Which one is harder, magnesium or calcium, and why?

The number of moles of a given mass of a substance can be found without knowing its molecular formula or molar mass. true false

Using the periodic table, complete the following. element: hydrogen symbol: h₂ molecular weight: g mass of one mole: g/mol

How many moles of sulfur dioxide are in 2.26 × 10^33 sulfur dioxide molecules?