One hectare comprises between 1.2 and 1.6 football pitches, as soccer fields are known in British English. An internationally-sanctioned soccer field is 100 to 110 meters in length by 64 to 75 meters in width, comprising between 0.62 and 0.82 hectares depending on the field. Keep Learning.
From Wikipedia, the free encyclopedia. Alkaliâaggregate reaction is a term mainly referring to a reaction which occurs over time in concrete between the highly alkaline cement paste and non-crystalline silicon dioxide, which is found in many common aggregates.he alkaliâaggregate reaction is a general, but relatively vague, expression which can lead to confusion. More precise definitions include the following: 1  Alkaliâsilica reaction (ASR, the most common reaction of this type); 2  Alkaliâsilicate reaction, and; 3  Alkaliâcarbonate reaction.
noun, plural alkalis, alkalies. 1. Chemistry. any of various bases, the hydroxides of the alkali metals and of ammonium, that neutralize acids to form salts and turn red litmus paper blue. any of various other more or less active bases, as calcium hydroxide. (not in technical use) an alkali metal.