Two chemical reactions are shown:

ca(oh)2 → cao + h2o
4k + o2 → 2k2o

which statement is true?

a. both are synthesis reactions.

b. both are decomposition reactions.

c. a is a synthesis reaction, and b is a decomposition reaction.

d. a is a decomposition reaction, and b is a synthesis reaction.

Option D, A is a decomposition reaction and B is a synthesis reaction.

Essentially, a decomposition reaction means that molecules split and form new molecules. In this case, Ca(OH)2 would decompose into CaO and H2O.

As you can guess, synthesis reactions means that molecules combine together. In this case, 4K + O2 reacts together and combines, becoming 2K2O.

-T.B.

C) electrons encircling a nucleus with neutrons and protons