Pretty sure the answer is A, but you probably shouldn't use Brainly to answer test questions.
Answer:
between the 2 and the 3 shell
Explanation:
when a gain of energy is the displacement of the electrons in a layer of low-energy shell high-energy, and here we have the 2nd shell is the shell of low energy, and 3 shell the shell is high-energy.
The crackling sound Is mainly to do with chemistry, The fireworks are filled with lead oxide, which turns into lead atoms as the firework explodes and heat up—— whistling sounds, the whistle is down to the tube being narrow one, thus rockets make a whistling noise
Density=mass/volume
density=1.08
mass=?
volume=125ml
1.08=mass/125
mass=1.08x125
mass=1g
What helps me to balance equations is to list the elements i have on each side of the equation, and use tally marks to see what I have and don't have. Then when I'm done balancing, I tally again to make sure everything matches up.
On the left side, you have 1 Al, and 2 O. On the right side, 1 Al and 3 O.
In order for the equation to balance, you need to place a 2 in front of the AlO on the right side. This would make the Al have 2 atoms and the O have six. On the left side, you need to place a 2 in front of the Al and a 3 in front of the O, making it six. Left side: 2 Al's 6 O's. Right side: 2 Al's and 6 O's. Matches!
