Geometry and bond angle of SiCl4​

What does a particular point on a line of a phase diagram represent? o a. the maximum temperature a substance can exist at without bonds breaking b. the pressure created by the kinetic energy of molecules at a particular temperature c. the melting point or boiling point of a substance at a specific pressure d. the conditions in which temperature and pressure have equal effects on a substance

Which element would mostly likely have an electron affinity measuring closest to zero

Avariable that is not being directly tested during an experiment should be changed varied experimented controlled