Water on earth can exist in all 3 states: solid, liquid, and gas.
Earth is just the right distance from the sun so that temperatures are ideal for living organisms.
Earth has a protective atmosphere shielding the planet from harmful UV and X rays.
Answer:
1. Isotope with mass number 39.
2. 39.02g/mol
Explanation:
1. The most common isotope is the isotope in the higher proportion, that is:
Isotope with mass number 39.
2. The average atomic mass is the sum of the masses times their abundance. For the element X:
Average atomic mass:
38*0.0967 + 39*0.7868 + 40*0.1134 + 41*0.0031
= 39.02g/mol
The mass of ONE mole is the same thing as the atomic mass, so the mass of one mole of Al is 26.99
Answer:
8.87 × 10⁻⁷ grams
Explanation:
Moles = No. of Particles / 6.022 × 10²³ Particles/mol
Moles = 4.95 × 10¹⁵ atoms / 6.022 × 10²³ atoms/mol
Moles = 8.22 × 10⁻⁹ mol
Also,
Mass = Moles × M.Mass
Mass = 8.22 × 10⁻⁹ mol × 107.87 g/mol
Mass = 8.87 × 10⁻⁷ grams
