The law between the number of protons, neutrons, extranuclear electrons and relative atomic weight Anything else? Five

The law between the number of protons, neutrons, extranuclear electrons and relative atomic weight Anything else? Five

Number of nuclear charge = number of protons = number of extranuclear electrons = atomic number of protons + number of neutrons = = relative molecular mass an atom is composed of nucleus and extranuclear electrons, and nucleus is composed of protons and neutrons (not divided into two layers)

What is the atomic weight of aluminum

27

9. It is known that the chemical formula of metal element M (with only one valence) oxide is M2O3, then the chemical formula of its chloride is ()
Please explain the reasons and be more specific

(1) The chemical formula of oxide is M2O3
(2) Valence of metal element M - - + 3
(3) The chemical formula of its chloride is mci3

In the oxide of a metal element R, the mass ratio of R to oxygen is 9:8, and the relative atomic mass of R is 27
A. ROB. R2OC. R3O4D. R2O3

In the oxide of a metal element R, the mass ratio of R to oxygen is 9:8, and the relative atomic mass of R is 27. Suppose the chemical formula of the oxide is rxoy, then 27x: 16y = 9:8, X: y = 2:3, so the chemical formula of the oxide is r2o3

In the oxide of a metal element R, if the mass ratio of R to oxygen is 7:3 and the relative atomic mass of R is 56, the chemical formula of the oxide of R is ()
A. ROB. RO2C. R2O3D. R3O4

Suppose that the chemical formula of the oxide of metal element R is r2ox, according to the meaning of the title, we can get: (56 × 2): 16x = 7:3 & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; solve x = 3, so we can know that the chemical formula of the oxide of R is r2o3; so we choose C