Answer:
The plum-pudding model proposed that an atom is composed of negatively-charged particles floating within a sea of positive charges. This sea of positive charges served to counterbalance the negative charge on the electrons so that the atom remains neutral.
Explanation:
J.J. Thompson from experiments he conducted with the rays produced from a cathode tube to which a high voltage is applied across its two ends, discovered that these rays were negatively charged and had a mass much much smaller than the mass of any known atom. These negatively-charged rays were later called electrons. Since the atom was neutral in charge overall, J.J. Thompson then proposed the plum-pudding model.
The plum-pudding model proposed that an atom is composed of negatively-charged particles floating within a sea of positive charges. This sea of positive charges served to counterbalance the negative charge on the electrons so that the atom remains neutral. The name of this model was chosen because it resembled the English dessert, plum-pudding.
Answer:
molar mass M(s) = 65.326 g/mol
Explanation:
- M(s) + H2SO4(aq) → MSO4(aq) + H2(g)
∴ VH2(g) = 231 mL = 0.231 L
∴ P atm = 1.0079 bar
∴ PvH2O(25°C) = 0.03167 bar
Graham´s law:
⇒ PH2(g) = P atm - PvH2O(25°C)
⇒ PH2(g) = 1.0079 bar - 0.03167 bar = 0.97623 bar = 0.9635 atm
∴ nH2(g) = PV/RT
⇒ nH2(g) = ((0.9635 atm)(0.231 L))/((0.082 atmL/Kmol)(298 K))
⇒ nH2(g) = 9.1082 E-3 mol
⇒ n M(s) = ( 9.1082 E-3 mol H2(g) )(mol M(s)/mol H2(g))
⇒ n M(s) = 9.1082 E-3 mol
∴ molar mass M(s) [=] g/mol
⇒ molar mass M(s) = (0.595 g) / (9.1082 E-3 mol)
⇒ molar mass M(s) = 65.326 g/mol
I believe it lies in the 3rd Quadrent
