Question | Answer |
What is the atom? | The smallest particle of an element that retains the properties of that element. |
If you break up an atom into its subatomic particles, what happens? | It is no longer an element, it can't be called an element. |
Who is Democritus? What did he do for science? Was he ideas based on science? | Lived in the 4th century B.C Democritus was a philosopher that came up with the TERM=ATOM. He defined atoms as the fundamental particles that MAKE UP matter and cannot be seen. Since he was a philosopher IT ISN'T BASED ON SCIENCE NO EXPERIMENTS PERFORMED |
Who is Jhon Dalton? What did he do? | Lived in the early 1800's. First experimental definition. He performed a series of experiments and stated his conclusions in the atomic theory. |
What is the first statement of Dalton's theory? | 1.All elements are composed of tiny INDIVISIBLE particles called atoms. |
What is the second statement of Dalton's theory? | Atoms of the Same element are IDENTICAl. Atoms of Different elements are DIFFERENT. |
What is the third statement of Dalton's theory? | Atoms can form mixtures or chemically combine to form compounds. |
What is the fourth statement of Dalton's theory? | Chemical Reactions occur when Atoms SEPARATE, JOIN AND/OR REARRANGE. Atoms of elements never change into atoms of another element during a reaction. |
What discovery was leaded by J-J Thomson? | In 1890's using the Cathode Ray Tube, he DetermineD the MASS OF AN ELECTRON. He concluded the mas of an electron is much-ch smaller than that of an atom. |
What did J-J Thomson disproved? | Since he could measure the mass of an electron, It DISPROVED one of Dalton's Theory--Atoms aren't indivisible, they are DIVISIBLE. |
What did Millikan discover? DO? | Millikan Quantified the Charge of an electron. |
What is an electron? | Electron is a Subatomic Particle of an atom, It is Negatively Charged, and it is found in the Electron Cloud.During chemical reaction electrons are shared/transferred.(e-) |
Explain the CATHODE RAY TUBE | A tube where all the air has been removed. Electricity can then be passed through it. |
What is a Proton? | A proton is Positively Charged, Subatomic Particles, found in the Nucleus. (p+) |
What is a Neutron? | A neutron is the Uncharged, Subatomic Particle, found in the Nucleus. (n0) |
Relative mass of the subatomic particles | (e- :1/1840)--it's 1840 times smaller than a proton. (p+ :1) and (n0 :1) Protons and Neutrons are the same size. |
Rutherford and his Experiment | Rutherford (1911) was a scientist. His experiment was called The Gold Foil Experiment. He expected all the Alfa Particles to pass through the foil. |
What did Rutherford noticed about his experiment? What happened with the result, were the ones he expected? | Result of the Gold Foil Experiment: Many Alfa particles went straight through, Some DEFLECTED back at large angles. |
What was Rutherford's conclusion? | Some particles deflected because they HIT a LARGE MASS. Also he concluded, Most of an atom is made of Empty Space (reason why most of the particles went through) and Most of the mass is found inaCONCENTRATED-POSITIVELY charge AREA(reasonwhy particlesdefl) |
What is the Nucleus? | Nucleus is the Central Core of an atom and it is composed of protons and neutrons. |