MCB 150 Chapter Notes - Chapter 2: Kinetic Energy, Disulfide, Aldehyde

• School: University of Illinois
• Department: Molecular and Cell Biology
• Course: MCB 150
• Professor: Brad Mehrtens

Document Summary

Molecules with different structures will react differently in the body. Atomic weight - average of all the mass numbers of the naturally occurring. Isotopes - atoms with different number of neutrons isotopes. Radioactive isotope - an unstable isotope that will release nuclear radiation. Dalton - unit of weight for atoms (neutron and proton are 1 dalton) Electrons move around the nucleus in orbitals. Orbitals are grouped into groups called electron shells. The smaller the number, the closer to the nucleus. Valence shell - outermost shell of electrons. Valence electrons - electrons in the valence shell. Chemical bonds - forces that hold atoms together. Cations - positive ions that have lost a electron. Molecules - substances held together by covalent bonds. Nonpolar covalent bond - when electrons are shared equally. Polar covalent bond - when electrons are not shared equally, thus forming a polar molecule. Molecular formulas - only indicate numbers and types of atoms.