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.
Making magnesium carbonate: the formation of an insoluble salt in water. Class practical. When solutions of two soluble salts are mixed, a solid may form. This solid is called a precipitate, and the reaction is called a precipitation reaction. Precipitation reactions are used to make insoluble salts.hen solutions of two soluble salts are mixed, a solid may form. The solid is called a precipitate, and the reaction is called a precipitation reaction. In this experiment insoluble magnesium carbonate is precipitated which can be filtered, dried and collected.