Scientists Timeline

Question 1

measures the earth’s circumference

Answer 1

Eratostenes 240 BC

Question 2

used a telescope to observe that the moons of Jupiter appear to circle Jupiter. This evidence supports the heliocentric model and weakens the geocentric model of cosmos

Answer 2

Galileo Galilei 1609

Question 3

author of the Skeptical Chemist, used an air pump to determine the inverse relationship between pressure and the volume of a gas. this relationship came to be known as name’s law

Answer 3

Robert Boyle 1660-1662

Question 4

used a microscope to observe cells which he describes in his book Micrographia

Answer 4

Robert Hooke 1665

Question 5

the “father of microbiology” discovers microorganisms which he originally named “animalcules”

Answer 5

Anton van Leeuwenhoek 1674-1676

Question 6

made the first quantitative estimate of the speed of light by timing motions of Jupiter’s satellite Io with a telescope

Answer 6

Ole Romer 1676

Question 7

suspends a bowl of water above a beer vat at a brewery and synthesizes carbonated water. he is better known for discovering dephlogisticated air (oxygen)

Answer 7

Joseph Priestly 1767

Question 8

determines that oxygen combines with materials upon combustion thus disproving phlogiston theory

Answer 8

Antoine Lavoisier 1783

Question 9

determines that chemical reactions in a closed container do not alter total mass. from these observations he established the law of conservation of mass

Answer 9

Antoine Lavoisier 1789

Question 10

tests his hypothesis for the protective action of mild cowpox infection for smallpox, the first vaccine

Answer 10

Edward Jenner 1796

Question 11

used a torsion bar experiment to measure the density of the earth. he is also known as the discoverer of hydrogen

Answer 11

Henry Cavendish 1798

Question 12

used the double-slit experiment to demonstrate the wave particle duality of light

Answer 12

Thomas Young 1801

Question 13

used electrolysis to isolate elements potassium, sodium, calcium, strontium, barium, magnesium, and chlorine

Answer 13

Humphry Davy (187-1810)

Question 14

studied reactions among gases and determined that their volumes combine chemically in simple integer ratios

Answer 14

Joseph Louis Gay-Lussac (1809)

Question 15

discovers the connection of electricity and magnetism by experiments involving a compass and electric circuits. this is later termed electromagnetism

Answer 15

Hans Christian Orsted 1820

Question 16

studied very small pollen particles in water under the microscope and observes Brownian motion which was later named in his honor

Answer 16

Robert Brown 1827

Question 17

synthesizes the organic compound urea using inorganic reactants disproving the application of vitalism to chemical processes

Answer 17

Fredric Wohler 1828

Question 18

measured the rates of effusion for different gases and establishes Graham’s law of effusion and diffusion

Answer 18

Thomas Graham 1833

Question 19

arranged to have trumpets play from a passing train. the ground observed pitch was higher than that played when the train was approaching then lower that as the train passed and moved away demonstrating the name Effect

Answer 19

Christian Doppler 1845

Question 20

name pendulum is first exhibited. it demonstrates the Coriolis effect and the rotation of the Earth 1851

Answer 20

Leon Foucault 1851

Question 21

his experiments with the garden pea led him to surmise many of the fundamental laws of genetics (dominant vs recessive genes, the 1-2-1 ratio, etc). his work is best summarized with the Law of Segregation and the Law of Independent Assortment

Answer 21

Gregor Mendel 1856-1863

Question 22

used S-shaped flasks to prevent spores from contaminating broth, disproving the theory of Spontaneous Generation (also known as abiogenesis). This experiment was an extension of the rancid meat experiement of Frencesco Redi

Answer 22

Louis Pasteur 1861

Question 23

discovered a voltage across a conductor with a transverse applied magnetic field, the name Effect

Answer 23

Edwin Hall 1879

Question 24

saved Joseph Meister after the 9 year old was bitten by a rabid dog. this was the first successful vaccine against rabies

Answer 24

Louis Pasteur 1885