Answer is: the discovery of sub atomic particles like electrons.
J. J. Thomson discovered the electron in 1897.
His "plum pudding" model (1904) suggested: the electrons are embedded in the positive charge.
With this model, he abandoned his earlier hypothesis (the atom was composed of immaterial vortices).
J.J. Thomson placed two oppositely charged electric plates around the cathode ray. He did experiments using different metals as electrode materials and found that the properties of the cathode ray remained constant no matter what cathode material he used.
Tomson concluded that atoms are divisible and that the corpuscles are their building blocks (atoms are made up of smaller particles).
The formula of compound is LiClO4.3H2O
<em><u>calculation</u></em>
- <em><u> </u></em>find the mole of each element
that is moles for Li,Cl,O and that of H2O
- moles = % composition/ molar mass
For Li = 4.330/ 6.94 g/mol= 0.624 moles
Cl=22.10/35.5=0.623 moles
39.89/16 g/mol =2.493 moles
H20= 33.69/18 g/mol= 1.872 moles
- find the mole ratio by dividing each moles by smallest number of mole ( 0.624 moles)
that is for Li= 0.624/0.623= 1
Cl= 0.623/0.623=1
O = 2.493/0.623 =4
H2O= 1.872/0.623=3
<h3>Therefore the formula=LiClO4.3H2O</h3><h3 />
I think the best answer from the choices listed above is option B. The best graduated cylinder for this case is the glass cylinder. A metal cylinder is not possible because you cannot measure really since metals are not transparent. A plastic cylinder cannot also be used since the substance should be heated for the experiment.
Those are both correct! great job, keep up the good work (-: