Naturally occurring Rubidium is made up of two isotopes. Rubidium-85 has a mass of 84.9117 amu and Rubidium-87 has a mass o 86.9100 amu. Rubidium-85 makes up 72.15% 0f naturally occurring Rubidium. calculate the atomic weight(atomic mass) of element Rubidium.

This chart lists four kinds of polymers and their sources. what can be known about all four polymers, despite their differences? they come from living things. they share ionic carbon bonds. they are at least 100 monomers long. they are made of repeating subunits.

Astudent reacts 13 moles of iron with 21 moles of oxygen according to the following equation:

Consider a culture medium on which only gram-positive organisms such as staphylococcus aureus colonies can grow due to an elevated nacl level. a yellow halo surrounds the growth, indicating the bacterium fermented a sugar in the medium, decreasing the ph as a result and changing the color of a ph indicator chemical. this type of medium would be referred to as a differential and enrichment culture.