Averages for Havana in August. The month of August can be unbearably hot in Havana. Visitors at this time of year are often there for one purpose and that is to swim in the incredibly warm waters of the Gulf of Mexico. As the midday heat descends upon the Cuban capital city, Havana, everyone heads to the water or inside to keep cool.
A compound can have properties different from its constituents,  as a new substance is formed when the constituents are chemically  combined.  The constituents of a compound can be separated only by  chemical methods.     Mixtures    Mixtures are impure substances.
Air is a homogeneous mixture, not a compound. The components of a mixture can be separated once they have been combined; a compound is a new substance formed by a reaction between components.