Advanced Atomic Concepts
Elements & Their Properties
Bonding & Lewis Structures
Reaction Types & Rates
pH & Solution Chemistry
200
What are isotopes?
Atoms of the same element with different numbers of neutrons
200
Which group is known as halogens?
Group 17
200
Which element is least likely to bond and why?
Noble gases; they are stable with full valence shells
200
What is a combustion reaction?
A reaction involving oxygen producing heat/light (typically CO₂ + H₂O)
200
What type of ions do bases release in water?
Hydroxide ions (OH⁻)
400
How do isotopes of the same element differ?
Different mass numbers
400
What group of metals is very reactive with water?
Alkali metals
400
What kind of atoms form covalent bonds?
Nonmetals with other nonmetals
400
What changes when a catalyst is added to a reaction?
It lowers activation energy, increasing reaction rate
400
What does it mean for a solution to be saturated?
It contains the maximum amount of dissolved solute
600
What happens to an atom’s mass in radioactive decay?
It decreases slightly as particles are emitted
600
Why is mercury used in thermometers?
Only liquid metal at room temperature
600
What bond involves partial charges due to unequal sharing?
Polar covalent bond
600
Which factors increase reaction rate?
Increased temperature, concentration, surface area, catalysts
600
How does temperature affect gas solubility in liquids?
It decreases
800
What are the products of alpha decay?
Helium nucleus: 2 protons + 2 neutrons
800
What trend occurs in atomic radius as you move down a group?
It increases
800
How many valence electrons are in CH₄?
8 total (4 from carbon, 1 from each hydrogen)
800
What reaction type involves two compounds swapping partners?
Double replacement
800
How does the pH scale relate to hydronium ion concentration?
Each number change = tenfold ion concentration difference
1000
What determines an atom’s average atomic mass?
Weighted average of all natural isotopes
1000
Why does fluorine have high electronegativity?
It strongly attracts electrons due to high nuclear charge and small size
1000
Draw or describe the Lewis structure of HCN.
Triple bond between C and N, single bond between H and C, 2 electrons on H, 8 total on C and N
1000
Describe an exothermic vs. endothermic reaction using an energy diagram.
Exothermic releases energy (product energy lower); endothermic absorbs energy (product energy higher)
1000
What is autoionization of water and its effect on pH?
Water molecules split into H⁺ and OH⁻ ions, maintaining equilibrium near pH 7