Question

How much positive and negative charge is here in a cup of water?

Answer 1

Let one cup has $250ml$ of water.

The mass of one cup of water is given as,

$m=250g$

The number of moles of water in one cup of water is given as,

$n=\frac{250}{18}\times 6.02\times {10}^{23}$

$n=8.36\times {10}^{24}$

Since, the numbers of electrons or protons in one water molecule are $10$.

The positive charge is given as,

$q^{+}=10\times 8.36\times {10}^{24}\times 1.6\times {10}^{-19}$

$q^{+}=1.338\times {10}^{7}C$

Thus, in one cup of water there are $1.338\times {10}^{7}C$ positive charge and $-1.338\times {10}^{7}C$ negative charge .