In a double-replacement reaction, there are two reactants and product(s

Two

Explanation:

In a double-replacement reaction, there will be two reactants and two products.

It is called double replacement reaction because one element in reactant 1 replaces an element in reactant 2 and other element in reactant 2 replaces other element in reactant 1.

Here two replacements are taking place. Hence, this is called double replacement reaction.

A Neutralization reaction i.e an Acid - Base reaction is a good example of Double replacement reaction.

An Example is provided below for better understanding :

HNO3 + NaOH --> NaNO₃ + H₂O.

Here HNO₃ is the acid and NaOH is the base which are the reactants.

NaNO₃ and H₂O are the products.

This is a double replacement reaction because,

Hydrogen(H) in  HNO₃ replaces Sodium(Na) in NaOH, and

NO₃ in HNO₃ replaces OH in NaOH.

Here, there are 2 reactants and 2 products.

answer

fusion: the energy source of stars. the energy released from the collapse of the gas into a protostar causes the center of the protostar to become extremely hot. when the core is hot enough, nuclear fusion commences. fusion is the process where two hydrogen atoms combine to form a helium atom, releasing energy.

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