acidizing geochemical models and this question ...
-1 votes
1 answer
172 views

How is Potassium present in Potato (form) and where does it come from originally? [closed]

I was going through the concept of Boiling to reduce the potassium in Potatoes, which means $\ce{potato + water +heat -> potassium + X}$. $\ce{X}$ is potato with reduced potassium. I am more ...
  • 107
0 votes
0 answers
210 views

Chemical reaction of bronze tarnishing

Can anyone explain to me the chemical process of bronze tarnishing? According to Wikipedia: Bronzes are typically ductile alloys, considerably less brittle than cast iron. Typically bronze oxidizes ...
  • 109
1 vote
0 answers
30 views

Determining the number of triphenylphosphine ligands in nickel(II) complex

A complex is synthesised by combining hydrated solutions of $\ce{NiCl2}$ $(\pu{0.6 g})$ with $\pu{1.35 g}$ triphenylphosphine $(\ce{PPh3}).$ After cooling the product precipitates as a solid with ...
user avatar
1 vote
1 answer
957 views

What's the difference between Zinc Ascorbate and Zinc Gluconate?

I've been looking at a dental product for pets, called MAXI/GUARD Oral Cleansing Gel and it states it uses zinc ascorbate/taurine, however in the ingredients I found elsewhere it instead lists zinc ...
  • 39
-5 votes
1 answer
2k views

What is the chemical formula of ghee? [closed]

What is the chemical formula of ghee (Indian butter)? Also, name the elements present and state the number of their atoms.
2 votes
0 answers
118 views

How to use NMR readings to determine the molecular structure of a compound? [closed]

A question in my exam came as follows: How is NMR used in the determination of structure of organic compounds? I have studied NMR spectroscopy and I know how to determine values using an NMR ...
1 vote
0 answers
49 views

Kinetics of Decomposition of Hydrogen Peroxide [duplicate]

Consider the decomposition of Hydrogen Peroxide: $$\ce{H2O2 -> H2O + 1/2O2}$$ The rate law for this reaction is : $$\text{Rate} = k[\ce{H2O2}]$$ Further $$\text{Rate} = -\frac{\mathrm d[\ce{H2O2}]}...
0 votes
0 answers
44 views

What is one formula unit? [duplicate]

I am really sorry if this is a beginner question but please still help me. In this website, which explains balancing chemical equations mentioned the word formula unit here: $\ce{3Ca(NO3)2}$ (just ...
-2 votes
1 answer
197 views

Sucrose skeletal formula - missing Carbon and Hydrogen [duplicate]

I was reading the Wikipedia article about Sucrose, when I noticed that the skeletal formula was missing some $\ce{C}$ and $\ce{H}$ atoms. The chemical formula being $\ce{C12H22O11}$, I counted the $11$...
-3 votes
1 answer
170 views

Lewis structures and chemical-compound formulas [closed]

In the Lewis structures listed below, M and X represent various elements in the third period of the periodic table. Write the formula of each compound using the chemical symbols of each element: a. b. ...
0 votes
1 answer
738 views

What is the chemical formula for the synthesis of Hydroxyapatite (Ca10(PO4)6(OH)2)?

This might be a basic question but I am a little confused. I have some lecture notes that says calcium phosphate ($\ce{Ca3(PO4)2}$) reacts with calcium hydroxide ($\ce{Ca(OH)2}$) to form ...
0 votes
1 answer
63 views

Separating Silica from silicates [closed]

Does anyone know how one could extract Silica $\ce{SiO2}$ from a one or more of the following compounds in either ground or powder forms? Plagioclase: $\ce{Ca2Al2Si2O8}$ Pyroxene: $\ce{(Ca,Mg,Fe)...
-3 votes
1 answer
61 views

I am having trouble with this question on net ionic equation [closed]

Convert into molecular equation: The reaction between potassium dichromate, ferrous sulphate and sulphuric acid:- Cr2O7^2- + 14H^+ + 6Fe^2+ ---> 6Fe^3+ + 2 Cr^3+...
1 vote
0 answers
256 views

The equation representing the dissolution of cycasin [closed]

Is the following equation correct? $$\ce{{C_8H_{16}N_2O_7}_{(s)} + H2O_{(l)} <=> {C_8H_{16}N_2O_7}_{(aq)}}$$
  • 78
1 vote
0 answers
36 views

What is the materials science behind thermal diffusion in multispectral camouflage?

I've been interested in infrared and near-infrared camouflage (called multispectral camouflage) for a couple of days now, and I've found a video or two of certain companies that have created fabrics ...
-1 votes
3 answers
3k views

What's the effect of Pressure change in Chemical Equilibrium if any reactant or product is Solid or Liquid?

I am studying La-Chatelier's Principle of Chemical Equilibrium. I got a problem of Pressure change in Chemical Equilibrium. I know that Pressure change If a reversible reaction is in equilibrium ...
  • 1
2 votes
1 answer
556 views

Empirical and molecular formula

I was doing a homework assignment and I got the question wrong because I was supposed to multiply the empirical formula of $\ce{C6H10S2O}$ by 3 to get the molecular formula. I put $\ce{(C6H10S2O3)3}...
  • 31
3 votes
1 answer
1k views

Chemical formula of a compound crystallized in a cubic lattice

Question In a cubic lattice of $\ce{XYZ},$ $\ce{X}$ atoms are present at all corners except one corner which is occupied by $\ce{Y}$ atoms. $\ce{Z}$ atoms are present at face centres. What is the ...
3 votes
1 answer
4k views

Ratio of copper(II) ions to EDTA?

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 atom, but is that what they are asking for with "...
  • 424
3 votes
1 answer
305 views

Can two positive ions be next to each other in a formula?

Let's say I want to find the oxidation numbers of the atoms in a chemical formula. For example: In $\ce{H3AsO3}$, Oxygen has a $-2$ charge. They're $3$ of them, so its $-6$ Hydrogen has a $+1$ ...
  • 312