Facebook
Google
GitHub
LinkedinBasic Electricity
Atomic Structure
11 questions By Tony R. Kuphaldt
-
Question 7 of 11
Some of the particles comprising atoms react to each other in a way that scientists categorize as electric charge. There are two fundamental types of electric charge: positive and negative. Identify the respective charges of the following particles:
- • Electrons
- • Protons
- • Neutrons
What would happen if you placed two electrons near each other in free space? Would they repel each other or attract each other? How about two protons? How about an electron and a proton? How about a neutron and a proton?
Reveal answerI’ll let you research which charge type (positive or negative) is characteristic of electrons, protons, and neutrons!
As for their respective physical reactions, particles of differing charge are physically attracted to each other while particles of identical charge repel each other.
Notes:Many students will want to know “why?” in response to electrical charges. The technical answer has to do with electric fields extending through space, but this may be a philosophically impossible question to answer. The concept of charge was invented to explain the physical behavior of electrical attraction and repulsion, but coining a term to explain a phenomenon does nothing to explain why that phenomenon occurs.
Still, this is a worthwhile subject for discussion, especially if students have done their research well and know something about the history of electricity.
-
Question 8 of 11
Atoms are very, very small pieces of matter. This fact should go without saying, but it behooves us to be reminded of just how small atoms are. Chemists and physicists use a unit of measurement to represent quantities of different materials based on how many atoms (or molecules) there are in a particular sample. This unit of measurement is called the mole.
1 mole of pure iron metal weighs about 56 grams. Based on the definition of a mole, how many atoms of iron are in this 56 gram sample?
Reveal answerThere are approximately 6.022 ×1023 atoms in this 56 gram sample of iron. What does this quantity look like when written in non-scientific notation?
Notes:The purpose of this question is twofold: to reinforce the fact that atoms are really, really tiny, and to introduce students to the use of scientific notation.
-
Question 9 of 11
How many atoms of iron are there in a sample measuring 2 ×103 moles? Determine the answer without using a calculator!
Reveal answerThere are 1.2044 ×1027 atoms of iron in this sample.
Notes:One of the benefits of using scientific notation is that it allows us to easily perform multiplication and division using very large and very small numbers.
Question 11 answer appears to be typed incorrectly. It should be the following: A = P + N.