Chemisty of Life - Basics Flashcards
What are Elements?
Single substance that can not be broken down into smaller substances
What is an Atom?
Smallest particle of an element that still has all of the proerties of that element
Symbol
The letter or letters representing an element
What is a compound
The chemical combination of two or more elements
What is a molecule?
A small part of a compound, which still has all of the properties of that compound
What are Organic Compounds
Always contain Carbon - especially in C-C (Carbon- Carbon bond) and C-H (Carbon Hydrogen bond) assiciated in living things and their products for example carbohydrates, proteins, fats and nuleic acids
What are Inorganic Compounds
Lack Carbon. When Carbon is present is usually is combined with Oxygen for example Carbon Dioxide, inorganic acids, saltes, water and bases
What are Chemical Bonds
Hold the atoms in a molecule together. In general the more chemial bonds a molecule has the more energ it contains
What is a Convalent Bond
A chemical bond that involves the sharing of electron pairs between atoms.
What is a Valence Electron
A valence electron is an outer shell electron that is associated with an atom and can participate in formation of a chemical bond if outer shell is not closed
Name three types of Compound Forulae
Structural Formula - indicates kind of atoms in a molecule, their proportion and how atoms are arranged or held together
Molecular Formula - Actual numbers and kind of atoms in a molecule - Does not indicate structural setup
Emperical Formula - Shows the symbols of the elements in a compound followed by small subscript numbers indicating the ration of atoms within the compound
What are Acids?
Substances, which ionize into positively, charged hydrogen ions in a water solution (H+ions)
For example: HCI — H + + Cl
Acids turn litmus paper blue - and generally have a sour taste
What are Bases
Ionize into negatively charged hydroxide ions in a water solution (OH_)
For example: KOH — K + + OH- (Potassium Hydroxide – Potassium + + Hydroxide)
Bases turn litmus paper blue - and generally feel slippery to touch and taste bitter
What is a Neutralisation Reaction
Important in living things
when an acid and a base react to form water and a salt and involves the combination of H+ ions and OH- ions to generate water
For example HCI + NaOH — NaCl + HOH - this is how stomach acids work (hydrogen Cloride + Sodium Hydroxide — Sodium Chloride+ Hydrogen Hydroxide
What is the pH Scale
Measures degree of substance alkalinity or acidity (alkaline = base)
Most bodily fluids have a neutral pH level (6-8)
