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 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.
What is the difference between a synthesis and a 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 a solvent?
A solute is the substance dissolved in a solution, while a solvent is the substance that does the dissolving.
Explain the factors that affect reaction rates.
Factors that affect reaction rates include:
Temperature
Concentration
Surface area
Nature of reactants
Pressure (gases only)
The presence of catalysts
What is density and how is it calculated?
Density is calculated using the formula Density=mass/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.
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
Name the following compound: CH₃CH₂OH
Ethanol
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?
Boiling point increases and freezing point decreases
In the reaction Zn + CuSO₄ → ZnSO₄ + Cu, which element is oxidized and which is reduced?
Zinc is oxidized, and copper is reduced
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
According to Le Chatelier’s Principle, what happens to the equilibrium position when more reactant is added to a system at equilibrium?
The equilibrium shifts to the right (toward products)
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 trend of the following regarding the periodic table and what they are:
Ionization energy
Atomic radius
Electronegativity
1. Ionization Energy: The amount of energy required to remove an electron from an atom (usually the outermost electron).
Trend:
Increases across a period (left → right)
Decreases down a group (top → bottom)
2. Atomic Radius: The distance from the nucleus to the outermost electron of an atom (size of the atom).
Trend:
Decreases across a period (left → right)
Increases down a group (top → bottom)
3. Electronegativity: The ability of an atom to attract electrons in a chemical bond.
Trend:
Increases across a period (left → right)
Decreases down a group (top → bottom)
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.
This class of hydrocarbons contains only single bonds between carbon atoms, making them fully saturated with hydrogen. Name the class and provide its general molecular formula.
Alkanes, with the general formula CₙH₂ₙ₊₂