Question

periodic table basics practice
choose all that apply to iridium
☐ transition metal
☐ group 9
☐ 6 electron energy level
☐ period 4
☐ 77 protons
☐ same period as europium
☐ same group as cobalt
☐ same period as rubidium
☐ forms anions when reacting
possible points 1.67

Explanation:

• Iridium (Ir) is a transition metal (d - block element).
• It is in Group 9 (along with Co, Rh).
• Its atomic number is 77, so 77 protons.
• It is in Period 6 (energy level \(n = 6\)), rubidium (Rb) is in Period 5, europium (Eu) is in Period 6, cobalt (Co) is in Group 9. Metals like Ir form cations, not anions. Period 4 is incorrect.

Answer:

• Transition Metal
• Group 9
• 6 electron energy level
• 77 protons
• Same period as europium
• Same group as cobalt
• Same period as rubidium (Note: Rubidium is in Period 5, Iridium is in Period 6 - this is an error in the original problem's option or a mis - recall. Correctly, Iridium is in Period 6, Rubidium in Period 5. But based on the given options and standard knowledge of Iridium: The correct ones are Transition Metal, Group 9, 6 electron energy level, 77 protons, Same period as europium, Same group as cobalt. The "Same period as rubidium" is incorrect. If we follow the problem's options and standard Iridium properties:

Final correct options (after correcting the rubidium error):

• Transition Metal
• Group 9
• 6 electron energy level
• 77 protons
• Same period as europium
• Same group as cobalt