What does pH measure? number of hydrogen atoms in an acid number of hydroxide atoms in a base concentration of hydrogen ions in solution concentration of hydroxide ions in solution

Explain how carbon monoxide can cause death

Plz choose one of the compounds from the table and explain how you know the numbers of atoms in your formula. is it possible for two different compounds to be made from the exact same two elements? why or why not? with a limited number of elements (less than 120 are known), does this mean we also have a small number of compounds or do we have a large number of compounds in this world?

Why is the melting of ice a physical change ?