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What is 1 + 3?
True or False: More than three-fourths of the elements in the periodic table are nonmetals.
False- most are metals
True or False: Group 1A elements (except for hydrogen) are known as the alkali metals.
True or False: Group 3A elements are the alkaline earth metals
False- group 2A elements are the alkaline earth metals
True or False: Group 7A elements are highly reactive nonmetals known as halogens.
True or False: Group 8A elements are very unreactive elements known as transition metals
False- group 8A elements are the noble gases
True or False: Metalloids have properties of both metals and inner transition metals.
False- have properties of metals and non-metals
The idea of arranging the elements in the periodic table according to their chemical and physical properties is attributed to
Mendeleev left spaces in his periodic table and predicted several elements and their
Mendeleev attempted to organize the chemical elements based on their
Mendeleev noticed that properties of elements usually repeated at regular intervals when the elements were arranged in order of increasing
Mendeleev is credited with developing the first successful
Mendeleev did not always list elements in his periodic table in order of increasing atomic mass because he grouped together elements with similar
In developing his periodic table, Mendeleev listed on cards each element's name, atomic mass, and
Mendeleev predicted that the spaces in his periodic table represented
Mendeleev's table was called periodic because the properties of the elements
The person whose work led to a periodic table based on increasing atomic number was
Moseley's work led to the realization that elements with similar properties occurred at regular intervals when the elements were arranged in order of increasing