Answer:
is a naturally occurring hydrocarbon gas mixture consisting primarily of methane, but commonly including varying amounts of other higher alkanes, and sometimes a small percentage of carbon dioxide, nitrogen, hydrogen sulfide, or helium.
It is formed when layers of decomposing plant and animal matter are exposed to intense heat and pressure under the surface of the Earth over millions of years. The energy that the plants originally obtained from the sun is stored in the form of chemical bonds in the gas
for heating, cooking, and electricity generation. It is also used as a fuel for vehicles and as a chemical feedstock in the manufacture of plastics and other commercially important organic chemicals.
A. The minimum amount of energy required to remove one electron from an atom.
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.
Answer:
1. Sound is a energy (mechanical)produced by vibrating objects and sound energy is movement of energy through particles.
2.Space occupied by the substance
3.<u>Propagation</u> of <u>Sound Wave</u> and <u>particles of the medium</u>
4.High-Frequency(Ultrasonic wave)
Explanation:
1.Sound is the form of energy which causes sensation of hearing to our ear.It is produce by vibrating objects. When the objects vibrate(to and fro motion) ,they pushes the particles of medium creating the region of high density called compression .When the particles moves backward ,they creates a region of low density called Rarefaction.This pattern repeats indefinitely.
2.Volume is the quantity of three dimensional space occupied by substances like solid,liquid and gases. The SI unit of volume is

In metric system unit of volume is liter
3. Longitudinal Waves: Waves in which displacement of the medium particles are parallel(in the same direction) to the propagation of wave.
Sound wave is longitudinal wave.Hence its particles moves in the same direction as the wave (energy)travel.
4.Frequency: The number of times sound wave passes a given point in one second.Its SI unit is Hertz(Hz).
Frequency of vibration decides the Pitch of the sound waves producing them.
A sound wave of High Pitch means it is oscillating rapidly(at high speed).These are also called Ultrasonic waves. These have frequency more than 20000 Hz. Human being can't hear ultrasonic waves.
It’s the second one if you need more help tell me