An isotope of yttrium has 39 protons and 59 neutrons. What is the mass number of that isotope?

Remember to use the proper number of significant figures and leading zeros in all calculations.gelatin has a density of 1.27 g/cm³. if you have a blob of gelatin dessert that fills a 2.0 liter bottle, what is its mass? 2540 g2500 g3.9 x 10-43.937x 10-4

What is the molar mass of a gas that has density of 2.054 g/l

If i add water to oil what will happen