Reaction Rates
Atoms, ions, and molecules are continuously moving (kinetic energy) and colliding with each other. Significant collisions can break existing or make new bonds.
The speed (rate) of a chemical reaction depends on several factors. These include:
i. Concentration of Reactants: Increased concentration of reactants = increases the rate of reaction. The more particles present in a confined region, the greater the chance that they will collide.
ii. Temperature: Increased temperature (increases particles speed) = increased rate of reaction
iii. Activation Energy : (Inversely Proportional) The initial input of energy needed for a chemical reaction to occur.
**Increase AE = Decrease rate of reaction**
iv. Catalysts: substances (protein) that can speed up chemical reactions. **They do not become a part of the product (they are not altered) **
FYI Catalysts in the human body are called Enzymes and function by lowering the activation energy needed for a reaction and properly orienting the colliding molecules.
Compounds can be classified into 2 categories: inorganic & organic.
Inorganic Compounds
An inorganic compound is one that is simple in structure and, most importantly, does not contain the element Carbon. Two important categories of inorganic compounds are water, acids, bases and salts. Many compounds contain ionic bonds. Water: Water makes up about 60% of body mass, making it crucial for survival. Many substances dissolve readily in water to form solutions, which is why it is often called the “universal solvent”. When molecules of inorganic acids, bases, or salts dissolve in water, they separate into ions through a process called Ionization or Dissociation.
Components of a Solution
Solute : A substance (liquid, solid, or gas) that dissolves in a solvent.
Solvent : Is a substance (liquid or gas) that a solute dissolves into. (Usually water = universal)
Solution : The combination of solvent + solute.
Solubility : The degree to which a molecule is able to dissolve in a solvent.
Other substances can be described according to their ability to dissolve in water as follows:
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