If the period indicates the number of atomic shells, and the atomic number indicates the number of electrons, why is calcium in the fourth period? That doesn't make sense, does it? Because 20 electrons don't need four shells?
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Loading...How do you write an equation for oxidation, reduction, and especially redox reactions? Feel free to send me links to well-explained videos. I need help! I'm grateful for any answers!
Good evening, Unfortunately, I don't understand this chemistry text at all. I've never seen this notation before in my life, and I don't even know what an isotope is. This is my first year of chemistry, and I've never had chemistry before. What is this notation for, with the mass number and atomic number before…
e.g. iron: Why are 4s2 released first to form Fe2+? And why is this stable? This does not create a full or half-full d-orbital, nor does it lower the energy level, since the 3d orbital has a higher energy than the 4s orbital.
The formed hydroxide ions further react through a neutralization reaction with the hydronium ion (H3O^+) from the acetic acid, which is formed by the reaction of acetic acid with water, and are converted back to water. H3O+ + 2 OH- –> <– 2H2O how does this happen?
3.6g of water is dropped onto barium: Ba + 2 H2O ———> Ba(OH)2 + H2 How many grams of barium are used? What is the volume of the resulting gas under standard conditions (at 20 °C and 1013 hPa = 24 l/mol)?
You can only pack 18 electrons into the third shell if there are already 2 in the 4th. Otherwise go only 8.
Here you can see the boundaries of the shell model again.
So the model is fault? Because with 3 full shells and 2 valence electrons on the 4th, would it be a total of 40 electrons?
The third is already “full” with 8 and will only be extended if it is no longer the outer shell. Only 8.
And yes, the model comes to its limits. Because there are no real shells in an atom. This order of occupation can only be explained with the orbital model.
2-8-8-2, [Ar]4s^2
Does it fit?
but do not have to be on the 3rd Stage 18 electrons
The miracles of chemistry 🙂
The 10 3d electrons are energetically between 4s and 4p
because I thought the 3rd had to be full?
The occupation always takes place according to the energy level of the respective electron energetically more favorable first and the 4s are cheaper than the 3d and are therefore only occupied.
“Shales” are just a model construct and the more you align the model with reality, the more you have to bend it.
ok thanks so it’s easy to change nix