Often after an acute injury of the knee the quadriceps muscle will not contract, which is called âquad inhibition.â. Inability to straighten the leg. Athletes with acute patellar injuries may find that they cannot flex the knee joint fully or straighten the leg. This may be exacerbated by swelling of the knee.
The alkali metals are a group (column) in the periodic table consisting of the chemical elements lithium (Li), sodium (Na), potassium (K), rubidium (Rb), caesium (Cs), and francium (Fr).
Examples of alkali metals: lithium (Li), sodium (Na), potassium (K), rubidium (Rb), ceasium (Cs), and francium (Fr). Although Hydrogen, is a member of group sometimes exhibit the properties of alkali metals.Examples of halogens are Fluorine (F), Chlorine (Cl), Bromine (Br) and Iodine (I).eactivity of Alkali Metals and Halogens In the outermost (s) shell of the alkali metals, they have 1 electron, by loosing that electron, the alkali metals get the stable electronic configuration.