Matter, Measurement, Energy, and Gases
Name three states of matter and one characteristic of each.
Three states of matter are solid (definite shape and volume), liquid (definite volume but takes the shape of the container), and gas (no definite shape or volume).
What is a metal, and what happens to its electrons when it typically forms bonds with nonmetals?
A metal is typically a good conductor of heat and electricity and usually forms positive ions by losing electrons when bonding.
What is the difference between a synthesis and decomposition reaction?
A synthesis reaction combines two or more substances to form a new compound, while a decomposition reaction breaks down a compound into simpler substances.
What is the definition of a solute and solvent?
A solute is the substance dissolved in a solution, while a solvent is the substance that does the dissolving.
A saturated solution is at this when the rate of dissolving equals the rate of crystallization
Equilibrium
What is density and how is it calculated?
Density is calculated using the formula Density=mass/volume
What is the significance of the atomic number?
The atomic number is the number of protons in the nucleus of an atom, which determines the element's identity.
Define half-life and its importance in nuclear chemistry.
Half-life is the time required for half of a radioactive substance to decay, important for understanding the stability of isotopes.
How do you determine the concentration of an acid in a solution? (Hint: What kind of reaction can you carry out?)
You can carry out a titration (neutralization reaction) and utilize MAVA=MBVB
Describe how kinetic energy relates to temperature.
Kinetic energy relates to temperature as temperature is a measure of the average kinetic energy of the particles in a substance.
How do you convert Celsius to Kelvin?
To convert Celsius to Kelvin, add 273.15 (K=C+273.15K=C+273.15).
What are the main types of chemical bonds?
The main types of chemical bonds are ionic bonds (transfer of electrons), covalent bonds (sharing of electrons), and metallic bonds (sea of electrons).
How do you name ionic compounds?
Ionic compounds are named by stating the name of the cation first followed by the name of the anion (e.g., NaCl is sodium chloride).
What happens to the boiling point and freezing point of water with the addition of solute?
What is boiling point increases and freezing point decreases
Explain the factors that affect reaction rates.
Explain the difference between physical and chemical properties.
Physical properties can be observed without changing the substance (e.g., color, melting point), while chemical properties describe how a substance reacts to form new substances.
What is an isotope, and how does it differ from a regular atom?
An isotope is an atom with the same number of protons but a different number of neutrons, resulting in a different atomic mass.
Determine the decay mode and detail the transmutation equation for 198Au
Beta decay
198Au
4Al + 3O2 → 2Al2O3
How many moles of Al will be produced from 4 moles of O2?
5.33 moles
What is Le Chatelier's principle?
Le Chatelier's principle states that if a system at equilibrium is subjected to a change in concentration, temperature, or pressure, the system will adjust to counteract that change and restore equilibrium.
What is the ideal gas law, and how can it be expressed mathematically?
The ideal gas law is expressed as PV=nRT, where P is pressure, V is volume, n is the number of moles, R is the ideal gas constant, and T is temperature in Kelvin.
Describe the significance of the periodic law.
The periodic law states that the properties of elements are periodic functions of their atomic numbers, leading to the organization of elements in the periodic table.
What is the balanced equation for the combustion of methane (CH4)?
The balanced equation for the combustion of methane is
CH4+2O2→CO2+2H2O
NH3 + H2O ⇌ NH4+ + OH−
Identify the conjugate acid-base pairs in the reaction.
Explain how NH₃ acts as a base in this reaction.
NH₃ acts as a base because it accepts a proton (H⁺) from water, forming NH₄⁺. Water donates the proton, acting as an acid, and becomes OH⁻ in the process.
What happens to a system at equilibrium when stress is applied?
When stress is applied to a system at equilibrium, the system shifts in the direction that reduces the stress (e.g., decreasing pressure shifts the equilibrium to the side with more gas molecules).