One atom has 20 protons and a mass of 44. Another atom has 20 protons and a mass number of 40. What is the identity of these atoms? How do you account for the difference in mass numbers?

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