Answer:
0.0250 g.
Explanation:
∵ no. of moles (n) = mass / molar mass.
<em>∴ mass of Vitamine C = (n)(molar mass)</em> = (0.000142 mol)(176.12 g/mol) = 0.02501 g = <em>0.0250 g. "three significant figures"</em>
C) Fluorine is the most reactive among halogens
Explanation:
Thomson's suggested the plum pudding model of the atom in which the atomic space is made up of electrons surround by positive charges.
Rutherford in his gold foil experiment revised the plum pudding model of the atom;
- He discovered that most of the alpha particles passed through the foil while a few of them were deflected back.
- To explain this observation, he suggested the atomic model of the atom.
- In this model, an atom is made up of a small positively charged center where nearly all the mass is concentrated.
- Surrounding the nucleus is the extranuclear part made up of electrons.
Convert 5.0 to 1027 an you should get your answer
