This is so because animals cannot make their own food and so they get it from plants which are the only organism that make their own food. What animals get from food is energy and the source of energy is the sun. Since they can't collect the suns energy on their own they depend on … Read more

Volcanoes have a negative and positive effect on our environment. The high content of sulphur makes the air not suitable for inhalation but the soil around volcanoes is very fertile. Also volcanoes form new land masses. Also volcanoes heat underground water thus producing hot springs and geysers 

Hydrogen by itself is a positive ion when combined but when in compounds such as hydroxide or hydrogen carbonate it is a negative ion