In 1869 Russian chemist DIMITRI MENDELEEV started the development of the periodic table,arranging chemical elements by atomic mass. He predicted the discovery of other elements and left spaces open in his periodic table for them. HOPE THIS HELPSS HAVE A GREAT DAY <333
Answer:
Mole fraction Ar = 0.31
Explanation:
Remember that the sum of the mole fractions in a mixture of gases = 1
Mole fraction = Moles from a gas / Total moles
Mole fraction N₂+ Mole fraction O₂+ Mole fraction SO₂+ Mole fraction CO₂ + Mole fraction Ar = 1
N₂ = 0.21
O₂= 0.16
CO₂ = 0.23
SO₂ = 0.09
Mole fraction Ar = 1 - 0.21 - 0.16 - 0.23 - 0.09
Mole fraction Ar = 0.31
Answer:
1) The volume occupied by an atom is composed of mainly empty space
2) Atoms have a very small, relatively dense, central nucleus that is positively charged
3) The region around the nucleus of an atom are orbited by negatively charged electrons in a the same fashion planets orbit around the Sun.
Explanation:
The selection of gold for the gold foil experiment was due to its ability to be rolled into extremely thin sheets such that it was expected for alpha particle to perforate or pass through the foil.
H 3 0 + is hydronium ion. OH- is hydroxide ion. H+ is hydrogen ion
I think its B have a good day