<span>Gather your materials. Gather the sand, salt and iron filing mixture; a magnet; a paper towel; a cup of warm water; an empty cup; and a piece of filter paper.Use the magnet to remove the iron. ...Use warm water to dissolve the salt. ...<span>Remove the sand from the salt water.</span></span>
To answer this question, we can use the following equation:

where e is the energy change, h is Planck's constant, c is the speed of light (m/s), and lambda is wavelength in meters. So then we can plug in the information:



So the energy that is omitted by the atom is
.
Answer: 
Explanation:
Electrolysis of a subastance is breaking it into its constituents by the action of electrical current.
In the electrolysis of molten sodium chloride, sodium metal is produced at the cathode which is a negative electrode and chlorine gas produces as the anode which is a positive electrode.

At anode : 
At cathode : 
Answer:
Calcium
Explanation:
Hi!
So, the best way to solve this is with a period table with all of the sublevels labeled. (check below)
So the s sublevel starts at 1s which is Hydrogen. If you go down 4 rows, or periods, you get to sublevels 4s. As you should know, as you go across groups/columns, the valence electrons get higher. So the element that you are looking for has 2 valence electrons. So, the element you are looking for should be 4 down and 1 right of Hydrogen which is: Calcium
I hope I helped and have a wonderful evening!
The coins in 1991 had more copper in them compared to the coins today. So, that is why it worth 3.3p.