Atoms Assessment
How many electrons does an element need in its outermost shell to be stable? How are H and He an exception to this rule?
An element needs 8 valence electrons in its outermost shell to be stable. H and He only need 2 in their outermost shell to be stable because they only have enough electrons to fill one shell.
What is an isotope and how does it affect a particular atom's mass?
An isotope is a variance in the number of neutrons in an atom, increasing or decreasing the mass (number).
How much smaller on average are the electrons, compared to the protons and neutrons?
An proton/neutron is 1836 times bigger than an electron.
In a life sized model, how far away would the electrons be from the central nucleus?
The closest electron would be about 6 soccer/football fields away.
What are the electrons in the outermost shell called?
The electrons in the outermost shell are called valence electrons.
How does an atom act like a solid, despite being mostly empty space between the nucleus and the electrons?
The electrons move so rapidly it seems to create a wall or solid like fan blades, when they are still, you can easily put your hand through, but when they are in motion, your hand bounces back.
How many electrons does the fifth energy level/shell hold?
The fifth energy level holds 50 electrons.
How many electrons does the first energy level/shell hold?
The first energy level holds 2 electrons.
What is special about the way you write an atoms' chemical symbol if it is more than one letter?
The first letter would be uppercase, the remaining letters, lowercase.
How many electrons does the fourth energy level/shell hold?
The fourth energy level holds 32 electrons.
What can you identify about an element's atomic structure based on its group on the periodic table? Give 3 examples.
The group number gives you the number of valence electrons an element will have and its reactivity level. Ex. Francium is in group 1, and is very reactive due to the fact it has 1 valence electron. Ex. Calcium is in group 2, and is less reactive than elements in group 1, but is still quite reactive due to the fact it has 2 valence electrons. Ex. Boron is in group 13, and is less reactive than elements in group 2, but is still very reactive due to the fact it has 3 valence electrons.
What can you identify about an element's atomic structure based on its period on the periodic table? Give 3 examples.
The period number gives you the number of energy levels/shells an element has. Ex. Francium is in period 7 and has 7 shells. Ex. Calcium is in period 3 and has 3 shells. Ex. Boron is in period 2 and has 2 shells.
How many electrons does the second energy level/shell hold?
The second energy level holds 8 electrons.
How many electrons does the sixth energy level/shell hold?
The sixth energy level holds 72 electrons.
How many electrons does the third energy level/shell hold?
The third energy level holds 18 electrons.
What are the three subatomic particles that currently make up an atom and what is the corresponding charge for each?
The three are: Protons + Electrons - Neutral
What are the two subatomic particles that make up most of the atoms mass?
The two subatomic particles that make up most of the atoms mass are protons and neutrons.
The word atom comes from the Greek origin _____ meaning _____.
The word atom comes from the Greek origin atomos meaning indivisible.
How many atoms on the periodic table are naturally occurring and where did the others originate?
There are 92 naturally occurring atoms on the periodic table, the rest are man-made.
What is the subatomic particle that makes up most of an atom's volume?
Electrons make up most of an atom's volume.
What information about a particular atom can be found just by looking at its box on the periodic table?
Looking at an atom's box on the periodic table, you can find its mass number, giving you its protons and electrons, its atomic mass, giving you its number of neutrons, and its chemical/atomic symbol.
How many atoms can fit on the tip of a pin?
One million atoms can fit on the tip of a pin.
Why don't all atoms' chemical symbols start with the same letter as their elemental names?
Some atoms' chemical symbols are based off of their Latin or Greek names.
