Answer:
C. Lose three electrons to have a full outer shell
Explanation:
Al is in Group 13 of the Periodic Table, so it has three valence electrons.
It must either lose three electrons or gain five to achieve a stable octet.
It is easier to lose three electrons than it is to gain five, so Al loses three electrons.
D. is wrong, for the same reason.
A. is wrong. If Al lost three electrons, it would be breaking into a stable inner shell.
C. is wrong. Al is a metal, so it will lose electrons in a reaction.
Hello!
The number of 20-g ice cubes required to absorb 47 kJ from a glass of water upon melting is 7 icecubes
Why?
We are going to clear from the equation of the released heat, the mass of ice (m). The specific latent heat of fusion of ice is 336 kJ/kg:

So, 7 ice cubes are required to absorb that amount of heat from the glass of water.
Have a nice day!
Answer:
1.2 ( two significant digits)
Explanation:
5.4 - 4.21 answer should only have the the number of significant digits as the number in the equation with the least number of significant digits... in this case 5.4 is only two significant digits....so the answer should only have two significant digits
5.4 - 4.21 = 1.19 round to two digits = 1.2
The answer to your question is nitrogen dioxide