Review Over Periodic Table, Periodic Trends, Atomic Theory, Chemical Formulas, and the Mole

Chlorine, bromine, and iodine were grouped together in the earliest forms of the periodic table, including the table developed by Mendeleev. What was an organizing principle in this grouping at that time?

• Atoms of the three elements had approximately the same mass.

• The three elements react the same way with other elements.

• The elements have the same number of valence electrons.

• These three elements are all gases at room temperature

Tags

NGSS.HS-PS1-1

The early periodic table organized the elements in periods of increasing atomic mass. What information is currently used to organize the elements on the periodic table?

• number of valence electrons 
• number of energy levels 
• atomic number 
• ionic radius 

Tags

NGSS.HS-PS1-2

All elements found on the left side of the Periodic Table of the Elements have what properties in common?

• They conduct heat and electricity 
• They are all gases 
• They are brittle and dull
• They are radioactive

Which of these elements has an electron structure most similar to that of element X?

• 1

• 2

• 3

• 4

Tags

NGSS.HS-PS1-1

Based on their locations in the periodic table, which element has chemical properties most similar to those of calcium, Ca?

• beryllium, Be
• potassium, K
• titanium, Ti
• yttrium, Y

Tags

NGSS.HS-PS1-1

The number of valence electrons in an element affects the reactivity of that element. Which element listed has the fewest valence electrons?

• beryllium (Be)
• sodium (Na) 
• oxygen (O) 
• neon (Ne)

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

According to the Periodic Table of the Elements, which set of elements has similar properties?

• H, C, I
• He, H, Al
• He, Ne, Ar
• Na, Ca, Al

Tags

NGSS.HS-PS1-1

Hydrogen is a gas at a room temperature, but it is found with the alkali metals in group 1 on the periodic table. Which is the most likely reason hydrogen is grouped with alkali metals?

• All group 1 elements have the same number of protons.

• Alkali metals are gases at room temperature.

• Hydrogen is a metal.

• All group 1 elements have one valence electron.

Tags

NGSS.HS-PS1-1

What is the family name of this group of elements? 

• Alkali metals 
• Halogens 
• Noble Gases 
• Alkali Earth Metals 

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

Which element has 2 valence electrons? 

• cesium (Cs) 
• magnesium (Mg)
• boron (B)
• argon (Ar) 

Tags

NGSS.HS-PS1-1