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.
Bases v alkalis. Bases are substances that react with acids and neutralise them. They are usually metal oxides, metal hydroxides, metal carbonates or metal hydrogen carbonates. Many bases are insoluble-they do not dissolve in water.If a base does dissolve in water, we call it an alkali.Here are two examples: Copper oxide is a base because it will react with acids and neutralise them, but it is not an alkali because it does not dissolve in water. Sodium hydroxide is a base because it will react with acids and neutralise them.f a base does dissolve in water, we call it an alkali. Here are two examples: Copper oxide is a base because it will react with acids and neutralise them, but it is not an alkali because it does not dissolve in water. Sodium hydroxide is a base because it will react with acids and neutralise them.