Elements that have properties of both metals and nonmetals are
What is semiconductors
100
Mendeleev left gaps in his periodic table because ____________
What is no elements fit
100
Most elements are of which category
What is metals
100
AS you move left to right across the periodic table, elements become
What is less metallic
200
Mendeleev arranged the known chemical elements in a table according to increasing
What is atomic mass
200
Reactive elements of Group 17 that are poor conductors
What is Halogens
200
Elements that belong to group 3-12
What is transition metals
200
Highly reactive elements that belong to Group 1
What is Alkali Metals
200
Which of the following is a noble gas?
A. Helium
B. Boron
C. Hydrogen
D. Americum
What is A. Hydrogen
300
In a periodic table, a set of properties repeats from ____ to _____
What is row; row
300
Which is NOT true of elements of the same group?
A. same # of valence electrons
B. share atomic mass #
C. share chemical properties
D. share physical properties
What is B. share atomic mass #
300
Which group exists as a single atom, belongs to group 18, and is a nonmetal?
What is Halogens
300
Loses or gains electrons is called an
What is ion
300
Which of the following is a metal?
A. Tin
B. Copper
C. Cesium
D. All of the above
What is D
400
1/12 the mass of a Carbon-12 unit is called
What is atomic mass unit
400
When Mendeleev organized the elements by atomic mass he found out that certain ______ appear at ______ intervals.
What is properties; certain
400
Oxygen falls under what category of the periodic table?
What is nonmetal
400
True/ False
Most nonmetal are brittle
What is true
400
What is the chemical name for Co
What is Cobalt
500
What group and period is the element Boron in?
What is Period 2; Group 13
500
When can semiconductors conduct heat and electricity?
What is under some conditions.
500
List the 3 main groups of elements
What is metals, nonmetals, semiconductors
500
List 3 properties of metals
What is malleable, ductile, good conductors of electricity.
500
none of the metals are _________ at room temperature