CEM 141 MSU Exam 1 Questions and Answers(A+ Solution guide)
9 views 0 purchase
Course
CEM 141 MSU
Institution
CEM 141 MSU
The statement "If I add cold milk to hot coffee the temperature will decrease," is a? - Claim,
always include an explanation and reasoning to the claim.
Scientific Model - Models are used to make testable predictions
How much is a picometer? - 0.1 x 10^-12 meters
Atomic Force Microscopy/ Scanni...
CEM 141 MSU Exam 1 The statement "If I add cold milk to hot cof fee the temperature will decrease," is a? - ✔✔ Claim, always include an explanation and reasoning to the claim. Scientific Model - ✔✔ Models are used to make testable predictions How much is a picometer? - ✔✔ 0.1 x 10^ -12 meters Atomic Force Microscopy/ Sc anning Tunneling Microscopy - ✔✔ Microscopes that now allows us to view atoms. Leaves are green in the summer because? - ✔✔ A plant's leaves are green in the summer because they contain chlorophyll. Chlorophyll is a natural pigment that absorbs all waveleng ths in the visible spectrum except green. How many naturally occurring elements exist? - ✔✔ 91 What was Dalton's Atomic theory? (1808) - ✔✔ - Elements are composed of small particles called Atoms. - Atoms of a given element are different from atoms of oth er 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? - ✔✔ Using 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 Electr on) - ✔✔ What was Ernest Rutherford's experiment, what did he discover? - ✔✔ Ernest 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 a ll 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. What is the di fference between Law and Theory? - ✔✔ A law describes - tells you what happens A theory explains - tells you why it happens How big is an atom (H)? - ✔✔ About 0.1 nanometer (0.1 x 10 -9m) Which is biggest? Atom, Molecule, Cell, or it depends? - ✔✔ Where did the idea of atoms come from? - ✔✔ The Greeks Atoms - ✔✔ The smallest unit of an element What is the evidence from Thomson's experiment that all atoms contain electrons? - ✔✔ The particles are identical regardless of the identity of the cathode(whe re they were emitted from). What is an alpha particle? - ✔✔ Has 2 protons and 2 neutrons. It is the nucleus of a Helium atom. Coulomb's Law - ✔✔ Negative and positive charges attract and like charges repel. 4 Types of Forces - ✔✔ Gravitational, Electromagn etic, Strong Nuclear, Weak Nuclear Gravitational Force - ✔✔ Responsible for attraction between objects that have mass.
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller PatrickKaylian. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $7.99. You're not tied to anything after your purchase.
