If an ion has three more electrons than protons

Explain why pure hydrogen cyanide does not conduct electricity, but become a conductor when it is dissolved in water? (at room temp, pure hcn exists as a volatile liquid)

The chart shows the bid provided by four contractors to complete a job. which contractor is the most cost-effective?

Calculate the number of kilojoules to warm 125 g of iron from 23.5°c to 78.0°c.