RELATED PRODUCTS. This value kit includes 12 20 Amp Single-Pole This value kit includes 12 20 Amp Single-Pole 1 30 Amp Double-Pole 1 50 Amp Double-Pole THQP 1/2 in. Circuit Breakers. The load center includes a sturdy tin-plated copper buss bar and a galvanized box for increased durability and reliability.
An element is a substance consisting of atoms which all have the same number of protons-i.e. the same atomic number. Elements are chemically the simplest substances and hence cannot be broken down using chemical methods. Elements can only be changed into other elements using nuclear methods. Although an element's atoms must all have the same number of protons, they can have different numbers of neutrons and hence different masses.
An isotope is a particular form of an element. The atoms of one isotope of an element differ from those of another isotope of the same element primarily in the number of neutrons in their nuclei. (They all have the same number for both protons and electrons.)