Chemistry Chapter 1 & 2
groups (PERIODIC TABLE)
-vertical columns -elements in groups have similar chemical & physical properties
indications that a chemical change has occurred
. Smoke/ production of gas/ temperature change 2. Color change 3. Odor 4. Energy change (endothermic/ exothermic) 5. Can't get back what you started with
8 central themes of chemistry
1)Chemistry as the central science: chemistry is used in other sciences 2)Electrons and the structure of atoms 3)Bonding and interactions: chemical compounds and bonds 4)Reactions: Chemical reactions 5)Kinetic theory: particles in matter are in constant motion 6)The mole and quantifying matter: measurements 7)Matter and energy: Heat during chemical reactions 8)Carbon chemistry: 10 million carbon containing compounds
3 reasons to study chemistry
3 reasons to study chemistry 1)Explaining the natural world: figure out how things work. Ex. why does bread go bad so fast. 2)Preparing for a career: a lot of jobs require chemistry. Ex. creating a new toothpaste, firefighter 3)Being an informed citizen: where money should go. Ex. cancer research
Heterogeneous mixture
Heterogeneous mixture not uniform throughout. You can see various components (chicken noodle soup)
Two types of mixtures
Homogeneous and heterogeneous
Inorganic chemistry
Inorganic chemistry study of chemicals that do not contain carbon, mostly rocks, minerals, metals (mainly non living things)
5 traditional areas of study
Organic chemistry, Inorganic chemistry, Analytical chemistry, Biochemistry, Physical chemistry
3 states of matter
Solid, liquid, and gas
What contributions did alchemists make to science?
alchemists wanted to change metal into gold; developed techniques & laboratory equipment; did not provide logical explanations for their work
matter
anything that has mass and takes up space (volume). Liquid, solid, and gas. Example: a desk. Example of something that is not considered : heat, sound, sunlight
chemical change examples
burning, rotting, rusting, decomposing
irreversible physical change
cannot return to original state
chemical change
change that produces matter with a different composition than the original matter
reversible physical change
changes back
alchemy
chemistry based on the transformation of matter;chemical science aiming to change metals into gold
Applied Chemistry
chemistry directed at solving a problem or goal
examples of intensive properties
color, odor, luster, density, malleability, conductivity, hardness, boiling/melting/freezing point
Analytical chemistry
composition and measurement of matter. (what something is made of)
physical property
condition of a substance that can be measured without changing its chemical composition. (Color, malleability, conductivity, boiling/ melting points, state of matter (Solid, liquid, gas)
How did Lavoisier transform chemistry?
created the scientific method which was a logical, systematic approach to problem solving
Independent variable
the variable that you can change during an experiment 2 (manipulated variable)
controlled variable
variable that stays constant throughout the entire experiment & that you cannot change
Homogeneous
(aka SOLUTION) uniform throughout. You cannot see various components. (gatorade
What is the difference between a vapor and a gas?
***vapor - describes gaseous state of a substance that is generally liquid or solid at room temperature (water vapor) ***gas - substances that exist in a gaseous state at room temperature (oxygen)
physical change examples
---freezing, boiling, condensing, ---tearing, breaking, cutting, shredding
differences between conventional plastics and bioplastics
---plastics are made by bonding together monomers through a reaction called polymerization ---bioplastics are made by converting the sugar from plants into plastic
compound
-2 or more elements that are Chemically combined in a fixed ratio. -cannot be separated by physical means
5 techniques to separate mixtures
-Filtration (solids), -magnetism (metals), -Distillation (separates based on boiling points (most complex), -Centrifuge (density)- (spin in circle), -Evaporation
mixture
-a physical blend of 2 or more substances -Can be separated by physical means -Variable composition.
periods (PERIODIC TABLE)
-horizontal rows -elements have nothing in common
element
-in its simplest form of matter that retains its own set of physical / chemical properties -cannot be broken down into simpler substances.
chemical formula
-tells us what elements we have -number of atoms of each element
alloy
homogeneous mixture of 2 or more metals (BRASS, STEEL)
law of conservation of mass
in any physical or chemical reaction, mass is consevred
Explain why all samples of a substance have the same intensive properties.
intensive properties are primarily the physical properties of a substance; properties that stay with a substance no matter what
examples of extensive porperties
mass, weight, volume, length
What always happens during a chemical change?
matter is produced that has different chemical composition that the original matter
substance
matter that has to have a uniform and definite composition.
Scientific method
observation, hypothesis, test hypothesis, theory, and scientific law
Biochemistry
processes that takes place in living organism (digestion, muscle contraction, biomolecules)
Intensive properties
properties that depend on the type of matter in a sample, not the amount.
Pure chemistry
pursuit of knowledge for one's own sake
Physical change
some properties of a material might change but its chemical composition will remain the same.
Physical chemistry
studies, rates, and mechanisms of chemical reactions (energy transfer)
Organic Chemistry
study of carbon containing compounds. (development of plastics, pesticides, medicines)
precipitate
substance that forms when you add 2 liquids together; will form a solid
What is technology? How is it related to chemistry? Give examples of technology that is related to chemistry.
technology is the means by which society provides its members with those things needed and desired to accomplish tasks, making them easier, quicker & possible; ---examples of technology related to chemistry: lab equipment new medicines conservation/production of energy
chemistry
the study and composition of matter and the changes that matter undergoes
dependant variable
the variable that is observed during an experiment (responding variable)