Basic Chemistry - Atoms, Ions, and Chemical Bonds Flashcards
What are atoms made of?
- Atomic nucleus containing neutrons (no electrical charge) and protons (1 positive charge)
- Electron cloud containing electrons (1 negative charge)
What is the simplest atom?
Hydrogen which contains one proton and one electron
What is electrostatic force?
Particles of opposite charge are attracted to each other
Particles of the same charge are repulsed by each other
What are valence electrons?
The electrons in the most outer part of the atomic shell. and will participate in chemical reactions
What happens if an atom gives away an electron?
It loses negative charge and therefore becomes more positive
What happens if an atom gains an electron
It gains more negative charge and therefore becomes more negative. Becoming more negative can also be described as reducing charge.
Reduction means gaining an electron
What are oxidation reactions?
O I L - Oxidation is loss of an electron by a substance
What are reduction reactions?
R I G - Reduction is gaining of an electron by a substance
What happens when an atom gains or loses one or more valence electrons?
Becomes an ion
Positively charged ion - CATION
Negatively charged ion - ANION
What are ions in the body referred to as?
Electrolytes, which are important for transmitting electrical signals
Why are ions important in the body?
Electrical signalling, enzyme activity, regulating fluid balance, bone and teeth structure
What are some common ions in the body?
Sodium Na+
Chloride Cl-
Calcium CA2+
Potassium K+
What is an ionic bond?
Once an oxidation/reduction reaction occurs, there will be two oppositely charged ions
Oppositely charged ions will be attracted to each other
Attraction holds ions together to form a molecule
Next strongest bond
What is covalent bonding?
The sharing of electrons - strongest bond
Non-polar molecules
The electrons are shared evenly
Polar molecules
Electrons not shared evenly
Uneven sharing of electrons
Causes partial charge differences across the surface of the molecule.
Some parts postive
Some parts negative
What is hydrogen bonding?
Partial charge differences across the surface of the molecules make them attracted to the opposite charge, or opposite partial charge, of other ions or molecules
Weakest bond
What is metabolism?
All of the chemical reactions that in the body
Some factors can increase the rate of metabolism - thyroid hormone
How is energy related to chemical reactions?
- Formation of chemical bonds requires energy
- Chemical bonds store energy
- When chemical bonds break energy is released some of which is lost in the form of heat
What is ATP?
Adenosine triphosphate which is often used to provide energy within cells
What is activation energy?
The initial energy required to initiate a chemical reaction
breaking of bonds - chemical reaction releasing energy
Formation of bonds - chemical reaction taking up and storing energy
What are enzymes?
- Enzymes are proteins which make chemical reactions more likely to occur
- Lower the activation energy required to initiate chemical reactions
- increase rate of chemical reactions
- Thousands of different enzymes in the body with each regulating a particular chemical reaction
- Enzymes control metabolism
