What is the charge on the cation in the ionic compound sodium sulfide?

Does the temperature affect the solubility of sugar and salt in water? if it does tell me like different temperatures with different solubilities so i can sketch down a graph

Which rate indicates the number of children that would be born per woman if she were to live to the end of her child bearing years

What is a substance? a. a physical property of matter b. a chemical property of matter c. an element or compound that cannot be physically separated d. characteristics used to tell the difference between mixtures