Answer:
Explanation:
i. From solid to liquid (melting)
For melting to occur, heat must be absorbed by the substance being melted. When the substance gains significant amount of heat, its particles begins to vibrate and move on top of one another.
ii. From liquid to solid (freezing or hardening)
In this phase change, heat is removed from the system. This allows for the molecules to lose their kinetic energies and form an ordered arrangement from their liquid or molten state.
iii. From liquid to gas (evaporation)
As randomness continues to increase, more heat is absorbed to break the attractive forces between molecules of liquids. Phase change from liquid to gas is a heat absorbing process.
iv. From gas to liquid (condensation)
In condensation, heat is lost by a substance. To condense or collect gas particles together, heat must be removed from the system. This allows for a diminished kinetic energy among the particles of the system.
Answer:
4. c) Lose only 3 electrons
5. d) Nitrogen.
Your answers are correct
The balanced equation that describes the reaction between hydrogen and oxygen to produce water is 2 H2+O2= 2H2O. Hence to produce 2 moles of water 2 moles of hydrogen is equivalently needed. For the given, 0.253 moles water thus needs 0.253 moles of hydrogen, too.
Answer:
3
Explanation:
You need to remember that to measure the number of unparied electrons in an atom you need to undestard its electron configuration, and the electron configuration of phosphorus is 1s2 2s2 2p6 3s2 3p3, just the last state "3p3" have unpaired electron, and because a p state can fits 6 electrons, and here are only 3, that means that those 3 are unpaired.
Mantle convention, convection cells in the mantle, and produces horizontal motion of mantle material close to the Earth surface.