The atomic mass of the most common isotope of carbon is
the element with an atomic number of 4 is
exist in orbitals around the nucleus.
oxygen has protons in the nucleus.
an isotope of an element has the same number of protons but a different number of

Ascientist is investigating the effects of salinity on fish development. he places fertilized fish eggs in an aquarium that contains low salinity and observes their development. what factor would improve experimental design the most? place the fish eggs in the open ocean because that is the natural habitat include another aquarium that has normal salinity to compare to the low salinity aquarium include an aquarium that replaces salt with sugar to confirm that the effects are specific to salt grow algae with the fish eggs in order to provide adequate nutrients to the developing embryos