| Questions | 5 |
| Topics | Biosphere, Periods, Phase Transition, Power, Solid |
The biosphere is the global ecological system integrating all living beings and their relationships. This includes their interactions with the lithosphere (the rigid outer part of the earth, consisting of the crust and upper mantle), hydrosphere (all surface water), and atmosphere (the envelope of gases surrounding the planet).
The rows of the Periodic Table are called periods and contain elements that have the same number of electron shells ordered from lower to higher atomic number.
A substance undergoes a phase transition when it moves from one state of matter to another, for example, when water freezes or boils.
Power is the rate at which work is performed or work per unit time: \(P = {w \over t}\) and is measured in watts (W).
An element in a solid state has atoms or molecules that are constricted and do not move freely. Solids maintain a constant volume and shape and exist at a lower temperature than liquids or gases.