53
votes
Accepted
Why isn't ethane used for cooking?
Probably the biggest drivers behind using methane as a fuel is that it is abundant in natural gas and is (currently) mostly useless as a chemical feedstock.
Ethane makes up a few percent of natural ...
- 12.7k
51
votes
Why do we call O2 oxygen?
I think what you may find most helpful is to know a bit of the history of element discovery and atomic theory.
The first pure substance containing only the element oxygen to be isolated was dioxygen (...
- 27.4k
39
votes
Why isn't ethane used for cooking?
In both cases, there appears to be a confusion of terminology between common and technical uses.
We commonly use methane and propane for cooking (and home heating), but not ethane. I would expect ...
- 17k
39
votes
Accepted
Does water have a chemical name?
TL;DR IUPAC hasn’t made up their mind, but plain old water appears to be an appropriate name. However, chemical derivatives of water may not be named using water.
In Nomenclature of Organic Chemistry:...
- 69.6k
34
votes
Accepted
Is an isobar the same as an isotope?
Not quite, an isotope has same number of protons ($ A- N = Z = \mathrm{constant}$), but a different number of neutrons ($\mathrm N$ varies; e.g. $\ce{^3_\color{red}{1}H}$ and $\ce{^2_\color{red}{1}H}$,...
- 12.1k
33
votes
What is a word for "atom or molecule"?
The classic catch-all term is molecular entity, often abbreviated to just entity. There's a Wikipedia page for it, which references the IUPAC Gold Book entry. Quoting from the latter:
Any ...
- 27.4k
32
votes
Accepted
Does the term 'Cation' always refer to a positively charged particle?
Yes, cations always have a positive charge and anions always have a negative one.
The difficulty is that the term cathode and anode do not always correspond to the same pole. The cathode is that pole ...
- 66k
29
votes
Accepted
Why is ammonium a weak acid if ammonia is a weak base?
First, let’s get the definition of weak and strong acids or bases out of the way. The way I learnt it (and the way everybody seems to be using it) is:
$\displaystyle \mathrm{p}K_\mathrm{a} < 0$ ...
- 66k
27
votes
Accepted
How 'heavy' should an element be, to be a "Heavy Metal"?
There is no true, accepted definition of heavy metal. I was taught to apply the option a metal that has density equal to or over $5.0\ \mathrm{g/cm^3}$.
Other variants include a different density ...
- 6,922
26
votes
Accepted
Is there a difference between equilibrium and steady state?
Yes, equilibrium and steady-state are distinct concepts.
A reaction is at equilibrium if reactants and products are both present, the forward and reverse rates are equal and the concentrations don't ...
- 35.4k
25
votes
Accepted
A drop of water in a tin of sugar: Which one's the solvent, the sugar or the water?
You could imagine stirring the sugar enough for the water molecules to be uniformly distributed throughout - it would then be homogeneous.
However, even then, to refer to the mixture as a solution ...
- 822
23
votes
What is difference between H⁺ and proton?
There is no chemical difference, only a psychological one: how do you think about it. They are both the same thing, but many people associate $\ce{H+}$ ions with chemical reactions and protons with ...
- 7,254
23
votes
Accepted
Why "monoxide" but not "diodine"?
Both "monooxide" and "monoxide" are used in the literature, yet "monoxide" is being used more often (Google Books Ngram Viewer).
Although this is an accepted elision, it ...
- 36.9k
22
votes
Accepted
Is beryllium an alkaline earth metal?
There is some disagreement in usage among authors, but IUPAC standard nomenclature approves calling beryllium an alkaline earth metal, as explained on page 51 of IUPAC's last Red Book.
In fact, all ...
22
votes
Accepted
Etymology of alanine
In the original German paper [1] Adolf Strecker used Aldehyd-Ammoniak or aldehyde-ammonia as a precursor, that's where the name derives from:
Vor einigen Jahren habe ich gezeigt, daſs Aldehyd-...
- 36.9k
21
votes
"Estrontium" on poster
"Estrontium" is not used as an element name in any language. It appears that the error traces to a single user by the name of Alejo Miranda (listed as from Ecuador) who has posted a large collection ...
- 9,977
20
votes
Accepted
Why is boric acid written as B(OH)3 and not H3BO3?
This is mostly because boric acid is commonly believed to have different acidity mechanism. While common acids generally dissociates
$\ce{HNO3 <=> H+ + NO3-}$
boric acid is commonly believed ...
- 21.1k
20
votes
What does “to the left” mean?
Yes, "to the left" refers to the left side of an equilibrium expression.
Traditionally, the autoionization of water is written as
$$\ce{2H2O <=> H3O+ + OH-}$$
When we talk about equilibrium ...
- 3,343
20
votes
Accepted
Can a solvent be a solid?
When most people think of the term solvent, a liquid medium comes to mind; however, in the technical sense of the definition, this does not have to be the case. Here is the definition of a solution ...
- 1,837
20
votes
Accepted
What is a Herzberg?
Herzberg filtration speed: The time taken to filter $\pu{100 mL}$ water at $\pu{20 ^\circ C}$ through a filter area of $\pu{10 cm2}$ at a constant pressure of $\pu{5 cm}$ water column (Thomas ...
19
votes
Is an acid a salt or not?
It is a semantics question with an open ended discussion. If you recall the old problem "How many angels can dance on a pinhead? Medieval problem, this issue here is similar.
Basically in chemistry, ...
- 36.6k
19
votes
Accepted
What is the intuition behind 'mol' as a unit 'symbol'
The symbol mol is due to Ostwald who was a very influential and respected physical chemist more than a century ago. In German, "mole" is "Mol". It is a shortform of Molekül.
I ...
- 36.6k
18
votes
Why is the Vitamin B complex, a "complex"?
It is essentially exactly what your teacher says: the term vitamin B complex is used because the structures assigned a name ‘vitamin Bx’ don’t really have anything in common although they are all ...
- 66k
18
votes
Why do most drugs (eg: oxycodone) have seemingly arbitrary names?
The reason why the generic name of most drugs have seemingly little semblance to their chemistry is in the interests of practicality; a doctor would find it easier to write sildenafil (generic name) ...
- 18.3k
17
votes
Why is an ionic bond a chemical and not a physical bond?
Short version:
We don't call bonds "physical", there are chemical bonds and other types of interactions between particles. The chemical bonds are classified this way because they make up molecules, ...
- 1,492
17
votes
Does the term 'Cation' always refer to a positively charged particle?
From what I was taught in Middle-school, cations are those ions that
move towards the cathode, likewise anions are those ions which move
towards the anode.
Nope, the definitions are as follows (from ...
- 18.7k
17
votes
A drop of water in a tin of sugar: Which one's the solvent, the sugar or the water?
Both answers are right. In the IUPAC Gold Book it states
A liquid or solid phase containing more than one substance, when for
convenience one (or more) substance, which is called the solvent, is
...
17
votes
Accepted
What is the scientific term to describe the operation of a bong?
I think the term describing the initial process of separation of the solid phase (dust particles) from the gas phase via bubbling is a wet scrubbing process.
On an industrial scale, it's more ...
- 36.9k
Only top scored, non community-wiki answers of a minimum length are eligible