Questions tagged [atoms]
Smallest particle still characterizing a chemical element. It consists of a small nucleus charged positively, carrying almost all of the atom's mass, with electrons surrounding it. This tag should be applied to questions that specifically concern atoms or their properties. For the charged particles, please use [ions] instead. If your question is specifically about [protons], [neutrons], or [electrons], use those tags instead.
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The last element's atomic number
I was just thinking what can be the last atomic number that can exist within the range of permissible radioactivity limit and considering all other factors in quantum physics and chemical factors.
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How do I calculate the change in energy of an electron transition?
What are the $\Delta E$'s of the transitions of an electron from $n=5$ to $n=1$ and from $n=5$ to $n=2$ in a Bohr hydrogen atom? The wavelength of the first electron transition is $\lambda_1=409~\...
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Why is the ionization enthalpy of francium greater than that of cesium?
Why is the ionization enthalpy of francium greater than that of cesium, even though it has a larger size? I found no Google result regarding this.
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Is there an easy way to find number of valence electrons"
I want an high-school level answer. What I mean with "valence electrons" is the outermost electrons in that atoms' electronic arrangement? For example, 3 in an atom with an electronic arrangement of 2,...
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Types of radioactive decay
Besides alpha, beta, and gamma, are there any other types of radioactive decay? If so, what are they? Is there any type of radioactive decay that is more powerful than gamma?
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How many electrons can each shell in an atom hold?
I know that the first shell can hold up to 2, the second and third can hold up to 8, and the fourth 18. But what about after that?
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If atoms are mostly empty space then how are we able to interact with things?
Note: This question has come out of curiosity
Q: We all have read that atoms are mostly empty, they are generally compared to a football stadium in which a pea is kept in the center (nucleus) and ...
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What are the known atomic oxygen species?
I'm interested in chemical reaction mechanisms with more exotic particles. The Wikipedia page seems to imply that the normal atomic oxygen is $O(^3P)$, is that right?
I also came across $O(^1D),O(^1S),...
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Atomic properties [closed]
This may be a very broad question.
I always asked myself how scientists manage to find out the exact molecular structures of for instance water or carbohydrates. How do they know? How do they know the ...
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In nuclear chemistry, how does a neutron split to form a proton and an electron?
I'm studying radioisotopes at the moment and balancing nuclear reactions isn't making sense in that more matter is coming out of the equation in negative β⁻ decay equations:
$$\ce{_6^{14}C -> _7^{...
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Wasn't Rutherford's assumption of gold foil to be made of single layer wrong?
My teacher taught about Rutherford's gold foil experiment today. Sir said that, Rutherford used gold foil of thickness $10^{-7}$ m and concluded atom to be of size $10^{-10}$ m. Sir also said that ...
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How will these hydrogen atoms interact?
Assume that we have a space with just two $\ce{H}$ atoms and their distance to each other is $d$. Let's say they don't have initial velocity. What is the force with which they will act on each other?
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Magnetic moment of coordination complexes?
To understand the commonly quoted magnetic values of coordination complexes (central ion) we use
$$m_l=\sqrt{n(n+2)} \text{BM where BM}=\frac{e\hbar}{2m_e}\text{JT}^{-1}$$
$n$=number of unpaired ...
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Understanding Moseley’s law from the Rydberg-type equation?
To explain the characteristic X-ray emission peaks for various elemental targets, a formula was developed which was similar in construct to the Rydberg equation for H-atom as derived by the Bohr-model....
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Are orbitals always filled in from closest to nucleus to farthest away?
In which orbital, 4f or 6s, would an electron have a greater likelihood of being near the nucleus.
I figured that the 6s would be closest, since it is filled in first when using the Aufbau principle.
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Is ionic bond just formed by "electrostatic" interaction between two oppositely charged ions?
According to the definition of ionic bond:
An ionic bond is a type of chemical bond formed through an electrostatic attraction between two oppositely charged ions.
If we consider the above ...
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How do 1s and 2p orbitals overlap?
In the following figure
we can see that the p-orbitals overlap 1s orbital (though relatively very little). How can an electron in p-orbital, be simultaneously in the 1s orbital at any given point ...
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Why do people still use the mole (unit) in chemistry?
I know that the mole is widely used in chemistry instead of units of mass or volume as a convenient way to express amounts of reactants or of products of chemical reactions.
I'm wondering why people ...
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Finding the number of orbitals on a central atom
In $\ce{BeCl2}$ the number of orbitals on central atom, i.e. on beryllium, are 2. In $\ce{BF3}$, the number of orbitals on central atom , i.e. on boron, are 3.
Similarly in $\ce{NH3}$ there are 4, ...
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What determines the density of an element?
I used to be under the (wrong) assumption that the density of an element correlates with it's atomic number $\mathrm{Z}$, I thought that since having more protons meant the atom weighed more; but of ...
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Sulfur trioxide - vacant d-orbitals
Sulfur trioxide violates the octet rule. Upon drawing the Lewis dot structure for sulfur trioxide, we see that the central sulfur atom is bonded to three other oxygen atoms by double covalent bonds. ...
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Storing kinetic energy in bonds
Let's assume a setup with a static linear molecule with three identical atoms connected by bonds and a single atom, identical to the other three, being shot at the molecule. Let's also assume that ...
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How to find the number of valence electrons?
I need to understand the following:
Considering an element Sulfur - S which has 16 electrons.
How do we calculate the number of valence electrons of S?
Please correct me if I am wrong:2+2+6+2+4=16. ...
Shounak Bhattacharya
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(Organic Chemistry) Common Atoms in Organic Molecules [closed]
What are 6 atoms commonly found in organic molecules?
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Z* effective charge and Ionization Energy
I'm trying to figure out the patterns for Ionization Energies. I am familiar with the periodic trend, however things become quite different when we hit the 1st I.E. For example, Na has an I.E(1) of ...
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How do the differences in the number of protons result in such great differences in elemental properties?
I understand(I think) the mass and density aspect, i.e. the more protons you have, the more the element weighs, also the denser the atom is. What about everything else(color, for example)? Elements ...
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Degeneracy of orbitals?
Why is that in an external magnetic field(uniform) the degeneracy of d,f orbitals is lost but the degeneracy of p orbitals remain intact if the main cause of losing degeneracy is the difference in ...
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Confusion about the charge of electrons while orbiting through bohr's energy shells
I came across the following part in my text book. Bohr's atomic theory explained the stability of an atom by the idea of energy shells. He said that while orbiting the nucleus through a particular ...
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Can there exist any element with an 8th principal shell?
I am a high school student. While studying the atomic structure a question appeared to me. We know that an atom can have the highest limit of 7 Bohr energy shells or principal energy shells, ...
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How to get the valencies of elements?
How to find the valencies of elements by using its distribution of electrons?
Please explain the method in simple words. Do you have to study the valencies or is there a simple way of remembering?
PS:...
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How does the reaction Mg + O₂ → MgO occur? [closed]
$\ce{Mg + O2 → MgO}$
Magnesium, oxygen and magnesium oxide form the above equation.
How?
What do I need to learn to do this? atomic numbers/ valencies?
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Why can't we use fusion to make ourselves rich?
As we know on fusing two hydrogen atoms we can convert it to helium and by breaking them we get two $\ce{H}$ atoms. So why can't we convert mercury to gold by removing 1 proton per atom?
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What are the g-block's predicted properties?
I have been researching for a Physics/Chemistry exam and thought; what will the future periods in the periodic table (periods 8 and above) would entail? Each block contains its own properties that ...
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Why is the relative atomic mass of carbon not exactly 12?
Relative atomic masses of atoms of all chemical elements are numbers without units, being the value of proportion compared to $\frac{1}{12}^\text{th}$ the mass of the carbon atom.
But the relative ...
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List in order of increasing radius
List in order of increasing radius:
a) Rb, K, C5, Kr
For this one I got C, Kr, K, Rb
b) Ar, Cs, Si, Al
This I got: Ar, Si, Al, Cs
Does anyone know if this is correct? I don't have the solution ...
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Why do single, double and triple bonds repel each other equal amounts?
I'm here to share with you something that totally confuses me, as I can't see the logic behind it, and my teacher doesn't know either.
Let's take a set of bonds that's trigonal pyramidal, with a lone ...
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Energy of the n-th level for an atom
Going through the Bohr's model and his assumptions, I came across with this formula to find the energy of the n-th level of any atom:
$$E = - \frac{Z k_e e^2}{2r_n} = -\frac{Z^2(k_e e^2)^2m_e}{2\...
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Why are atoms with eight electrons in the outer shell extremely stable?
Atoms that have eight electrons in their outer shell are extremely stable. It can't be because both the $s$ and the $p$ orbitals are full, because then an atom with 13 or 18 valence electrons would be ...
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What is a neutral atom?
I was told that an atom's atomic number is defined as follows:
The number of electrons or protons present in a neutral atom is called atomic number. It is represented by ...
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What is the difference between physical and chemical bonds?
If you characterize the chemical bonds to two categories physical and chemical bonds, how do you do it? Aren't all bonds chemical and physical?
From the freedictionary.com, chemical bond:
Any of ...
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Why are there two Hydrogen atoms on some periodic tables?
Most periodic tables only feature one Hydrogen atom, on the top of the first group. But some, like the one I was given, also show Hydrogen in the 7th group, to left of Helium.
Why are there two ...
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Why do atoms generally become smaller as one moves left to right across a period?
It seems to me that the addition of electrons and protons as you move across a period would cause an atom to become larger. However, I'm told it gets smaller. Why is this?
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