Answer:
1 molecule of oxygen has 2 atoms.
So 2,25 molecules of oxygen have 2 x 2,25 atoms.
2 x 2,25 = 4,5 atoms
There are 4,5 atoms in 2,25 molecules oxygen.
a) Group 2 elements have 2 electrons on their outer shell, so they form a 2+ charge.
b) they lose 2 electrons as they are transferred to the non metal.
c)They obtain this charge as when they are made into an ionic compound the 2 electrons on the outer shell are transferred to the non metal, meaning there are 2 more protons that electrons, giving it a positive charge.
hope this helps! :)
The answer is A. It is an alkyn. There is a triple bond
Your answer is the last option, the explosion of fireworks. This is because all of the other options are physical changes because they don't change the substance, they only affect it in some way. However the explosion of a firework clearly changes a substance inside the initial 'rocket' into fireworks.
I hope this helps!