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Short definition for this few words
polar covalent bonds
write a really short definition for each word in English, these are Biology words...
- ?Lv 61 十年前最愛解答
Ionic bond is the bonding which is formed between the ions. The ions held together by electrostatic force. E.g. the bond in NaCl.
Covalent bond is the boning intereaction achieved by sharing electrons between atoms as a result of formation of octet structure in the electronic configuration. E.g. The bonding in Chlorine molecule.
Polar covalent bond is similar to covalent bond but the electron pair is donated from one atom to another one with an empty orbital. E.g. one of the oxygen in nitrate salt.
Hydrogen bond is a kind of intermolecular bonding in which the hydrogen is bonded to atoms with high electronegativity such as oxygen or nitrogen. The hydrogen therefore bears a higher positive charge which is attracted by the electronegative atom and form the hydrogen bond. E.g. The intermolecular bond in water.
pH scale is the range of the pH which measure the acidity of the substance. USually it is ranged from 1 -14. The lower the pH, the more the acidity.
pH is the short form of power of Hydrogen. It is defined as -log[H+]. The lower the reading, the more the acidity.
Acid is defined as the substance which bears hydrogen ions. (E.g. hydrochloric acid)
Base is the substance which can absrorb the hydrogen ion. (E.g. sodium hydroxide)
Neutral means the pH value is 7 and the substance is neither acidic nor alkali.
Hydrophobic means the substance dislikes water. (E.g. Oil)
Hydrophilic means the substance likes water. (E.g. Ethanol)
Suspension means the substance is not really dissolve in the solution but it is just finely distributing all over the solution. It still remains in its original state. (E.g. pepper powder in water)
Solution is a liquid which is mixed by two or more substance homogeneously. (E.g. Sugar water)
Solute is the substance which is defined to be dissolved. Usually its quantity in the solution is smller. (E.g. sugar in the sugar water.)
Solvent is the substance which is defined as the bulk substance to dissolve the solute. (E.g. Water in the sugar water.)
Adhesion is the attractive force between one substance to another substance. (E.g. Water to the glass).
Cohesion is the attractive force within the substance itself. ( E.g. The metallic bonding in mercury).