science term 2 test Flashcards
(24 cards)
What does the periodic table represent?
The periodic table represents the organization of chemical elements based on their atomic number, electron configuration, and recurring chemical properties.
It provides a framework for understanding the relationships between different elements.
How can you find element symbols using the Periodic Table?
You can find element symbols by locating the elements on the Periodic Table, which lists each element’s symbol alongside its atomic number and name.
This allows for easy identification and reference.
Define an element.
An element is a pure substance that cannot be broken down into simpler substances by chemical means.
Elements consist of atoms that have the same number of protons.
List properties of metals.
- Shiny
- Malleable
- Ductile
Metals tend to have high thermal and electrical conductivity as well.
What does it mean if a material is malleable?
It means the material can be hammered flat without breaking.
Malleability is a common property of metals.
What does it mean if a material is ductile?
It means the material can be twisted into wires.
Ductility is another characteristic commonly associated with metals.
Describe the arrangement of atoms in elements.
Atoms in elements are arranged in a specific pattern based on their atomic structure, which determines the element’s properties.
This arrangement influences how elements interact with each other.
Define an atom.
An atom is the smallest unit of an element, consisting of protons, neutrons, and electrons.
Atoms are the building blocks of matter.
Define a molecule.
A molecule is a group of two or more atoms bonded together.
Molecules can consist of the same or different elements.
Define a compound.
A compound is a substance formed when two or more different elements are chemically bonded together.
Compounds have unique properties different from the individual elements.
Define a mixture.
A mixture is a combination of two or more substances that are not chemically bonded.
Mixtures can be separated by physical means.
Give examples of molecules.
- O2 (oxygen)
- H2O (water)
- CO2 (carbon dioxide)
These are all examples where atoms are chemically bonded.
What is the chemical formula for water?
H2O
This formula indicates that each molecule of water consists of two hydrogen atoms and one oxygen atom.
What is the difference between chemical and physical changes?
Chemical changes result in the formation of new substances, while physical changes do not.
An example of a chemical change is rusting, while melting ice is a physical change.
Provide an example of a physical change.
Change of state (e.g., ice melting to water).
The substance remains the same during a physical change.
Provide an example of a chemical reaction.
Color change (e.g., iron rusting).
Chemical reactions often involve changes in energy and the formation of new substances.
What are reactants and products in a chemical reaction?
Reactants are the starting substances, and products are the substances formed as a result of the reaction.
This relationship illustrates the conservation of mass.
What factors can speed up the rate of chemical reactions?
- Particle size
- Temperature
- Concentration
- Catalyst
These factors influence the frequency and energy of collisions between reactant particles.
What is the collision theory?
The collision theory states that for a reaction to occur, particles must collide with sufficient energy and the correct orientation.
This theory helps explain reaction rates.
What is an independent variable in a research scenario?
The independent variable is the factor that is deliberately changed or manipulated in an experiment.
This variable is tested to observe its effect on the dependent variable.
What is a dependent variable?
The dependent variable is the factor that is measured or observed in an experiment.
It is affected by changes in the independent variable.
What is a controlled variable?
A controlled variable is a factor that is kept constant to ensure a fair test.
Controlling variables is crucial for reliable experimental results.
How do you represent results and data?
Results and data can be represented using graphs, tables, and charts.
Proper representation helps in analyzing and interpreting data effectively.
What is the purpose of drawing a conclusion in an experiment?
The purpose is to summarize the findings and determine whether the hypothesis was supported or refuted.
Conclusions help in understanding the implications of the results.
