Molar mass NaCl = 58.44 g/mol
number of moles:
mass NaCl / molar mass
145 / 58.44 => 2.4811 moles of NaCl
Volume = 3.45 L
Therefore :
M = moles / volume in liters:
M = 2.4811 / 3.45
M = 0.719 mol/L⁻¹
hope this helps!
Thomson's plum pudding model dictated that the atom contains negative charges surrounded by positive charges in close vicinity. Rutherford's experiment determined that the particles are not this close and the atom consists mainly of empty space and that it is the negative charge that surrounds the positive charge, not the other way around.
