Science Unit B 1-2 Flashcards
Lab safety (name 5)
always wear safety goggles, tie your hair back, wash hands after handling chemicals, report any safety concerns, no jewelry,
WHMIS symbols & names
Workplace Hazardous Materials Information System
exploding bomb - for explosive or reactivity hazards
Flame - fire hazards
flame over circle - oxidizing hazards
Gas cylinder - gas under pressure
Health Hazard - may cause health effects
Corrosion (person washing hands) corrosive damage
! - may cause less serious health effects or damage to ozone layer
Skull and Crossbones - cause death or toxicity
What does yellow, orange and red mean?
Yellow triangle - caution
Orange diamond - warning
Red Octagon - danger
Matter (what it is) and classifications of matter (pure substances: elements and
compounds; mixtures: mechanical mixtures, suspensions, colloids, solutions)
Anything that has a mass and occupies space,
What are pure substances: elements and
compounds
Pure substance: substance made of only one kind of matter, which has a unique set of properties.
Compound: chemical combination of 2 or more elements. (is a pure substance)
Element: A pure substance that cannot be broken down into other substances (substance made of one atom).
mixtures: mechanical mixtures, suspensions, colloids, solutions
suspension - a cloudy mixture in which tiny particles of one substance are held within another. (you can see the particles, ex italian dressing or sugar and water)
Colloid - A cloudy mixture where the particles of a suspended substance are so small they cannot be easily separated out of the substance (mixture where you cannot see particles and cannot be separated)(ex whipped cream, milk, jelly)
Mechanical mixture: a mixture with different parts that you can see (2 or more substances) (ex pizza, milk and cereal, soil, sand)
Solution: a type of homogeneous mixture that is made up of two or more substances (ex salt water, rubbing alcohol, and sugar dissolved in water.)
Physical vs chemical properties
Physical property - used to identify matter (color and lustre)
Chemical property - describes how a substance interacts with other substances like acids. The five chemical properties are:
1. Reaction with Acids
2. Ability to Burn
3. Reaction with Water
4. Behaviour in Air
5. Reaction to Heat
Physical vs chemical change
Physical Change - when a substance undergoes change and appearance is altered (change of state or dissolved)
Chemical Change - when 2 or more materials react and create new materials
Terms used to describe changes in state
Sublimation: the substance changes from a solid to a gas without going through the liquid phase.
Condensation : change from gas to liquid
Deposition : gas changing to solid
6000 B.C
Chemists investigated materials that were valuable such as gold and copper due to lustre (shinny), malleability (Malleability is a physical property of metals that defines their ability to be hammered, pressed, or rolled into thin sheets without breaking), ductility (the ability of a material to be drawn or plastically deformed without fracture.) and durability (the ability to withstand wear, pressure, or damage.) Copper was introduced.
400 B.C (Democritus)
Democritus described that the smallest particles that could not be broken further. stated that each type of material was made up of a different type of atomos.
350 B.C (Aristotle)
Aristotle, supported a different hypothesis that everything was made of earth, air, fire, and water.
1500 A.D (alchemists)
Alchemy Takes Over, experiments with matter were carried out by Alchemists. They were trying to turn common metals into gold
1597 A.D (Libau)
Andreas Libau made important chemical discoveries + first chem textbook
1660 A.D (Boyle)
Robert Boyle experimented with the behaviour of gases. Was convinced that matter was made up of tiny particles
1770 A.D – 1780 A.D (Lavoisier)
Lavoisier developed a system for naming chemicals.
Lavoisier is called the “father of modern chemistry.”
John Dalton
John Dalton suggested that matter was made up of elements. Dalton was the first to define an element as a pure substance that contained no other substances. stated that each element is composed of a particle called an atom. he developed a new set of symbols
for elements.
(developed atoms and elements and symbols for elements)
Thompson
first person to discover a subatomic particle (a particle smaller than an atom). concluded that the rays were
made up of streams of negatively charged particles. He named them electrons. (“raisin bun model”) Described the atom as a positively charged sphere in which negatively charged electrons were embedded like raisins in a bun.
(created raisin bun model, described atom)
Hantaro Nagaoka
refined the model of the atom further. In his model, the
atom resembled a miniature solar system
Ernest rutherford
predicted that all the high-speed particles would pass straight through the foil without being affected by the gold atoms. Suggested that the atom was mostly empty space with nucleus.
Alchemists
Discovered plaster of Paris for use in casts to help bones heal. A group that practiced with metals.
Bohr and Bohr model (go look at notes for model)
Bohr said that they move in specific circular orbits, or electron shells
James Chadwick
discovered that the nucleus contained positively charged particles called protons, and neutral particles called neutrons.
Jöns Jacob Berzelius
Berzelius suggested using letters rather than pictures to
represent each element. The first letter (capitalized) of an element would become the symbol.
Arrangement of periodic table
Blue and purple colored elements in this area are metals. Metals are shiny, malleable, and ductile.
Green area are non-metals. Non-metals can be a solid or a gas. Solid nonmetals are dull, brittle elements.
diagonal orange elements called metalloids. Metalloids have both metallic and non-metallic properties.
From left to right , the elements change from metals to nonmetals.
most reactive metals start on the left and move right, the metals generally become less reactive.
alkali metals; alkaline earth metals; metalloids; halogens; noble gases; metals and non-metals
alkali metals- Group 1 elements, (not including H), called the alkali metals (most reactive of the metals.)
They react when exposed to air or water. they’re on the very left, first column
alkaline earth metals- They react when exposed to air and water as well, but not as reactive as alkali metals. (they’re the second column on the very left in blue.
halogens- They are the most reactive non-metals. For example, fluorine can etch glass, chlorine is common. (they’re group 17)
Group 18 elements are the noble gases—Very Stable
metalloids- the line splitting purple and green
metals and non-metals- metals are purple to left, non metals are the green
Periods vs Groups/Families
group- Each vertical column forms a group, or family, of elements (numbered from 1 to 18). These groups have similar chemical properties.
Period- Each Horizontal Row is called a period. There are 7
Protons, Electrons and Neutrons (what are they, charges, where they are found, etc)
Atoms are neutral, the number of protons equals the number of electrons.
Protons- positively charged particle in the nucleus of an atom
Electrons- negatively charged particle that orbits the nucleus of an atom
Neutrons- neutral particle in the nucleus of an atom.
The neutron has about the same mass as the proton but carries no electrical charge.
Atomic number, atomic mass
Atomic number- shows how many protons are in the nucleus of one atom of the element
Atomic mass- The number below the element’s name is the atomic mass. The atomic mass tells you the total mass of all the protons and neutrons in an atom.
Atomic number = number of protons = number of electron # of neutrons = atomic mass – number of protons
hh
metals are.. non-metals are…
metals- shiny, ductile, malleable and heat conductors.
non-metals- dull, brittle, insulators
(metalloid - silicon, Metal - copper, noble gas- …, halogen-…)
