Afictional element has two isotopes, each making up 50% of the population. isotope 1 has a mass of 60.0 amu, isotope 2 has a mass of 65.0 amu. calculate the atomic mass of the fictional element.

The number to the right of an element's symbol (ex. c-12) identifies the of an isotope.

Nebulae are enormous clouds in outer space. they are made mostly of hydrogen gas, helium gas, and dust. some nebulae glow brightly, while others do not. the stars that people see are huge, bright balls of glowing gas. they are made mostly of hydrogen and helium. which statement correctly describes other ways in which nebulae and stars are different? a. stars can form inside a nebula but a nebula can never be produced by any star. b. a star always has a higher density than a nebula. c. stars can never form inside a nebula but a nebula can be produced by any star. d. a nebula always has a higher density than a star.

According to the kinetic-molecular theory, what happens to a liquid when it is transferred from one container to another? the volume and the shape stay the same. the volume increases to fill the new container, but the shape stays the same. the volume stays the same, but the shape changes to fit the new container. the volume and the shape change to fill the new container.