No elements visible!
Ions form between metals and non-metals.
Hope this helps!
Answer: KMnO4-
Explanation:
You're looking at one potassium plus a polyatomic ion.
So K plus MnO4, equals:
KMnO4-
It also has a molar mass of 158.04 g/mol, I don't know if you need that, but I thought it would be nice to include it.
Answer: last option, what came before the big bang?
Explanation:
The big bang theory states that the universe started as a dense nucleus of matter: a huge amount of matter concentrated in a tiny spot.
This is the conclusion of equations and evidences that prove that the universe has been and continuous to expand: since it has been expanding, there was a moment when it was as small and dense as it is possible.
So, the expansion is the result of violent explosion.
The time during which the expansion has been happening (this is how long ago the big bang occured) has been estimated thanks the the observation of the speed of recesion of the galaxies, but nothing can be told about what came before the bing bang occured.
Negative is bad and positive is good
Answer:


Explanation:
Hola.
En este caso, para calcular la longitud (a) de una cara de celda unitaria, consideramos la siguiente ecuación:

En la que consideramos el número de átomos por celda (4 para FCC), la masa molar (40.3 g/mol para MgO) y el número de avogadro para obtener:

Despejando para a, obtenemos:
![a^3 = \frac{4atom/celda*40.3g/mol}{3.581g/cm^3*6.02x10^{23}atom/mol}\\\\a=\sqrt[3]{7.478cm^3} \\\\a=4.213cm](https://tex.z-dn.net/?f=a%5E3%20%3D%20%5Cfrac%7B4atom%2Fcelda%2A40.3g%2Fmol%7D%7B3.581g%2Fcm%5E3%2A6.02x10%5E%7B23%7Datom%2Fmol%7D%5C%5C%5C%5Ca%3D%5Csqrt%5B3%5D%7B7.478cm%5E3%7D%20%5C%5C%5C%5Ca%3D4.213cm)
Finalmente, el radio lo calculamos como:

¡Saludos!