What does the law of conservation of matter show?

If equal masses of the listed metals were collected , which would have a greatest volume ? a. aluminum 2.70,b.zinc7.14,c.copper 8.92,d.lead 11.34

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)

How hot is the suns corona? (integrated science)