Chapter One Flashcards
Name the Scientist
“The Skeptical Chemist”
Robert Boyle
Name the Scientist
1661-Experiments w/ pressure/volume of air
Robert Boyle
Name the Scientist
Thought substance=element if it can not be broken down into simpler substances
Robert Boyle
Three Important Laws of Chemistry
Law of Conservation of Mass
Law of Definite Proportion
Law of Multiple Proportions
What does the law of conservation of mass say?
Scientist responsible?
Mass can not be created or destroyed
Lavoisier
What does the law of definite proportion say?
Scientist responsible?
A given compound always contains exactly the same proportion of elements by mass.
Proust
What does the law of multiple proportions say?
Scientist responsible?
Different combo of elemtns to form different compounds
Dalton
Dalton’s Atomic Theory
1.
- each element is made up of tiny particles called atoms
Dalton’s Atomic Theory
2.
- The atoms of a given element are identical; the atoms of different elements are different in some fundamental way or ways
Dalton’s Atomic Theory
3.
- Chemical compounds are formed when atoms of different elemtns combined with each other.
Dalton’s Atomic Theory
4.
- Chemical reactions involve reorganization of atoms-change in way bound together.
What parts of Dalton’s atomic theory were wrong?
- Atoms are not the smallest, protons, neutrons, electrons etc.
- atoms of a given element are not identical, isotopes.
Who was the first scientist to consider atomic mass?
Dalton
Who used atomic masses to arrange 1st periodic table?
Dalton
What flaw did Gay-Lussac and Avogadro discover?
Instead of measuring mass, they measured volumes under same temp and pressure.
What did J.J. Thompson do?
(four things)
Discovered electrons
Cathode Ray Experiment
Calculated charge to mass ratio of electron
“plum pudding model”
Who discovered electrons?
J.J. Thompson
What scientist developed the “plum pudding model”?
J.J. Thompson
What scientist had the cathode ray experiment?
J.J. Thompson
What did Robert Milikan do?
(four things)
- Oil Drop Experiment
- Magnitude and charge of electron
- Calculated mass of electron
- Me=9.11*10-31 kg
Who did the Oil Drop Experiment?
Robert Milikan
Who discovered the magnitude and charge of an electron?
Robert Milikan
Who calculated the mass of the electron?
Robert Milikan
What did Ernest Rutherford do?
(four things)
- Tested Thompson’s “plum pudding model”
- Gold Foil Experiment
- Proposed nuclear atom
- Concluded atom has a dense center of a positive charge
Who tested Thompson’s Plum Pudding Model?
Ernest Rutherford
Who did the gold foil experiment?
Ernest Rutherford
Who proposed the nuclear atom?
Ernest Rutherford
Who concluded that an atom has a dense center of a postive charge?
Ernest Rutherford
Who made the periodic table?
Mendeleev
What is the atomic number?
Number of protons
What is the mass number of an element?
protons + neutrons
Isotopes have _____ _______ chemical properties and behavior, chemistry of an atom is due to it’s ________.
almost identical
electrons
Define Energy
Ability to do work or produce heat.
Work =
F*d
(Force * Distance)
Units of a Joule
kgm2/s2
(mass*distance*acceleration)
Define frequency:
number of waves (cycles) per second that pass a given point in space
Unit of frequency
Hertz (1/s)
Speed of Light
2.997*108 m/s
c=
λv
Define wave
a disturbance or oscillation that travels through matter/space, accompanied by a transfer of energy.
Define electromagneticc waves:
periodic oscillations of transverse electrical & magnetic fields
Electromagnetic spectrum from high energy to low energy
Gamma, X-ray Ultraviolet, Visible, Infrared, Microwaves, Radio
Conclusions of Rutherford’s Gold Foil Experiment
(four things)
- Most of the α- particles passed straight through the foil without suffering any deflection. This shows that most of the space inside the atom is empty or hollow.
- Some of the α- particles suffered deflection by 90° or even larger angels. For this to happen α- particles (positively charged) must approach a heavy positively charged core inside the atom (Like charges repel each other). This heavy positively charged ‘core’ inside the atom was named as nucleus.
- Since the number of α- particles which bounced back was very small, hence, the volume occupied by the nucleus is very small as compared to the total volume of the atom.
- The α- particles have appreciable mass. These are deflected by the nucleus. It means that almost the entire mass of the atom lies at its center, i.e., entire mass of an atom is concentrated inside its nucleus.
