Planets have the colors that they have because of what they are made of and how their surfaces and/or atmospheres reflect and absorb sunlight. Venus is entirely covered with a thick carbon dioxide atmosphere and sulphuric acid clouds which give it a light yellowish appearance.lanets have the colors that they have because of what they are made of and how their surfaces and/or atmospheres reflect and absorb sunlight. Venus is entirely covered with a thick carbon dioxide atmosphere and sulphuric acid clouds which give it a light yellowish appearance.
The mass number represents the number of protons plus neutrons in the nucleus of an atom of the element. The number of protons determines the element, but the number of neutrons in the atom of any one element can vary. Each variation is an isotope. About 20 radioactive isotopes of antimony are also known.A radioactive isotope is one that breaks apart and gives off some form of radiation. Radioactive isotopes are produced when very small particles are fired at atoms. These particles stick in the atoms and make them radioactive.he mass number represents the number of protons plus neutrons in the nucleus of an atom of the element. The number of protons determines the element, but the number of neutrons in the atom of any one element can vary. Each variation is an isotope. About 20 radioactive isotopes of antimony are also known.
Printable Version. Plutonium is a radioactive metallic element with the atomic number 94. It was discovered in 1940 by scientists studying how to split atoms to make atomic bombs. Plutonium is created in a reactor when uranium atoms absorb neutrons. Nearly all plutonium is man-made.Plutonium predominantly emits alpha particles â a type of radiation that is easily stopped and has a short range. It also emits neutrons, beta particles and gamma rays.lutonium is created in a reactor when uranium atoms absorb neutrons. Nearly all plutonium is man-made. Plutonium predominantly emits alpha particles â a type of radiation that is easily stopped and has a short range. It also emits neutrons, beta particles and gamma rays.