I THINK 18 OR 21 I AM SORRY IF I AM WRONG BRO
Well, when an atom attains a stable valence electron, it means that the outer electrons are complete and so cannot attain any more electrons. For the first shell, it is complete when it has 2 electrons, the second shell is complete when it has 8 electrons, all the other shells also have a particular number when complete. Anyway, i believe the answer is HYDROGEN because when HYDROGEN combines with another atom of HYDROGEN, the outer shell is completed. This is because HYDROGEN has only 1 electron. If the two HYDROGENS, which both have 1 electron combine, they make the electrons 2, which is complete for the first shell, HYDROGEN ends in the first shell. Since the electrons become 2, the shell is at stable valence. In all the other options, this happens;
NEON- It has 10 electrons, 2 in the first shell and 8 in the second. So the the shells are already complete, so it can't bond with any thing, which is completely against the question.
RADON- Radon has 86 electrons.
HELIUM- Helium has 2 electrons, so the shell is already full, and cannot bond, so it goes against the question. The question says BY BONDING.
So the answer is definitely 4) HYDROGEN
Hope i helped. Have a nice day, by the way, i'm very sure it's hydrogen.
Nope. It is false. Temperature decreases as altitude increases.
<u>Answer: </u>The volume of the solution is 85.7 mL
<u>Explanation:</u>
Molarity is defined as the amount of solute expressed in the number of moles present per liter of solution. The units of molarity are mol/L. The formula used to calculate molarity:
.....(1)
We are given:
Molarity of solution = 0.600 M
Given mass of 
= 12.00 g
We know, molar mass of ![BaSO_4=[(1\times 137.33)+(1\times 32.07)+(4\times 16)]=233.4g/mol](https://tex.z-dn.net/?f=BaSO_4%3D%5B%281%5Ctimes%20137.33%29%2B%281%5Ctimes%2032.07%29%2B%284%5Ctimes%2016%29%5D%3D233.4g%2Fmol)
Putting values in equation 1, we get:
The rule of significant number that is applied for the problems having multiplication and division:
The least number of significant figures in any number of the problem determines the number of significant figures in the answer.
Here, the least number of significant figures is 3 that is determined by the number, 0.600. Thus, the answer must have these many significant figures only.
Hence, the volume of the solution is 85.7 mL
Distance and time is needed for determining speed
