Chemistry Questions

Lord Kelvin, working in Scotland, developed the Kelvin scale in 1848. His scale uses molecular energy to define the extremes of hot and cold. Absolute zero, or 0 K, corresponds to the point at which molecular energy is at a minimum. The Kelvin scale is preferred in scientific work, although the Celsius scale is also commonly used. Temperatures measured on the Kelvin scale are reported simply as K, not °K.

T (in °C) + 273.15 = T (in K)

T (in K) − 273.15 = T (in °C)

The temperature at which a substance can exist in equilibrium in the liquid, solid, and gaseous states. The triple point of pure water is at 0.01°C (273.16K, 32.01°F).

Ionisation energy is the energy required to remove one mole of electrons from one mole of gaseous atoms. Atoms are more stable when they have full valence shells.

The ionization energy decreases from top to bottom in groups, and increases from left to right across a period.

HGence, in this trend Francium (Fr) has the lowest ionization energy.