Your doctor may need to change the doses of your medications or monitor you carefully for side effects. ... Metformin side effects can also affect other parts of the body. It can leave a metallic taste in the mouth, cause heartburn or headache, flushing of the skin, nail changes or muscle pain. More serious metformin side effects include chest pain or rash. ...
Early String Theory. The first attempt to construct a physical model of an atom was made by William Thomson (later elevated to Lord Kelvin) in 1867. The most striking property of the atom was its permanence.
Modern Atomic Theory (John Dalton) Experiments with gases that first became possible at the turn of the nineteenth century led John Dalton in 1803 to propose a modern theory of the atom based on the following assumptions. 1. Matter is made up of atoms that are indivisible and indestructible. 2. All atoms of an element are identical. 3.