Chemistry Terms

Chemistry Terms

1. Properties

   • Chemical
     • Definition: a characteristic of a substance that is determined when the composition of the substance is change and one or more new substances is created
       • Examples~ flammable, heat combustion, toxicity
   • Physical
     • Definition: a characteristic that can be determined without changing the composition of the substance
       • Examples~ it's state, colour, size, density
     • Characteristic Physical
       • Definition: a physical property that is unique to a substance and can be used to identify the substance
         • Examples~ density, melting point, freezing point, boiling point

2. Changes

   • Physical
     • Definition: a change in which the composition of the substance remains unaltered and no new substances are produced
       • Examples~ ice cube> water, light switch> on> off, freezing> boiling> melting
   • Chemical
     • Definition: a change in the starting substance and the production of one or more new substances
       • Examples~ fire works: change of colour, change of odour, bubbles are visible, a new solid is seen, precipitate, change in temperature or lighting

3. Collecting Data

   • Quantitative
     • Definition: Numerical Data
       • Examples~ lusture (shine), optical clarity (transparent), viscosity (thickness), hardness, dull, brittleness (how easily something breaks), Malleability (easily you can shape it), Electrical Conductivity (how fast energy flows), Ductility (how easy it stretches)
   • Qualatative
     • Definition: 5 senses when collecting data (not numerical)
       • Examples~ colour, taste, texture, odour, shape

4. Matter

   • Mixtures
     • Definition: combination of 2 or more pure substances (particles)
       • Examples~ orange juice, M&M's, coffee, party mix
   • Pure Substance
     • Definition: a substance that is made up of only one particle
       • Examples~ water, 24 kt gold, carbon dioxide
   • Mechanical Mixture
     • Definition: a mixture in which you can distinguish between different types of matter
       • Examples~ lucky charms, a classroom, cigarette, fruit salad
   • Solution
     • Definition: a uniform mixture of 2 or more substances
       • Examples~ koolaid, apple juice, tea, gatorade
   • Alloy
     • Definition: a solid solution of 2 or more metals
       • Examples~ 12 or 18 kt gold, rims of a car tire
   • Particle Theory
     • Definition: a theory that describes the composition and behaviour of matter
       • SOLID, LIQUID, GAS
   • Chemical Formula
     • Definition: a notation that indicates the type and number of atoms in a pure substance
       • Example~

5. Molecules

   • Definition: 2 or more atoms of the same or different elements that are chemically joined together in a unit
     • Examples~ water, oxygen, gas, carbon
   • Molecular Element
     • Definition: a molecule consisting of atoms of the same element
   • Molecular Compound
     • Definition: a molecule that consists of 2 or more different elements
       • Examples~ AlCl3, NaCl

6. Periodic Table of Elements

   • Atomic Number
     • Definition: number of protons in an atom
       • Examples~ Nitrogen> 7, Oxygen> 8, Sodium>11
   • Atomic Units
     • Definition: the way to measure protons within an element
       • Example~ 1u = 1 proton
   • Definition: a table of chemical elements arranged in a specific order of atomic number and reactivity levels
     • Example~ The Periodic Table of Elements
   • Mass Number
     • Definition: number of protons and the number of neutrons
       • Examples~ oxygen> 16, sodium> 23
   • Atomic Mass
     • Definition: average of all the different mass numbers possible for an atom
       • Example~ Rubidium> 85u/86u = 85.5

7. Ions

   • Definition: a particle that has either a positive or negative charge
     • Examples~ Na+ and H+
   • Cation
     • Definition: a positively charged ion
       • Examples~ Cu2+ and Fe3+
   • Anion
     • Definition~ a negatively charged ion
       • Examples~ NO3- and Cl-
   • Ionic Compound
     • Definition: a compound that consists of positively and negatively charged ions
       • Examples~ NaCl, Mg(NO3)2, KF, FrBR
   • Isotope
     • Definition: an atom with the same number of protons but a different number of neutrons
       • Example~ Carbon-12 > 6 protons and 6 neutrons

8. Density

   • Definition: how much mass is contained in a given volume of substance
     • Examples~ less dense = larger spaces and lighter particles, more dense = closely packed and heavy particles,
       • Examples~ Pure Water= 1g/ml, Lead= 11.36g/ml, Gold= 19.32g/ml

Imagens e arquivos do mapa