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Science Quiz 2
When do changes of state occur?
they happen when matter transforms from one state to another
What is an example of changes of state?
liquid (water) to solid (ice)
What are the transformation states of matter?
evaporation
condensition
freezing
melting
deposition
sublimation
Tempurature is measure of what?
the average KMT of particles in a substance
What does it mean to particles of the matter when the temp is increasing?
means they are agianing energy.
What happens when the matter reaches a certain temp?
the particles gain enough energy to change state.
What is diffusion?
is the movement of particles from an area to a high concertration to low concentration.
What do solids, liquids, and gases do?
they expand when heated, and contract when cooled.
What is thermal expansion?
the increase in volume of a substance when its temp increases.
What does heating do to particles?
increases kinetic energy
What is thermal conctraction?
the decrease in volume of a substance when its temp is lowered.
What does cooling do to particles?
decreases kinetic energy
Who were the 4 people who helped with the development of the atomic theory?
John Dalton, Jj Thompson, Ernest Rutherford, Neils Bohr.
How did John Dalton Conrtibute to the Atomic theory?
He did experiments that allowed him to develop, a refine and support hypothesis about matter.
What did John Dalton discover/come up with?
All matter is made up of small particles called atoms
Atoms cannot be created, destroyed, or divided.
All atoms of the same elemt are the identical.
Differnt atoms combine in simple whole-number ratios.
How did JJ Thomspon contribute?
expanded on the ideas of the electron.
How did Ernest Rutherford contribute?
expanded on the nucleas
How did Neils Bohr contribute?
expanded on the ideas of energy levels
What is the smallest particle of an element?
an atom
What is atom made up of?
the nucleas, and electrons
What is the nucleas made from?
protons and neutrons
What is the nucleas?
the center region of an atom.
How many protons does the nucleas of most hydrogen contain?
1
the nucleas of all other atoms cpentain both____
protons and neutrons
What is the atomic mass?
the total number of protons and neutrons
A protons is ________ and a neutron is __________
a proton is positive charged, and a neutrons is negatively charged.
What does the number of protons in a nucleas determine?
the atomic number of the nucleas and the identity of an atom.
How much do electrons account for of the volume in an atom.
99.99%
What is the region that electrons ocuppy called?
energy shells
What do energy shells do?
they surround the nucleas
What is the electron like?
a spread out cloud of high energy that exists in the whole region. (electron cloud)
What is a neutral atom?
a not charged atom
What is the number of protons in a neutral atom is equal to the number ____
electrons ina neutral atom
Who created the first periodic table?
Dmitri Mendeleev
How is the modern periodic table organized?
according to atomic number.
What is the atomic number in a periodic table?
the number of protons in an atom
What does the periodic table acknowledge?
the existence and properties of all elements.
What are elements composed of?
one type of atom
atoms that can exist individually or in compounds (molecules)
cannot be separated or broken down by physical or chemical changes.
because many elements have different names in different languages chemist use_______
chemical symbols for them
All elements are represented by what?
represented by symbols
How many letters do chemical symbols consist of?
one or two letter
What is a period on a periodic table?
the set of all elements in a given row across the table.
What is a family/group in a periodic table?
the set of all elements in a given column going down the table.
periods and groups/families have the
same number of electrons on the outermost shell.
What does having the same amount of electrons not the outer most shell mean for families/groups and periods?
they have similar chemical properties.
Note 
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