Elite CHEM AP week 1

In most of its compounds, this element exists as a monatomic cation

• F
• S
• N
• Ca

Which of the following groups has the species correctly listed in order of decreasing radius?

• Cu²⁺, Cu⁺, Cu
• V, V²⁺, V³⁺ 
• F^-, Br^-, I^-
• B, Be, Li

Which of the following elements has the lowest electronegativity?

• F
• I
• Ba
• Al

Which of the following represents the correct formula for hexaammine cobalt (III) nitrate

• Co(NH₃)₆(NO₃)₃
• Co(NH₃)₆(NO₂)₃
• Am₆Co(NO₃)₃
• (NH₃)₆CO₃NO₃

The discovery that atoms have small, dense nuclei is credited to which of the following?

• Einstein
• Dalton
• Bohr
• Rutherford

What is the lowest whole number coefficient for water when the following chemical equation is balanced?
Mn(OH)₂+H₃AsO₄→Mn₃(AsO₄)₂+H₂O

• 6
• 2
• 12
• 3

A green precipitate forms, and the concentration of hydroxide ion becomes very small.  Which of the following correctly places the concentrations of the remaining ions in order of decreasing concentration, when 50.0mL of 0.10M Fe(NO₃)₂ and 50.0mL of 0.10M KOH are mixed

• [Fe²⁺]>[NO₃^-]>[K⁺]
• [Fe²⁺]>[K⁺]>[NO₃^-]
• [NO₃^-]>[K⁺]>[Fe²⁺]
• [K⁺]>[Fe²⁺]>[NO₃^-]

Solutions containing this ion give a reddish-brown precipitate upon standing.

• Cu²⁺
• CO₃^2-
• Fe³⁺
• Al³⁺

14H⁺+6Fe²⁺+Cr₂O₇^2-→2Cr³⁺+6Fe²⁺+7H₂O
The above reaction is used in the titration of an iron solution.  What is the concentration of the iron solution if it took 45.20mL of 0.1000M Cr₂O₇^2- solution to titrate 75.00mL if an acidified iron solution? 

• 0.1000M
• 0.4520M
• 0.3616M
• 0.7232M

Manganese, Mn, forms a number of oxides.  A particular oxide is 49.5% by mass Mn.  What is the simplest formula for this oxide?

• MnO
• Mn₂O₃
• Mn₂O₇
• MnO₂