What elements does a bed contain?
A bed contains mainly carbon, hydrogen, and oxygen, but there are many other trace elements that can be present, and of course, not all beds are made of the same substances, there are many different ways to build a bed. Even such things as the floral pattern that may be decoratively printed on a mattress can use inks that contain small quantities of various heavy metals.
Elements do not contain chemical, but chemicals contain elements. Elements are singular things with a set of properties all their own. There are currently 118 different known elements. Chemicals, which there are thousands of, are made up of two or more elements. Na is sodium(poisonous) and Cl is chlorine(also poisonous). When these two elements combine, you get NACl, which is table salt(not poisonous) and has properties completely different than the two individual elements.
Elements contain only one type of atom (atoms with the same number of protons). Compounds contain more than one element, and thus contain atoms with different numbers of protons. Compounds can be converted into elements, but elements are not reducible to anything simpler (besides subatomic particles).