Atomic structure
What are the three main subatomic particles?
3 main parts of an atom?
Protons, neutrons and electrons
What is the symbol for Gold?
Au
Elements in the same vertical column belong to the same what?
Group
Who is most commonly attributed for creating an early periodic table and left gaps for undiscovered elements?
Dmitri Mendeleev
What is the name of the element's whose symbol is W?
Tungsten
An atom has 12 protons and 12 neutrons. What is its mass number?
24
What is the difference between a group and a period?
A group is a vertical column; a period is a horizontal row
What properties do Group 8 have in common?
Gas and are not as reactive.
Mendeleev left Group 3, Period 5 empty when he first drafted the periodic table.
What is now in Group 3, Period 4?
Gallium (Ga)
Which element has the atomic number of 21?
Scandium
An atom has 9 protons, 10 neutrons and 9 electrons. What is its atomic number and overall charge?
Atomic number = 9; overall charge = 0 (neutral)
Why is the modern periodic table arranged by atomic number rather than atomic mass?
Does atomic number identify the element?
Atomic number gives the number of protons and correctly identifies each element.
Three elements in the same group have similar chemical properties. What pattern does this suggest?
Elements in the same group often have similar properties.
Why did Mendeleev leave gaps in his periodic table?
He predicted that undiscovered elements existed and wanted to preserve the patterns in his table
Element A conducts electricity and is shiny. Element B does not conduct electricity and is brittle. Which evidence suggests A is a metal?
Conductive and shiny appearance.