Periodic Trends & Average Atomic Mass DOL

24.1% of all the isotopes of a an element have a mass of 75.23 amu, 48.7% have a mass of 74.61 amu, and 27.2% have a mass of 75.20 amu.
What is the average mass of this element?

• 74.92 amu
• 24.97 amu
• 75.01 amu
• 74.51 amu

An element with 4.35% have a mass of 49.9461 amu, 83.79% have amass of 51.9405 amu, 9.50% have a mass of 52.9407 amu, and 2.36% have a mass of 53.9389amu.

• 51.99 amu
• 52.19 amu
• 53.45 amu
• 17.33 amu

The atom with the largest atomic radius in Group 18 is - 

• Ar
• He
• Kr
• Rn

As you move down a group, atomic radius increases because - 

• you add more and more neutrons
• you add more and more protons
• you add more and more shells (energy levels)
• you add more atomic mass

The atom with the largest atomic radius in Period 4 (row 4) is - 

• K
• Kr
• Fe
• Fe

Francium (Fr) has the lowest ionization energy in Group 1 because - 

• it has the smallest number of valence electrons
• it has the greatest atomic mass
• it has the greatest number of protons, so it attracts its electrons the strongest
• its 1 valence electron is very far from the nucleus, so little energy is needed to remove it

The element with the smallest ionization energy in Period 6 is - 

• Rn
• Cs
• Os
• Tm

Of the halogens, which has the smallest radius?

• F

• Br

• He

• At

Which of the following will have a lower ionization energy than Scandium (Sc)?

• Helium (He)

• Titanium (Ti)

• Calcium (Ca)

• Magnesium (Mg)

Which of the following will have a higher electronegativity than arsenic (As)?

• Carbon (C)

• Neon (Ne)

• Antimony (Sb)

• Germanium (Ge)