When an incandescent lightbulb is turned on, about 0.50 C of charge moves through the filament each second. How many electrons are flowing t

1 electron has a charge of 1.602176565×10⁻¹⁹ C so 1 C represents 10¹⁹/1.602176565 electrons

0.5 C represents 0.5*10¹⁹/1.602176565 electrons 

$${\frac{{\mathtt{0.5}}{\mathtt{\,\times\,}}{{\mathtt{10}}}^{\left({\mathtt{19}}\right)}}{{\mathtt{1.602\: \!176\: \!565}}}} = {\mathtt{3\,120\,754\,671\,630\,089\,658.688\: \!772\: \!544\: \!866\: \!177\: \!1}}$$

or approximately 3*10¹⁸ electrons.

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