Chapter 1 Flashcards
What is chemistry the study of?
Matter and its processes
Chemistry is the study of the _________, _________, and properties of _______, the processes that ________ undergoes, and the _________ changes that accompany these processes.
Composition; structure; matter; matter; energy
What questions does chemistry deal with?
- What’s a material’s makeup?
- How does a material change when heated, cooled, or mixed with other materials and why does this behavior occur?
What are the branches of chemistry?
Organic, inorganic, physical, analytical, biochemical, and theoretical chemistry.
Organic chemistry
The study of most carbon-containing compounds
Inorganic chemistry
The study of non-organic substances, many of which have organic fragments bonded to metals (organometallics)
Physical chemistry
The study of the properties and changes of matter and their relation to energy
Analytical chemistry
The identification of the components and composition of materials
Biochemistry
The study of substances and processes occurring in living things
Theoretical chemistry
The use of mathematics and computers to understand the principles behind observed chemical behavior and to all design and predict the properties of new compunds
What is a chemical?
Any substance that has a definite composition in terms of atoms that compose it.
Why is basic research carried out?
For the sake of increasing knowledge, such as the how and why a specific reaction occurs and what the properties of a substance are
Why is applied research carried out?
To solve a problem
What are scientists driven by in applied research?
Desire to solve a specific problem
What does technological development typically involve?
The production and use of products that improve our quality of life.
True or False: Technological applications NEVER lag far behind the discoveries that are eventually used in technologies.
FALSE
Do basic research, applied research, and technological development often overlap?
Yes
What is mass?
Amount of matter in an object
What is matter?
Anything that has matter and takes up space
What is an atom?
The smallest unit of an element that maintains the chemical identity of that element
What is an element?
A pure substance that cannot be broken down into, simpler, stable substances and is made up of one type of atom.
What is a compound?
A substance that can be broken down into simple stable substances. Each compound is made from the atoms of two or more elements that are chemically bonded.
Molecule
The smallest unit of an element or compound that retains of all the properties of that element or compound
True or False: Whether it is an element or compound, it has characteristic properties.
True
A property may be a characteristic that defines…
An entire group of substances. That property can be used to classify an unknow substance.
Extensive properties
Depends on the amount of matter that is present: volume, mass,, and amount of energy
Intensive properties
Do not depend on the amount of matter present: boiling, melting point
What is a physical property?
A characteristic that can be observed or measured without changing the identity of the substance
What do we commonly use a physical property to describe?
A substance
Examples of physical properties
Boling point, melting point
What is a physical change?
A change in a substance that does not involve a change in the identity of the substance.
Examples of physical change
Cutting, grinding, melting, boiling
What is a change of state?
A physical change of substance from one state to another
Matter in the solid state…
- Has definite volume and shape
- Particles are parked together in relatively fixed positions.
- The particles are held close together by the strong attractive forces, between them, and only vibrate about fixed points.
Matter in the liquid
- Has definite volume but an indefinite shape.
- Liquid takes the shape of its container
- Particles in them are close together but can move past one another
- Particles are moving faster than in a solid
Matter in the gas…
- Has neither definite volume nor definite shape
- Particles move very fast
- Less attractive distances
Plasma is…
A high-temp. physical state of matter in which atoms lose most of their electrons, particles that make up atoms lose most of their electrons, particle that make up atoms
What is a chemical property?
Relates to a substance’s ability to undergo changes that transforms it into difference substances.
When is a chemical properties are easiest to see?
when substances react to form new substances
What is a chemical change/reaction?
A change un which one or more substances are converted into different substances
What are the reactants?
The substances that react in a chemical change
What are the products?
The substances that are formed by the chemical change
Chemicals reactions are normally written with…
Arrows (yield) and plus signs
When physical or chemical changes occur…
Energy is always involved.
Examples of forms of energy
Heat and light
What can matter be classified as?
Pure or mixture substance
Describe the composition of a pure substance
Its the same through and can me a compound or an element
Describe the composition of a mixture
Contain more than one substance; can vary in composition and properties from sample to sample
What is a mixture?
A blend of two or more kinds of matter, each of which retains its own identity and properties; parts are simply mixed together physically and can usually be separated; properties are a combination of its components
Homogeneous
Mixtures that are uniform in composition
Homogeneous are also called…
Solutions
Heterogeneous
Mixtures not uniforms throughout
Describe a pure substance
- Has a fixed composition; always homogeneous; every sample has same characteristic and same composition
Are pure substances either compounds or elements?
Yes
What are the vertical columns of the periodic table called?
Groups; families
What are the horizontal rows of elements in the periodic table?
Periods
Where do physical and chemical properties change somewhat regularly?
Across a period
Elements that are close to each other in the same period tend to…
Be more similar than elements that are farther apart
How can you recognize a metal?
By their shininess, metallic luster, malleability, and ductile
What is metal good for?
Conducting heat and electric
What is malleability?
Can be hammered or rolled into thin sheets
What is ductile?
Can be drawn into fine wire
Do metals have diverse properties?
Yes
Many nonmetals are _____ at room temp.
Gases
Nonmetal solids tend to be…
Brittle rather than malleable and ductile
A nonmetal conducts…
heat and electricity poorly
Facts about the Noble Gases
Generally unreactive; gases at room temp.
What is a metalloid?
An element that has some characteristicsof metals and some characterisitics of nonmetals
All metalloids are _______ at room temp.
Solid
Properties of metalloids
Less malleable than metals; not as brittle as nonmetals; some have metallic luster
Metalloids are ___________ of electricity.
semiconductors
