AND ANSWERS WITH COMPLETE
SOLUTIONS
The statement "If I add cold milk to hot coffee the temperature will decrease," is a? -
ANSWERSClaim, always include an explanation and reasoning to the claim.
Scientific Model - ANSWERSModels are used to make testable predictions
How much is a picometer? - ANSWERS0.1 x 10^-12 meters
Atomic Force Microscopy/ Scanning Tunneling Microscopy - ANSWERSMicroscopes
that now allows us to view atoms.
Leaves are green in the summer because? - ANSWERSA plant's leaves are green in
the summer because they contain chlorophyll. Chlorophyll is a natural pigment that
absorbs all wavelengths in the visible spectrum except green.
How many naturally occurring elements exist? - ANSWERS91
What was Dalton's Atomic theory? (1808) - ANSWERS- Elements are composed of
small particles called Atoms.
- Atoms of a given element are different from atoms of other elements.
-Chemical reactions happen when atoms are rearranged.
- Compounds contain 2 or more elements.
What was J.J. Thomson's experiment, and what did he discover? - ANSWERSUsing a
Cathode Ray Tube, he noticed that particles emerged to the cathode disk, and moved
to another, the anode. These particles could be deflected by electrical fields that would
indicate that they would be negatively charged. They were also deflected by magnetic
fields, which showed the particles carried the charge as the ray was bent. The most
important observation was that the type of cathode used did not matter, as these
particles were still emitted. Therefore, Thomson deduced that the particles were
universal and were in fact negatively charged components of the atom. (The Electron)
What was Ernest Rutherford's experiment, what did he discover? - ANSWERSErnest
Rutherford fired Alpha particles (Hydrogen atoms) at a thin sheet of gold foil. Had
Thomson's theory been right about the plum pudding model, then the atoms should
have all passed right through the sheet with no exceptions. However, a small ratio of
these particles were deflected. With this information, Rutherford figured there was a
small dense nucleus in the atom and that most of the atom was empty space.