# Science Unit Test

version from 2016-10-27 02:48

## Section 1

Define the term matterMatter is everything around us. Atoms and molecules are composed of matter. Matter is anything that has mass and takes up space.
3 States of matterSoild, liquid and gas
Particle theoryAll matter is made up of tiny particles, All particles of one substance are the same, Different substances are made of different particles, Particles are always moving the more energy the faster they move, There are attractiuve forces between particles.
How does each state of matter differSoild: Speed is very slow, Attraction is very strong, Space between particles are very close, Liquid: Space between partcles are close, Attraction is stong and speed is slow, Gas: space between particles are far apart, Attraction is very weak and speed is very fast
Changing of the statesMelting: Solid ot liquid, Freezing: Liquid to soild, Evaporation: Liquid to gas, Condensation: Gas to liquid, Sublimation 1: Solid to gas, Sublimation 2: Gas to solid
Difference between physical and chemical propertiesPP: Observed with 5 senses, determined without destroying matter, gives us information about what the substance is like. CP: Changes into new substance, Flammabal, Reactive to acid, heat and light
What is qualitative and quantitativeQualitative: Can be observed with the 5 senses, has no numerical value, can be described with lustre, ductility and malleabilty. Quantitative: Measured(density oand/or solubility, has a numerical value
What is the term densityMeasure of how much mass is contained in a given unit volume of a sustance
Calculate densityDividing the mass of a smaple by its volume
Calucate mass and volumeMass is volume times the density and volume is mass divieded by density
The units for d,m,vD: g/cm or kg/m3, M: g or kg, V: cm3 or m3 or mL
What is grassG:givens, R:Required,A:analysis, S: Substitution, S: Solution
What is the density towerTells us the density of substances in layers
Physical properties characteristic:Helps us identify and classify substances. Substance is always the same. Examples: Freezing/melting, boiling/condesing point, density, magnetism and solubility
What is unusual behaviour of waterWhen water freezes the molecules spread apart and beocmes less dense. Water expands when frozen and floats. Salt lowers the freezing pint and water will stay at a liquid until 16C
Physical and chemical changePC:Change in size, shape or state, no new substance is created, CC: Change in physical and chemical properties, new substance is formed.
5 clues of a chemical changeChange in colour, a solid forms of hen mixong two substances, gas forms bubbles and /or odour, change is irreversible and change in temp. or light
What is a pure substanceMade up of only one type of particle.
What is a mixtureContains more than one type of particle
mechanical MixtureDifferent particles that are visible
SolutionDifferent particles present, but cannot see them.
Physical and chemical properties of metalShiny, dense and conducts heat and energy, most likey to lose electrons in a chemical reaction
Non-metalNot dense, dull, poor conducters of heat and energy, most likey to gain electrons in a chemcial reaction
MetalloidsHave both proerties of mteal and non-metals
Groups and periods18 groups and 7 peroids
Name the groups1: Alkali metals, 2: Alkaline earth metals, 17: Halogens and 18; noble gases
What does the chemical formula tell usTells us the number of atoms of the element in a compund.
JJ ThomsonThought the atom was a solid with postitve and negative charges spread(plum pudding)
Niels BhorElectrons orbited around the nucleus in specific energy shells(bhor-rutherford diagram)
John DaltonBelieved in indivisible atoms( billard board model)
Ernest RutherfordThe gold foil experiemnt
Subatomic particlesProtons:+ mass is 1 and in nucleus, electron - mass is one and orbiting around nucleus and neutron 0 mass is 0 and in nucleus
How do u write an element in standard notationIncludes element name, mass, atomic number and ion
Bohr-rutherford diagram keysinclude proton and neutron in nucleus and electron orbiting
Ion rutherford diagramTo add or subtract to the elecron. Do the opposite of the symbol
What is valencethe outer electron shell
what is valence electronsoccupy the valence shell
what is moecular compoundsHave more than one type of element
What is molecular elementA pure substance Hofbrwinkle
what bond does a molecular compound forma convalent bond
Why do ionic compounds formto form a formation of postive and negatives
what elements make up ionic compoundsElemnet in the same family
what is a anionNegatively charged ion when a neutral atom gains a electron
What is a cationpositively charged ion when a neutral atom loses an electron
How to name a ionic compoundCa2+
ionic compound forms what bondA chemical bond between a metal and non-metal
What is electrolysiss of waterexample of a chemical change.Electrical energy used to break water molecules apart.
What does it dousing electrial currents to break compounds into a element
How can we prove this the gas test in class for hydrogen, oxygen and carbon dioxide gas. ( what happend)
What is DDTA compound of carbon, hydrogen and chlorine
Impacts with DDTlinked to human cancer if lots of exposure. Powerful insecticide. Reduced infections
What do we use DDT forA fat soluble, inside fatty tissure
Where is it useddoes not mix well with water but dissolves in oil and fats. stored in body fat. used in pesticide