Metal, nonmetal or metalloid?
Potassium (K)
alkali metal
Ca and K have the same number of _______
electron shells
Group 16, period 2
Oxygen (O)
Horizontally OR left to right OR across
Is 14C an ion or an isotope?
Isotope
Arsenic (As)
metalloid
O and S have the same number of _____ ______
valence electrons
Fifth period, same group as Fluorine
Iodine (I)
Groups move _____ the periodic table
Down OR top to bottom OR vertically
Is Mg 2+ an example of an ion or an isotope?
Ion
Beryllium (Be)
alkaline metal
Cl- and Ar have the same number of _____
electrons
Period 4, group 17
Bromine (Br)
The modern periodic table is ordered on the basis of ____ which is equal to the number of _____ in the atom.
atomic number, protons
How many electrons are there in Mg2+?
10 electrons
12 (atomic #) - 2 (charge) = 10 electrons
Selenium (Se)
nonmetal
H+ and He have a difference of __ electrons
2
Period 4, Group 4
Tin (Ti)
All members of Group 1 on the periodic table have similar reactivity because...
They have similar outer-shell electron configurations
Isotopes have the same number of ______, but a different number of _____ in their nuclei.
protons, neutrons
Iridium (Ir)
transition metal
Na+ and O2- have _____ number of electrons (the same or different?)
the same
O2- (10 electrons)
Na+ (10 electrons)
Alkaline earth metal in the same period as Krypton
Calcium (Ca)
The number under the element name is the ____
atomic mass
What is the charge of an element with 40 neutrons, 35 protons, and 34 electrons? What is the atomic mass?
Charge: +1
Mass: 75