Atoms
This particle has a positive charge. What is it?
A proton
Which classification contains elements that are good conductors of electricity?
Metals
What do we call the vertical columns of the periodic table?
Groups
What particle changes when isotopes of an element are compared?
Neutrons
What is radioactive decay?
The breakdown of an unstable atom into a more stable atom.
This particle has almost no mass and a negative charge. What is it?
an electron
Oxygen belongs to which classification?
Non-metal
What do we call the horizontal rows of the periodic table?
Periods
Carbon-12 and Carbon-14 have the same number of what particle?
Protons
Which type of radiation can be stopped by paper?
Alpha
The mass number of an atom is found by adding these two particles together. What are the two particles?
Protons and neutrons
Why is silicon classified as a metalloid?
It has properties of both metals and non-metals.
An element is in Period 3. How many occupied electron shells does it have?
3
Carbon-14 has 6 protons and 8 neutrons. What is its mass number?
14
Which type of radiation is actually an electron?
Beta
A neutral atom has 12 protons. How many electrons does it have?
12
At room temperature, many non-metals exist in what state?
Gas
An element is in Group 7. How many valence electrons does it have?
7
Why is carbon's relative atomic mass 12.01 instead of exactly 12?
Different isotopes exist in different abundances.
A sample starts with 80 atoms. One half-life passes. How many atoms remain?
40
Scientists discovered atoms are mostly empty space after this famous experiment. What was the experiment called?
Rutherford's Gold Foil Experiment
A new element is found to conduct electricity better than sulfur but worse than copper. Which classification is it most likely in?
Metalloid
Why do elements in the same group react in similar ways?
They have the same number of valence electrons.
Which isotope of carbon is used in carbon dating?
Carbon-14
A fossil contains 25% of its original carbon-14. How many half-lives have passed?
2