Answer:
Explanation:
A single replacement or single displacement reaction is a reaction in which one substance replaces another.
A + BC → AC + B
The replacement of an ion in solution by a metal higher in the activity series is a special example of this reaction type.
The relative positions of the elements in the activity series provides the driving force for single displacement reactions.
A double replacement reaction is one in which there is an actual exchange of partners between reacting species. This reaction is more common between ionic substances;
AB + CD → AC + BD
Such reactions are usually driven by;
- formation of precipitation
- formation of water and a gaseous product
<h3><u>Answer;</u></h3>
When hydrogen is covalently bonded to an electronegative atom
<h3><u>Explanation;</u></h3>
- Hydrogen bonding is a special type of dipole-dipole attraction between molecules. It results from the attractive force between a hydrogen atom covalently bonded to a very electronegative atom such as a N, O, or F atom.
- Highly electronegative atoms attract shared electrons more strongly than hydrogen does, resulting in a slight positive charge on the hydrogen atom. The slightly positive hydrogen atom is then attracted to another electronegative atom, forming a hydrogen bond.
