Introduction to Chemistry

Which statement best differentiates between physical and chemical properties?

A chemist performs an experiment to determine the rate of a reaction and the energy transferred during the process. Which branch of chemistry is most relevant to this experiment?

Consider a scenario where iron is exposed to oxygen and water, resulting in rust formation. Which of the following best describes the type of change and the property demonstrated?

A scientist is analyzing a sample of ocean water. After thorough testing, they identify the presence of water ($H_2O$), sodium chloride ($NaCl$), and magnesium sulfate ($MgSO_4$). How should this sample be classified?

In a laboratory experiment, four students independently measure the mass of a copper sample. Their results are 5.45g, 5.46g, 5.45g, and 5.46g. The actual mass of the copper is known to be 5.65g. How would you describe the measurements?

Which subatomic particles contribute significantly to the mass of an atom?

Suppose a chemist discovers a new element. They find that it readily combines with highly reactive nonmetals but does not react with noble gasses. This element is most likely a:

Consider two separate beakers. Beaker A contains a solution of sugar dissolved in water where the sugar is evenly distributed throughout. Beaker B encompasses sand mixed with iron fillings with visible layers. If 'A' is a homogeneous mixture, what mixture is 'B'?

Consider a scenario where a chemist is synthesizing a novel compound. The reaction involves multiple steps, each with varying yields. To optimize the overall yield, which strategy should the chemist prioritize, considering the principles of stoichiometry and limiting reactants?

In the context of chemical kinetics, a reversible reaction is at equilibrium. A chemist introduces an inert gas into the reaction vessel, maintaining constant volume. How will this affect the equilibrium, assuming the reaction involves gases?

A researcher is studying the dissolution of a sparingly soluble salt in water. Under what conditions would the salt's solubility be least affected, considering the principles of solution chemistry and equilibrium?

In a complex biochemical pathway, an enzyme-catalyzed reaction is found to have a Gibbs Free Energy change ($\Delta G$) close to zero. What does this indicate about the reaction under physiological conditions?

Two isotopes of the same element are analyzed using mass spectrometry. One isotope is more abundant. How does this difference in abundance primarily affect the macroscopic properties of a sample of this element?

A chemist dissolves a weak acid in water. Which of the following changes will lead to the smallest increase in the concentration of hydrogen ions ($H^+$)?

A metallic element is observed to have high electrical conductivity. According to bonding theories, what is the primary reason for this property?

Consider a chemical reaction in a closed system that has reached equilibrium. According to Le Chatelier's Principle, which of the following changes would not shift the equilibrium position?

When titrating a polyprotic acid ($H_3A$) with a strong base, multiple equivalence points are observed. What is the predominant species present in the solution at a point exactly halfway between the first and second equivalence points?

Two different voltaic cells are constructed under standard conditions. Cell 1 has a large positive cell potential, while Cell 2 has a small positive cell potential. What can be correctly inferred about these cells?

Chemistry

Matter

Physical Property

Chemical Property

Physical Change

Chemical Change

Element

Mixture

Atomic Number

Groups (Families)

Ionic Bond

Balancing Chemical Equations

Avogadro's Number

Limiting Reactant

Solution

pH scale

Catalyst

Entropy (S)