Final history Flashcards
What is the first component to daltons atomic theory
All matter is made of atoms. Atoms are indivisible and indestructible
What is the second component to daltons atomic theory
All atoms of a given element are identical in mass and properties
What is the third component to daltons atomic theory
Compounds are formed by a combination of two or more different kinds of atoms
What is the fourth component to daltons atomic theory
A chemical reaction is a rearrangement of atoms
Dalton experimented where
England during the 1800s
Dalton thought each element had a unique
Mass
Daltona atom did not describe any
Subatomic particles
Where were Thomson and Millikan educated
Oberlin college Ohio
Millikans oil drop experiment determined
The mass to charge ratio of the electron by suspending an oil drop of known mass using a magnetic field
What experiment takes Thomson to his plum pudding model
Cathode ray tube
What about thomsons plum pudding model that is different from previous models
Showed that most of the atom was positively charged
What did James Chadwick discover
Neutrons in the nucleus
What observation led Chadwick to conclude there must be something besides just the proton in the nucleus of atoms
By hitting the beryllium plate, he discovered some particles were neutral and called them neutrons
The discovery of the neutron led to the discovery and explanation of
How the nucleus is held together known as the Nuclear Strong Force
James Chadwick won the Nobel prize in
Physics in the year 1935
Rutherfords contribution to the atomic theory is most famously recognized by
His gold foil experiment
Rutherfords experimentation led to the discovery and acceptance of
The nucleus
Before rutherfords experimentation, the atom was thought to be ——
However after his research it was accepted that an atom is ——
A solid particle
Mostly empty space
Where did Bohr work
Copenhagen Denmark
In us on manhatten project
Bohr proposed
That electrons occupy energy levels thus preventing them from moving into the nucleus
Bohr discovered that electrons absorb only specific amounts of —-. They Lose it in the form of —- that we see as —-
Energy
Radiation
Colored light
Bohrs model only worked for
Elements with only one electron
What was heisenberga first name
Werner
Heisenberg was rewarded the novel peace price in physics in 1932 for the creation of
Quantum mechanics
Before de broglie it was thought that electrons moved in orbits around the nucleus, what did his findings change this understanding to be
Wave like properties, moving in waves instead of circular orbits around nucleus
De broglies findings explained
Why there were restrictions on the locations of electrons
Schrödinger was born on
August 12th, 1887
Schrödinger and who had very similar approaches to the description of electron movement
Neil’s Bohr
Why isn’t schrödingers model easily represented in a picture
Predicts the odds of an electrons location and does not give its specific path, so can’t draw it
When does heat increase but temp doesn’t on a heating curve
When it’s goings through a phase change
Why does it take more heat to boil water than to melt water
The attraction is stronger between a solid and liquid, distance smaller
Takes more energy because molecules are more spread out in boiling a liquid
Formula for determining energy at a phase (solid, liquid, gas) on heating curve
Q=mc/\T
Formula for determining energy at a phase change (vaporization, melting) on a heat curve
Q=moles of sub X /\H of phase change
Q=mol*/\H
Specific heat of water
4.18j/g•c
How do hot and cold packs work
Hot packs- chemical reaction release energy (exo)
Cold packs- chemical reaction take in energy (endo)
Thermochemistry
The study of energy changes associated with chemical reactions
Heat
The transfer of thermal energy between two bodies at different temps
Thermal energy
Energy associated with random movement of atoms or molecules
System
The specific part of the universe that one is studying
Surroundings
The rest of the universe, everything but the system
Universe
The combination of the item under investigation and the immediate factors that can influence it
Types of systems
Open, closed, isolated
Open system
Allows transfer of both h energy and mass (coffee cup)
Closed system
Energy can leave but mass can not, soda can
Isolated system
Mass not energy transfer can happen (doesn’t exist)
Enthalpy (h)
The total energy of a system; some of which is stored as chemical energy in the chemical bonds
In chemical reactions where does energy come from
Bonds broken or made
Energy absorbed from break bonds never equal that released in making new bonds
Triangle H means
Change in enthalpy, heat given off or absorbed during reaction
Triangle H formula equals
H products minus H reactants
Standard enthalpy of reaction is
Triangle H ø
Standard conditions
Exothermic reaction,
Heat released, negative
Calorimetry
The temp of a liquid inside a well insulated container (calorimetry) is measured before and after a reaction
Specific heat capacity
The amount of energy required to raise the temp of one gram of a substance by one degree
