Well if the change is reversible then it is a physical change, but if not then it is a chemical change.
Answer:
2M
Explanation:
M=mol/L
1. Find moles of CoCl2
mass of substance/molar mass = 130/129.833 = 1.001 mol
3. Substitute in molarity equation
M=(1.001/0.5)
M= around 2M
It looks all correct to me, great job!
Answer:
The first one has the weakest bond
Explanation:
The number of atoms together shows how strong the bonds in the second bond it is 4 bonds, the third is 8 bonds, the 4th one is 4 bonds thus why the first bond is the weakest.
D. 8
You can predict it from it's name "Octet" means Eight. Atom must have that number of electron to have a stable structure!
Hope this helps!