Polyatomic Ions and Acids
Which of the following is a polyatomic ion? (a) Na+ (b) NH4+ (c) Cl- (d) K+
NH4+ (Ammonium)
What type of bond involves electron transfer between a metal and a nonmetal?
Ionic bond
What is the formula for calculating formal charge?
Valence electrons−Nonbonding electrons−Bonding electrons/2
What does it mean if a molecule is paramagnetic?
It has unpaired electrons.
Explain why some elements make diatomic molecules using MO theory
They have a positive bonding order while others don't Ill probably accept whatever here.
Name the polyatomic ion with the formula NO3−NO_3^-NO3−
Nitrate
What type of bond occurs when electrons are shared equally?
Nonpolar covalent bond
What is the formal charge on oxygen in NO3−?
0 for two oxygens, −1 for one oxygen (total charge = -1).
Which molecular orbital is formed from the head-on overlap of two atomic orbitals?
Sigma (σ\sigma bond
Explain why CCl₄ is nonpolar while CHCl₃ is polar.
CCl4 has symmetrical tetrahedral geometry, making the dipoles cancel out, while CHCl3 is asymmetrical, so dipoles do not cancel.
What type of bond forms when electrons are shared unequally between two atoms?
Polar covalent bond
Explain Type 2 naming conventions and when to use it
Between a metal with variable charge and a non metal. The charge of the metal should be in parentheses and the nonmetal will come second ending in ide.
Which molecule has resonance: CO2CO_2CO2, O3O_3O3, H2OH_2OH2O, or CH4CH_4CH4?
O3
How do you determine bond order from an MO diagram?
(bonding electrons−antibonding electrons)/2
What is the coefficient for Al in the balanced reaction:
Al+O2→Al2O3?
4Al+3O2→2Al2O3
CO₂ and H₂O both have polar bonds. Why is CO₂ nonpolar while H₂O is polar?
CO₂ is linear (180°), so dipoles cancel; H₂O is bent (104.5°), so dipoles do not cancel, making it polar.
Which elements can form expanded octets, and why?
Elements in period 3 or higher (e.g., P, S, Cl) due to access to d orbitals.
How many total resonance structures exist for carbonate ion (CO3^2-)?
3
According to MO theory, is CO diamagnetic or paramagnetic?
Diamagnetic
Why is XeF₄ square planar while SF₄ is seesaw-shaped?
XeF₄ has two lone pairs, symmetrically placed, making the shape square planar, while SF₄ has one lone pair, leading to an asymmetrical seesaw shape.
What is the correct name for H2PO4−H_2PO_4^-H2PO4−, and what type of acid is it derived from?
Dihydrogen phosphate, derived from phosphoric acid.
What is the bond order of the cyanide ion (CN−CN^-CN−) according to molecular orbital theory?
Bond order = 3
Why is the most stable resonance structure the one where formal charges are minimized?
Structures with the least separation of charge and formal charges closest to zero are most stable, as they better reflect electron distribution.
Give me Bond angles for Tetrahedral and Triagonal Bipyrimidal
97.5 and 120 and 90
Why do lone pairs in a trigonal bipyramidal molecule always occupy equatorial positions first?
Lone pairs experience less repulsion in equatorial positions because they are 120° apart, whereas in axial positions, they would be 90° from three bonded atoms, causing greater repulsion.