Consider sodium, which has an atomic number of 11 and an atomic mass of 23. How many valence electrons does it have?

Matter is (on the whole) NEUTRAL. If there are 10 nuclear protons, 10 fundamental positively charged particles, there are necessarily 10 electrons, 10 fundamental negatively charged particles associated with the...

The is the number of protons $("p"^+")$. In a neutral atom, the number of electrons $("e"^(-)")$ equals the number of protons. is the sum of the protons and neutrons $("n"^0")$...

for discussion on atomic radii of the transition metals.

Nitrogen is in Group V. It has 5 . Do I win £5-00?

Because chlorine has a high nuclear charge, it tends to be oxidizing, and form $Cl^-$ ions in the process.

Group 2 has two valance electrons. Group 18 would have 8 valance electrons. ( The 10 d electrons will drop down into the next lower shell and are...

This may seem a bit confusing when one looks at , since chlorine is the seventh element in its row, but iodine is the seventeenth. However, in the case of...

In terms of actual , there is literally only one example. You can consider that their oxidation states have never gotten higher than $+8$, except for Iridium: In terms...

And the zinc cation is $Zn^(2+)$. When the ions form a salt, clearly they form an electrically neutral species; and thus the formulation of the salt is $Zn_3P_2$. Each phosphorus...

We know that $1*mol$ contains $6.022xx10^23$ individual sodium atoms, and has a mass of $22.99*g$. And thus for $1.$ there is a $2*g$ mass of $Na$. For $2.$ there is...