Does technology always follow science? explain.

Always is a pretty absolute word and since nothing is impossible I would say no. However, usually for the most part technology does follow science.
If you want to develop a technology, you need to understand the physical principals behind it such as dynamics,material behavior, etc. this all requires knowledge physics and chemistry.

Physicists during the 1800's were studying the theory to magnetic and electric fields and their interactions way before they were devices to create/observe this phenomenon esp. according to their theory.

Spontaneity tell us the direction of the reaction, but not how fast it goes. gibbs free energy brings together enthalpy, entropy and temperature in one easy formula. g = h - ts. and, finally the sign of delta g is always negative for a spontaneous reaction.