neutrons
Mendeleev created the first periodic table by arranging elements in order of ____.
a.decreasing atomic mass
b.increasing atomic mass
c.increasing atomic number
d.increasing melting points and densities
b.increasing atomic mass
Nonmetals are ____________________ conductors of heat and electricity.
poor
A material is said to be ductile if it ____.
a.can be pulled out, or drawn, into a long wire
b.can be hammered or rolled into flat sheets and other shapes
c.can transfer heat or electricity to another material
d.is a mixture of a metal with at least one other element
a.can be pulled out, or drawn, into a long wire
Which of the following statements about transition metals is true?
a.They are never found uncombined in nature.
b.They include familiar metals such as gold, silver, copper, and nickel.
c.They are so soft that they can be cut with an ordinary knife.
d.They are the most reactive of all the types of metals.
b.They include familiar metals such as gold, silver, copper, and nickel.
The maximum number of electrons the third level of an atom can hold is ____
a.2
b.8
c. 18
d. 32
c. 18
How did chemists change Mendeleev’s periodic table in the early 1900s?
a.They included chemical properties such as bonding power.
b.They included physical properties such as melting point and density.
c.They used atomic mass instead of atomic number to organize the elements.
d.They used atomic number instead of atomic mass to organize the elements.
d.They used atomic number instead of atomic mass to organize the elements.
____________________ have no charge; they are neutral.
Neutrons
In an atom, the number of protons equals the number of ____.
a.nuclei
b.electrons
c.neutrons
d.isotopes
b.electrons
Which group of elements shares characteristics with both metals and nonmetals?
a.salts
b.metalloids
c.halogens
d.lanthanides
b.metalloids
The 2nd energy level of an atom can hold a maximum of ____ electrons with the exception of hydrogen and helium.
a.2
b.8
c. 18
d. 32
b. 8
Most metals are NOT ____.
a.ductile
b.good conductors of heat and electricity
c.liquid at room temperature
d.malleable
c.liquid at room temperature
Each element is given a specific ____________________ that usually consists of one or two letters.
chemical symbol
The elements in a column of the periodic table ____.
a.have similar properties
b.are in the same period
c.have the same atomic mass
d.have very similar chemical symbols
a.have similar properties
The elements that do not ordinarily form compounds are ____.
a.elements in the carbon family
b.metals
c.halogens
d.noble gases
d.noble gases
The modern periodic table is organized according to ____________________.
atomic number
The ____________________ is the very small center core of an atom.
nucleus
What information in the periodic table indicates the number of protons in an atom?
a.the position of the element in its column
b.the element’s chemical symbol
c.the element’s atomic number
d.the element’s atomic mass
c.the element’s atomic number
Which particles in atoms have a negative electric charge?
a.electrons
b.protons
c.neutrons
d.nuclei
a.electrons
The horizontal rows in the periodic table are known as ____________________.
periods
Which group contains the most elements?
a.metalloids
b.nonmetals
c.metals
d.transition elements
c.metals
Part of ____________________ atomic theory was atoms cannot be created or destroyed in any chemical change, only rearranged.
Daltons
The two most common alkaline earth metals are ____.
a.copper and zinc
b.iron and silver
c.sodium and potassium
d.calcium and magnesium
d.calcium and magnesium
Fluorine, chlorine, bromine, and iodine are part of a family called ____.
a.noble gases
b.metalloids
c.halogens
d.alkali metals
c.halogens
The elements in a group of the periodic table have ____________________ characteristics