Explanation:
A single-replcaement reaction is a chemical reaction in which one element replaces another in a compound.
A double replacement reaction is a reaction in which the metals in two ionic compounds exchange partners.
The answer is A) Water has surface tension.
This is the correct answer because water allows animals and really light items to rest upon the top of the water.
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Answer:
A. They must be kept separate from moisture and oxygen
Explanation:
Alkali metals refers to a group of chemical elements in the periodic table. It is the common name given to Group 1 elements (excluding hydrogen). They are generally metallic in nature with physical properties like shining lustre, silvery in appearance etc. Alkali metals include lithium, Pottasium, Sodium, Rubidium etc.
One important chemical property of alkali metals is their high reactivity i.e. they tend to react quickly with other substances. For example, alkali metals react vigorously with water to form hydroxides. They also react with oxygen to form oxides. Due to this highly reactive properties, they are kept or stored away from moisture (water) and oxygen (present in air).
