Question

what ions are formed when water dissociates?
hydrogen ions ( h+ )
hydroxide ions ( oh- )
water (h2o)
both ..... hydrogen ions (h+ ) and hydroxide ions ( oh- )

Explanation:

Water undergoes self - ionization. The chemical equation for the dissociation of water is $H_2O
ightleftharpoons H^++OH^-$. So both hydrogen ions ($H^+$) and hydroxide ions ($OH^-$) are formed.

Answer:

D. both ...... hydrogen ions ($H^+$) and hydroxide ions ($OH^-$)