Practice MDCAT 2026 questions with answers and explanations.
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Each carbon has three sigma-bonding regions.
The remaining p orbitals form the pi bond.
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Deposition is the reverse of sublimation.
Frost formation is a familiar example.
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Each carbon has two electron domains.
Sp hybridization gives linear geometry and leaves two p orbitals for pi bonds.
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At equilibrium, evaporation and condensation rates are equal.
Vapor pressure increases with temperature.
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Helicase breaks hydrogen bonds between base pairs.
It opens the replication fork.
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Three electron groups arrange about 120 degrees apart.
They lie in one plane.
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Four electron groups point toward tetrahedral corners.
The ideal bond angle is about 109.5 degrees.
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Carbon in methane has four bonding pairs and no lone pairs.
The molecular geometry is tetrahedral.
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Nitrogen has three bonds and one lone pair.
The lone pair changes the molecular shape from tetrahedral electron geometry.
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Oxygen has two bonding pairs and two lone pairs.
Lone-pair repulsion produces a bent molecule.
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Carbon has two electron domains from the two double bonds.
They arrange 180 degrees apart.
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Boron has three bonding regions and no lone pairs.
The molecule is planar with approximately 120-degree angles.
