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1
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Elements in group 2 are all called alkaline earth metals. What is most similar about the alkaline earth metals?

A
how many total electrons they have
B
which chemical properties they have
C
which period they are most often found in
D
how many protons and neutrons they have
2
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Based on the information in the table, which elements are most likely in the same periods of the periodic table? Facts about Five Elements Element Atomic mass amu Total electrons Valence electrons Year isolated Aluminum Al 27 13 3 1825 Boron cap b 11 5 3 1808 Carbon cap c 12 6 4 1803 Gallium Ga 70 31 3 1875 Germanium Ge 73 32 4 1886

A
Boron and carbon are likely together in one period because they have very close atomic masses, while gallium and germanium are likely together in another period because they have very close atomic masses.
B
Aluminum, boron, and carbon are likely together in one period because they were first isolated in the first half of the 1800s, while gallium and germanium are likely together in another period because they were first isolated in the second half.
C
Boron and carbon are likely together in one period because they each end in “-on,” while aluminum, gallium, and germanium are likely together in another period because they each end in “-ium.”
D
Aluminum, boron, and gallium are likely together in one group because they have the same number of valence electrons, and carbon and germanium are likely together in another group because they have the same number of valence electrons.
4

The element phosphorus is located to the right of the element magnesium along the same period in the periodic table. Which best describes the relationship of the elements?

A
Magnesium is in the same category as phosphorus.
B
Phosphorus has similar chemical properties as magnesium.
C
Magnesium has a larger atomic number.
D
Phosphorus has a larger atomic mass.
5

Based on the information in the table, which two elements are most likely in the same group, and why? Facts about Four Elements Element Atomic mass amu Total electrons Valence electrons Year isolated Bismuth Bi 209 83 5 1753 Nitrogen cap n 14 7 5 1772 Oxygen cap o 16 8 6 1772 Sodium Na 23 11 1 1807 Thallium Tl 204 81 3 1861

A
bismuth and thallium, because their atomic masses are very similar
B
bismuth and nitrogen, because they have the same number of valence electrons
C
sodium and thallium, because their names both end in the same suffix: -ium
D
nitrogen and oxygen, because they were both first isolated in the same year
6

Which two chemists organized elements based on properties such as how the elements react or whether they are solid or liquid?

A
Lavoisier and Mendeleev
B
Newlands and Mendeleev
C
Döbereiner and Newlands
D
Lavoisier and Döbereiner
7

Dmitri Mendeleev and Henry Moseley developed their periodic tables about forty years apart. During that time, many discoveries in chemistry were made. Which fact was most likely discovered between the time of Mendeleev’s table and the time of Moseley’s table that helped Moseley develop his version?

A
The number of protons in an atom is different than the atom’s total mass.
B
Different elements can have similar chemical properties even if their atomic masses are different.
C
Atomic mass is the average mass of different samples of the same element.
D
Protons strongly affect an element’s atomic mass, while the electrons in atoms do not.

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