The way you want to find the percent composition would be by breaking down the problem like so:
K= atomic mass of K which is 39.098
Mn = atomic mass of Mn which is 54.938
O= atomic mass of o which is 15.999
Then you want to add 39.098+ 54.938+ 15.999 and you get 110.035 which is the molar mass for KMnO
Then you want to take each molar mass and then divide it 110.035 and multiply by 100
Ex. K = 39.098/ 110.035 and the multiply what you get by a 100
You do this for the other elements as well good luck!
Answer:
Explanation:
A. The charge on an element is determined by the differences between the number of protons and electrons in an atom.
An atom will have no charges if the number of protons and electrons are the same.
- When an atom loses or gains electrons, the number of electrons will either decrease or increase
- if the number of electrons is more than the number of protons, the excess electrons is the charge on the atom. And this makes the atom become a negatively charged ion.
- if the number of electrons is lesser than the number of protons, the deficient electrons makes the atom a positively charged ion. The number of electrons by which the atom is deficient makes the atom a positively charged ion.
Charge = number of protons - number of electrons
B. Electrons form the charges they do because with the charge, they become stable like the noble gases.
The desire of every atom is to have stable electronic configuration like those of the noble gases.
A potassium atom with a configuration 2 8 8 1 will prefer to lose an electron to become an Argon atom making the ion stable.
Fluorine 20 (F - Atomic number 9 and atomic mass 20). Firstly we need to know what is beta decay. Beta decay occurs when one neutron changes into a proton and an electron therefore the atomic mass will remain the same as even though we loose a neutron it is replaced by a proton, the atomic number is always raised by 1 when one beta decay occurs. The produced electron is shot out of the nucleus at an incredible speed. This speedy electron we call a beta particle.
Ok now the reaction.
20 20 0
F -> Ne + e
9 10 -1
Remember the atomic number determines the nature of the element ( i.e what elemnt it is).
Hope this helps :).
Bohr's atomic model proposed that electrons move in specific orbits around the nucleus of an atom.
The number of moles of one substance given the amount in mass can be calculated by the use of the molar mass. This is the mass of a compound per 1 mol of the said substance. For, KCl the molar mass is 74.55 g/ mol
148 g / 74.55 g/mol = 2 mol KCl
Hope this answers the question. have a nice day.