What is the condensed formula for 2-pentyne??

C5H8

Explanation:

The condensed formula is also known as structural formula of a chemical compound which shows a graphical representation of the molecular structure that represents, the arrangement of the atoms in the three-dimensional space.

The condensed formula of  2-pentyne is C5H8.

There is a triple bond between two carbon atoms at second carbon as shown in the figure.

Water is a compound because it is made up of water molecules. There is no such thing as water atoms. Water molecules are made of hydrogen and oxygen atoms, in the definite proportion of two hydrogens for one oxygen. Hope this helps!