Finding percent composition is fairly easy. You only need to divide the mass of an element by the total mass of the compound. We can do this one element at a time.
First, let's find the total mass by using the masses of the elements given on the periodic table.
7 x 12.011 (mass of Carbon) = 84.077
5 x 1.008 (mass of Hydrogen) = 5.04
3 x 14.007 (mass of Nitrogen) = 42.021
6 x 15.999 (mass of Oxygen) = 95.994
Add all of those pieces together.
84.077 + 5.04 + 42.021 + 95.994 = 227.132 g/mol is your total. Since we also just found the mass of each individual element, the next step will be very easy.
Carbon: 84.077 / 227.132 = 0.37016 ≈ 37.01 %
Hydrogen: 5.04 / 227.132 = 0.022189 ≈ 2.22 %
Nitrogen: 42.021 / 227.132 = 0.185 ≈ 18.5 %
Oxygen: 95.994 / 227.132 = 0.42263 ≈ 42.26 %
You can check your work by making sure they add up to 100%. The ones I just found add up to 99.99, which is close enough. A small difference (no more than 0.03 in my experience) is just a matter of where you rounded your numbers.
Separate the components of a mixture.
1. Thermoplastics
2. Thermosetting plastics
4. Nylon
5. Thermoplastics like polythene
6. Thermosetting plastics like melamine
7. Natural
8. Raw
11. Light and durable
13. repeating subunits
14. Naturally from silkworms
15. Thermoplastics
16. Air and water
17. Less-reactive
18. Poly-tetra-fluoroethylene ptfe
Answer:
Approximately 
.
Explanation:
The gallium here is likely to be produced from a 
solution using electrolysis. However, the problem did not provide a chemical equation for that process. How many electrons will it take to produce one mole of gallium?
Note the Roman Numeral "
" next to 
. This numeral indicates that the oxidation state of the gallium in this solution is equal to 
. In other words, each gallium atom is three electrons short from being neutral. It would take three electrons to reduce one of these atoms to its neutral, metallic state in the form of 
.
As a result, it would take three moles of electrons to deposit one mole of gallium atoms from this gallium solution.
How many electrons are supplied? Start by finding the charge on all the electrons in the unit coulomb. Make sure all values are in their standard units.
.
.
Calculate the number of electrons in moles using the Faraday's constant. This constant gives the size of the charge (in coulombs) on each mole of electrons.
.
It takes three moles of electrons to deposit one mole of gallium atoms . As a result, 
of electrons would deposit 
of gallium atoms .
I believe the atomic level increases hope this helps.
