In two or more complete sentences, compare combination reactions to decomposition reactions.

Explanation:

When in a chemical reaction either two or more number of elements or compounds combine together to result in the formation of a single compound then they are known as combination reactions.

For example,

On the other hand, when in a chemical reaction a single compound is able to produce two or more number of products then its is known as a decomposition reaction.

For example,

the term hydride is commonly named after binary compounds that hydrogen forms with other elements of the periodic table. hydride compounds in general form with almost any element, except a few noble gases. the trends and properties vary according to the type of intermolecular force that bonds the elements together, the temperature, its molecular masses, and other components. hydrides are classified into three major groups, depending on what elements the hydrogen bonds to. the three major groups are covalent, ionic, and metallic hydrides. formally, hydride is known as the negative ion of a hydrogen, h-, also called a hydride ion. because of this negative charge, hydrides have reducing, or basic properties. its special characteristics will be further discussed.

explanation: