Introduction to Chemistry

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to Lesson

Podcast

Play an AI-generated podcast conversation about this lesson
Download our mobile app to listen on the go
Get App

Questions and Answers

Which of the following is an example of a chemical change?

  • Boiling water for tea.
  • Iron rusting. (correct)
  • Dissolving sugar in water.
  • Melting ice cream.

What is the main difference between a homogeneous and a heterogeneous mixture?

  • Homogeneous mixtures contain only one substance, while heterogeneous mixtures contain multiple substances.
  • Homogeneous mixtures can only be separated chemically, while heterogeneous mixtures can be separated physically.
  • Homogeneous mixtures have a uniform composition throughout, while heterogeneous mixtures do not. (correct)
  • Homogeneous mixtures are always liquids, while heterogeneous mixtures are always solids.

Which of the following best describes the 'Law of Conservation of Mass'?

  • Mass is always gained during a chemical reaction.
  • The total mass of reactants equals the total mass of products in a chemical reaction. (correct)
  • The mass of each element in a compound is constant and does not change.
  • Mass is always lost during a chemical reaction.

What distinguishes an element from a compound?

<p>An element cannot be broken down into simpler substances by chemical means, while a compound can. (D)</p> Signup and view all the answers

How do isotopes of the same element differ?

<p>They have a different number of neutrons. (A)</p> Signup and view all the answers

In a redox reaction, if a substance is oxidized, what happens to it?

<p>It loses electrons. (C)</p> Signup and view all the answers

What is the role of a limiting reactant in a chemical reaction?

<p>It determines the amount of product that can be formed. (C)</p> Signup and view all the answers

Which of the following is an example of an intensive property?

<p>Temperature (B)</p> Signup and view all the answers

What does the term 'molarity' represent in chemistry?

<p>Moles of solute per liter of solution. (D)</p> Signup and view all the answers

In the scientific method, what is the role of a hypothesis?

<p>It is a tentative explanation for a set of observations. (C)</p> Signup and view all the answers

Which type of radiation has a positive charge and is comprised of particles?

<p>Alpha particles (A)</p> Signup and view all the answers

What is the main characteristic of an alkane?

<p>It contains only carbon-carbon single bonds. (D)</p> Signup and view all the answers

Which of these is an example of a physical property?

<p>Odor (C)</p> Signup and view all the answers

What does the 'Law of Multiple Proportions' state?

<p>When two elements form more than one compound, the masses of one element that combine with a fixed mass of the other are in a ratio of small whole numbers. (A)</p> Signup and view all the answers

What type of compound is generally formed between nonmetals only?

<p>Covalent compound (C)</p> Signup and view all the answers

In terms of chemical nomenclature, what is a binary compound?

<p>A compound containing exactly two different elements. (D)</p> Signup and view all the answers

What is the purpose of balancing chemical equations?

<p>To comply with the law of conservation of mass. (B)</p> Signup and view all the answers

In a titration, what is the equivalence point?

<p>The point at which the number of moles of acid equals the number of moles of base. (D)</p> Signup and view all the answers

What is the primary characteristic of an alcohol in organic chemistry?

<p>Presence of a hydroxyl group (OH). (C)</p> Signup and view all the answers

If a student performs a chemical reaction and obtains less product than calculated, what term describes the calculated maximum amount of product?

<p>Theoretical Yield (C)</p> Signup and view all the answers

Flashcards

Chemistry

The study of matter and its properties, including how matter changes.

Matter

Anything that has mass and takes up space (volume).

Property (of matter)

A characteristic that allows us to recognize and distinguish different types of matter.

Pure Substance

Matter with distinct properties and a composition that doesn't vary.

Signup and view all the flashcards

Element

A substance that cannot be broken down into simpler substances.

Signup and view all the flashcards

Compound

A combination of two or more elements.

Signup and view all the flashcards

Mixture

Combinations of two or more substances where each retains its identity.

Signup and view all the flashcards

Homogeneous Mixture

Uniform mixtures throughout.

Signup and view all the flashcards

Heterogeneous Mixture

Non-uniform mixtures throughout.

Signup and view all the flashcards

Physical Property

A property observed without changing the substance's identity.

Signup and view all the flashcards

Chemical Property

A property describing how a substance changes to form other substances.

Signup and view all the flashcards

Intensive Properties

Properties that don't depend on the amount of substance.

Signup and view all the flashcards

Extensive Properties

Properties that depend on the quantity of the substance.

Signup and view all the flashcards

Physical Change

Change in appearance but not composition.

Signup and view all the flashcards

Chemical Change

Transformation of one or more substances into different substances.

Signup and view all the flashcards

Hypothesis

A tentative explanation for a set of observations.

Signup and view all the flashcards

Atom

Smallest quantity of an element that retains its chemical properties.

Signup and view all the flashcards

Protons

Positively charged particles in the nucleus.

Signup and view all the flashcards

Isotopes

Atoms with the same atomic number, but different mass numbers.

Signup and view all the flashcards

Cations

Ions with a positive charge.

Signup and view all the flashcards

Study Notes

  • Chemistry examines matter, its properties, and changes it undergoes.
  • Matter possesses mass and occupies volume.
  • Properties are characteristics that help identify and distinguish types of matter.
  • The common states of matter include gas, liquid, and solid.
  • Gases lack fixed volume or shape, adapting to their container.
  • Liquids have a definite volume but no specific shape.
  • Solids have both a definite shape and volume.
  • Pure substances have distinct properties and consistent composition.
  • Substances are classified as either elements or compounds.
  • Elements consist of only one type of atom.
  • Compounds are combinations of two or more elements.
  • Mixtures combine two or more substances, each retaining its chemical identity.
  • Each substance in a mixture is a component of the mixture.
  • Homogeneous mixtures exhibit uniform composition throughout.
  • Heterogeneous mixtures do not have a uniform composition.
  • Physical properties are observed without altering the substance's identity or composition.
  • Chemical properties describe how a substance changes or reacts to form other substances.
  • Intensive properties are independent of the amount of substance (e.g., temperature, melting point).
  • Extensive properties depend on the amount of substance (e.g., mass, volume).
  • A physical change alters a substance's appearance but not its composition.
  • A chemical change transforms one or more substances into new substances.
  • The scientific method is a structured research approach.
  • A hypothesis is a preliminary explanation for observations.
  • A theory is a unifying principle explaining facts and related laws.
  • Scientific laws are concise statements or equations about fundamental natural relationships.
  • Exact numbers have precisely known values.
  • Measured quantities include inexact numbers.
  • Precision reflects the agreement among individual measurements.
  • Accuracy indicates how closely measurements agree with the true value.
  • Dimensional analysis carries units through calculations.
  • Conversion factors change units.
  • Matter consists of atoms.
  • An atom is the smallest unit of an element retaining its chemical properties.
  • Elements cannot be broken down into simpler substances.
  • The law of constant composition states that a pure compound's elemental composition is consistent regardless of origin.
  • Chemical formulas show elements in a compound and their relative atomic numbers.
  • The law of conservation of mass: total mass remains constant during a chemical process.
  • The law of multiple proportions states that if elements A and B form multiple compounds, the masses of B that combine with A are in small whole number ratios.
  • Radioactivity involves spontaneous emission of radiation.
  • Alpha (α) particles are positively charged.
  • Beta (β) particles are negatively charged, like electrons.
  • Gamma (γ) rays are high-energy radiation.
  • The nuclear model features a small, dense, positively charged nucleus, with electrons outside.
  • The nucleus contains protons and neutrons.
  • Protons are positive, neutrons are neutral, and electrons are negative.
  • Atoms are neutral, containing equal protons and electrons.
  • The atomic number is the number of protons in an atom's nucleus.
  • The mass number is the total number of protons and neutrons.
  • Isotopes have the same atomic number but different mass numbers.
  • Chemical compounds result from chemical combinations of atoms.
  • Ionic compounds typically form between metals and nonmetals.
  • Covalent compounds generally form between nonmetals.
  • Ions are charged particles formed by electron gain or loss.
  • Cations are positive ions.
  • Anions are negative ions.
  • Polyatomic ions consist of multiple atoms.
  • Chemical nomenclature is the system of naming substances.
  • Binary compounds contain two elements.
  • Organic chemistry studies carbon compounds, mainly with hydrogen.
  • Hydrocarbons contain only carbon and hydrogen.
  • Alkanes are hydrocarbons with single bonds only.
  • Alcohols are organic compounds with a hydroxyl (OH) group.
  • Ethers contain two hydrocarbon groups bonded to an oxygen atom.
  • Carboxylic acids are organic acids with a carboxyl (COOH) group.
  • Chemical reactions rearrange atoms/molecules into new substances.
  • Chemical equations show reactant and product identities and quantities.
  • Balancing chemical equations ensures equal atom numbers on both sides.
  • Stoichiometry studies quantitative relationships in chemical reactions.
  • Coefficients in balanced equations indicate mole ratios of reactants/products.
  • The limiting reactant is fully consumed in the reaction.
  • Theoretical yield is the maximum product amount based on stoichiometry.
  • Actual yield is the product amount obtained from a reaction.
  • Percent yield relates actual yield to theoretical yield.
  • Solutions are homogeneous mixtures.
  • The solvent is the substance present in the largest amount.
  • Solutes are substances in smaller amounts.
  • Molarity (M) is moles of solute per liter of solution.
  • Electrolytes dissociate into ions in water.
  • Nonelectrolytes do not dissociate into ions in water.
  • Acids increase H+ concentration in aqueous solutions.
  • Bases increase OH- concentration in aqueous solutions.
  • Titration reacts a solution of known concentration with one of unknown concentration.
  • The equivalence point in titration is where moles of acid equal moles of base.
  • Redox reactions transfer electrons between substances.
  • Oxidation is the loss of electrons.
  • Reduction is the gain of electrons.
  • Oxidation numbers track electron transfer in redox reactions.
  • The oxidizing agent causes oxidation and is reduced.
  • The reducing agent causes reduction and is oxidized.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Quiz Team
Use Quizgecko on...
Browser
Browser