Answer:
when lit, the atoms of different chemical compounds inside the firework absorb energy, when the electrons fall back to lower energy levels, they give off colored light. Depending upon the chemical used, different colors are produced. neon lights or signs are glass tubes filled with neon gas. When the light is plugged in, the electrical energy causes the electrons of neon to jump to higher energy levels, when they go to lower levels, colored light is given off. The neat thing is that the neon never gets used up. The only thing that gets used up is the electricity. The electrons don't get destroyed and can be used over and over again jumping levels. Neon glows with an orange light, but you know that neon signs can be lots of different colors. The variations come when different gases other than neon are used such as argon, or krypton or when the tube is painted so that with the light produced it produces a certain color.
Explanation:
Answer:
(a) 1s2 2s1
Explanation:
Electron configurations of atoms are in their ground state when the electrons completely fill each orbital before starting to fill the next orbital.
<h3><u>
Understanding the notation</u></h3>
It's important to know how to read and interpret the notation.
For example, the first part of option (a) says "1s2"
- The "1" means the first level or shell
- The "s" means in an s-orbital
- The "2" means there are 2 electrons in that orbital
<h3><u>
</u></h3><h3><u>
Other things to know about electron orbitals</u></h3>
It important to know which orbitals are in each shell:
- In level 1, there is only an s-orbital
- In level 2, there is an s-orbital and a p-orbital
- in level 3, there is an s-orbital, a p-orbital, and a d-orbital <em>(things get a little tricky when the d-orbitals get involved, but this problem is checking on the basic concept -- not the higher level trickery)</em>
So, it's also important to know how many electrons can be in each orbital in order to know if they are full or not. The electrons should fill up these orbitals for each level, in this order:
- s-orbitals can hold 2
- p-orbitals can hold 6
- d-orbitals can hold 10 <em>(but again, that's beyond the scope of this problem)</em>
<h3><u>
Examining how the electrons are filling the orbitals</u></h3>
<u>For option (a):</u>
- the 1s orbital is filled with 2, and
- the 2s orbital has a single electron in it with no other orbitals involved.
This is in it's ground state.
<u>For option (b):</u>
- the 1s orbital is filled with 2,
- the 2s orbital is filled with 2,
- the 2p orbital has 5 (short of a full 6), and
- the 3s orbital has a single electron in it.
Because the 3s orbital has an electron, but the lower 2p before it isn't full. This is NOT in it's ground state.
<u>For option (c):</u>
- the 1s orbital is filled with 2,
- the 2s orbital has 1 (short of a full 2), and
- the 2p orbital is filled with 6
Although the 2p orbital is full, since the 2s orbital before it was not yet full, this is NOT in it's ground state.
<u>For option (d):</u>
- the 1s orbital has 1 (short of a full 2), and
- the 2s orbital is filled with 2
Again, despite that the final orbital (in this case, the 2s orbital), is full, since the 1s orbital before it was not yet full, this is NOT in it's ground state.
<em>C = 0,75 mol/dm³</em>
<em>V = 500mL = 500cm³ = 0,5dm³</em>
C = n/V
n = 0,75×0,5dm³
<u>n = 0,375 moles</u>
<em>M NaCl: 23+35,5 = 58,5g</em>
1 mole ---------- 58,5g
0,375 ----------- X
X = 0,375×58,5
<u>X = 21,9375g NaCl</u>
:)
It’s, D. Kinetic Energy.
Explanation: Energy associated with an object’s motion is called kinetic energy. A speeding bullet, a walking person, and electromagnetic radiation like light all have kinetic energy.
Hope this helped ;)
The formula of ozone is O3.
Hope this helps~
