Question

about ______ molecules in a glass of water are dissociated.
1 in 5,000,000
1 in 1,000,000,000
1 in 1,000,000
1 in 2
1 in 500,000,000

Explanation:

Water is a covalent - bonded compound and only a very small fraction of its molecules dissociate. The auto - ionization of water is a rare event. The molarity of hydrogen ions in pure water is \(1\times10^{- 7}\ M\) at \(25^{\circ}C\), which means about 1 in 555,555,556 water molecules are dissociated. Among the given options, the closest value is 1 in 500,000,000.

Answer:

E. 1 in 500,000,000