Font size
WorksheetsChapter 2: Atoms and Elements
Total questions: 91
Worksheet time: 46mins
What is the definition of an atom?
The smallest unit of an element that retains the properties of that element.
A large molecule made of many elements.
A type of chemical reaction.
The process of splitting elements.
Why must we begin with atoms when studying chemistry?
Because atoms are the fundamental building blocks of matter.
Because atoms are the largest particles in the universe.
Because atoms are only found in living things.
Because atoms are not important in chemistry.
Who was Robert Brown?
A scientist who first observed the random motion of particles in a fluid.
The inventor of the periodic table.
A famous chemist who discovered oxygen.
The first person to split an atom.
What is Brownian motion?
The random movement of particles suspended in a fluid.
The process of atoms bonding together.
The splitting of an atom.
The movement of electrons in an atom.
What did Einstein conclude was the actual cause of Brownian motion?
The movement of atoms and molecules colliding with particles.
The gravitational pull of the Earth.
The effect of sunlight on particles.
The presence of magnetic fields.
What is scanning tunneling microscopy?
A technique that allows scientists to visualize individual atoms on surfaces.
A method for splitting atoms.
A way to measure the mass of molecules.
A process for creating new elements.
How would you redefine an atom based on modern scientific understanding?
An atom is the smallest unit of matter that retains the identity of an element and consists of a nucleus surrounded by electrons.
An atom is a large molecule made of many elements.
An atom is a type of chemical reaction.
An atom is a process for creating new elements.
What is the definition of an element?
A substance that cannot be broken down into simpler substances by chemical means.
A mixture of two or more substances.
A substance that can be separated by physical means.
A compound made of different atoms.
What was the primary difference between the theories of the Greek philosophers and modern scientists regarding the building blocks of matter?
Greek philosophers relied on reasoning, while modern scientists use experimental evidence.
Greek philosophers used advanced technology, while modern scientists do not.
Modern scientists believe in magic, while Greek philosophers did not.
Greek philosophers performed experiments, while modern scientists only theorize.
What is the definition of atomic theory?
A theory that all matter is composed of atoms.
A theory that atoms are made of protons only.
A theory that atoms do not exist.
A theory that all matter is made of energy.
What does the Law of Conservation of Mass state?
Mass is neither created nor destroyed in a chemical reaction.
Mass can be created from nothing.
Mass is always lost in chemical reactions.
Mass is only conserved in physical changes.
What is the definition of the Law of Definite Proportions?
A chemical compound always contains the same elements in the same proportion by mass.
A chemical compound can have any proportion of elements.
Elements combine in random ratios to form compounds.
The mass of a compound is always greater than the sum of its elements.
What does the Law of Multiple Proportions state?
When two elements combine to form more than one compound, the masses of one element that combine with a fixed mass of the other are in the ratio of small whole numbers.
All matter is made up of atoms, which are indivisible and indestructible.
Atoms of the same element are identical in mass and properties.
Atoms can be subdivided, created, or destroyed in chemical reactions.
Which of the following is NOT one of the four parts of Dalton’s Atomic Theory?
All matter is made of indivisible atoms.
Atoms of different elements can combine in simple whole-number ratios to form compounds.
Atoms can be created or destroyed in chemical reactions.
Atoms of a given element are identical in mass and properties.
What is a cathode ray?
A stream of electrons observed in vacuum tubes.
A type of electromagnetic radiation.
A positively charged particle.
A form of visible light.
Which part of Dalton’s Atomic Theory explains why water (H₂O) and hydrogen peroxide (H₂O₂) are different substances?
Atoms of different elements can combine in simple whole-number ratios to form compounds.
All matter is made of indivisible atoms.
Atoms of a given element are identical in mass and properties.
Atoms cannot be subdivided, created, or destroyed.
If you were to evaluate a question at the end of a reading section, which skill would you be using?
Recall and reproduction
Strategic thinking
Simple calculation
Memorization only
What is the name of the negatively charged electrode in a cathode ray tube?
Cathode
Anode
Proton
Neutron
Which of the following is the positively charged electrode in a cathode ray tube?
Cathode
Anode
Electron
Neutron
Which of the following best defines "electrical charge"?
The region around a charged particle where a force is exerted
The property of matter that causes it to experience a force when placed in an electric or magnetic field
The flow of electrons through a conductor
The mass of a subatomic particle
What is an electric field?
The property of matter that causes it to experience a force
The region around a charged particle where a force is exerted on other charges
The flow of electrons through a wire
The total number of protons in an atom
Which of the following best describes an electron?
A positively charged subatomic particle
A neutral subatomic particle
A negatively charged subatomic particle
A particle with no mass
Which experiment was used to determine the charge of the electron?
Rutherford’s Gold Foil Experiment
Millikan’s Oil Drop Experiment
Thomson’s Cathode Ray Experiment
Bohr’s Hydrogen Spectrum Experiment
Which of the following is a characteristic of the particles Thomson explored in the cathode ray?
They are positively charged
They have mass and are negatively charged
They are neutral
They are only found in metals
What is the Coulombic charge of an electron?
+1.602 x 10^-19 C
0 C
-1.602 x 10^{-19} C
-9.109 x 10^{-31} C
What is the mass of an electron?
1.672 x 10^{-27} kg
9.109 x 10^{-31} kg
1.602 x 10^{-19} kg
1.008 x 10^{-24} kg
Why is it important to know the charge of the electron?
It helps determine the color of the atom.
It is necessary for understanding atomic structure and chemical reactions.
It is used to calculate the speed of light.
It determines the melting point of elements.
How did scientists know there must be other charged particles in an atom?
Atoms were found to be neutral overall, suggesting the presence of positive charges to balance electrons.
Atoms glowed in the dark.
Atoms could be seen under a microscope.
Atoms were magnetic.
What is the Plum Pudding Model (Americanized Blueberry Muffin Model)?
Atoms are made of a dense nucleus surrounded by electrons.
Atoms are solid spheres.
Atoms consist of electrons scattered within a positively charged "pudding" or matrix.
Atoms are made only of protons.
What is radioactivity?
The emission of energy as electromagnetic waves.
The spontaneous emission of particles or energy from unstable atomic nuclei.
The absorption of light by atoms.
The process of atoms combining to form molecules.
What are the three types of radioactivity and what makes one of them special?
Alpha, beta, and gamma; gamma is special because it is a form of electromagnetic radiation.
Alpha, delta, and epsilon; delta is special because it is the heaviest.
Beta, gamma, and theta; theta is special because it is invisible.
Alpha, beta, and omega; omega is special because it is the fastest.
Describe Rutherford’s Gold Foil Experiment.
Electrons were discovered by passing electricity through gold foil.
Alpha particles were shot at gold foil, and most passed through, but some were deflected, showing the atom has a small, dense nucleus.
Gold foil was melted to observe atomic structure.
Protons were extracted from gold foil using magnets.
Which of the following is NOT one of the three basic parts of The Nuclear Theory?
Most of the atom's mass and all of its positive charge are contained in a small core called the nucleus.
Most of the volume of the atom is empty space, through which tiny, negatively charged electrons are dispersed.
The number of protons in the nucleus is equal to the number of neutrons.
The atom is electrically neutral because the number of protons equals the number of electrons.
What was missing from the Rutherford model of the atom?
The existence of electrons
The explanation of atomic mass
The arrangement of electrons in the atom
The presence of protons in the nucleus
How is an atom like a cloud?
It is made of water vapor.
Its electrons are spread out in a region around the nucleus, similar to how a cloud is spread out in the sky.
It is always moving.
It is visible to the naked eye.
If matter is mostly empty space, why do most things appear solid?
Because atoms are packed tightly together with no space between them.
Because the electrons in atoms repel each other, preventing atoms from passing through one another.
Because the nucleus is very large.
Because atoms are made of solid material.
What is the definition of an Atomic Mass Unit (amu)?
The mass of a single proton or neutron, approximately 1/12 the mass of a carbon-12 atom.
The total number of protons and electrons in an atom.
The number of atoms in one mole of a substance.
The energy required to remove an electron from an atom.
Which subatomic particle has a relative charge of +1?
Proton
Neutron
Electron
Photon
What is the relative charge of an electron?
-1
0
+1
+2
Which subatomic particle has a mass of approximately 1 amu and no charge?
Neutron
Proton
Electron
Photon
How are elements defined?
By their atomic number
By their mass number
By their chemical symbol
By their natural abundance
What does the atomic number (Z) represent in an atom?
The number of protons in the nucleus
The number of neutrons in the nucleus
The total number of protons and neutrons
The number of electrons in the outer shell
Which of the following best defines isotopes?
Atoms of the same element with different numbers of neutrons
Atoms of different elements with the same number of protons
Atoms with the same mass number but different atomic numbers
Atoms with the same number of electrons but different charges
What does the chemical symbol of an element represent?
A one- or two-letter abbreviation for an element
The number of protons in the nucleus
The mass number of the element
The natural abundance of the element
What is natural abundance?
The percentage of a particular isotope found in nature
The total number of protons in an atom
The mass of an atom in atomic mass units
The charge of an electron
What does the mass number (A) of an atom represent?
The total number of protons and neutrons in the nucleus
The number of protons in the nucleus
The number of electrons in the atom
The atomic number of the element
If X is used to represent a chemical element, what does X stand for?
The chemical symbol of the element
The atomic number of the element
The mass number of the element
The natural abundance of the element
Which of the following best defines an ion?
An atom or molecule with a net electric charge due to the loss or gain of one or more electrons.
An atom with the same number of protons and neutrons.
A molecule made up of only one type of atom.
An atom that has lost all of its electrons.
What is a cation?
An atom or molecule that has gained electrons and has a negative charge.
An atom or molecule that has lost electrons and has a positive charge.
An atom with no charge.
An atom with more neutrons than protons.
Which of the following describes an anion?
An atom or molecule that has lost electrons and has a positive charge.
An atom or molecule that has gained electrons and has a negative charge.
An atom with equal numbers of protons and electrons.
An atom with more protons than electrons.
Which of the following statements is true about isotopes of Neon?
They have the same number of protons but different numbers of neutrons.
They have different numbers of protons and the same number of neutrons.
They have the same number of electrons but different numbers of protons.
They have different numbers of electrons and neutrons.
Which of the following is an alternate way to express the common notation for Neon isotopes?
Ne-20, Ne-21, Ne-22
N-14, N-15, N-16
O-16, O-17, O-18
C-12, C-13, C-14
Do ions and their representative elements have similar behaviors?
Yes, they always behave the same way in all reactions.
No, ions and their representative elements never have similar behaviors.
Yes, ions often have similar chemical behaviors to their representative elements.
Ions and their representative elements are unrelated in behavior.
What is the Periodic Law?
The law that states all elements are metals.
The law that properties of elements are periodic functions of their atomic numbers.
The law that elements are arranged alphabetically.
The law that all elements have the same number of protons.
How is the modern Periodic Table organized?
By alphabetical order of element names.
By increasing atomic mass.
By increasing atomic number.
By color of the elements.
Where would you find metals on the periodic table and what is a characteristic property of metals?
On the right side; they are poor conductors of electricity.
In the center and left side; they are good conductors of heat and electricity.
On the top row; they are gases at room temperature.
On the bottom row; they are always liquids.
Where are non-metals typically found on the periodic table and what is a characteristic property?
On the left side; they are shiny and malleable.
On the right side; they are poor conductors of heat and electricity.
In the center; they are ductile.
On the bottom; they are always solid.
What is a characteristic property of metalloids and where are they found on the periodic table?
They are found in the center and are good conductors.
They are found along the stair-step line and have properties of both metals and non-metals.
They are found on the far right and are gases.
They are found on the far left and are always liquid.
What is a semiconductor?
A material that does not conduct electricity at all.
A material that conducts electricity better than metals.
A material that has conductivity between that of metals and non-metals.
A material that is always a gas.
What is a main-group element?
An element found only in the transition metals section.
An element in the s and p blocks of the periodic table.
An element that is always radioactive.
An element that is only found in nature.
What is a transition element?
An element found in the d-block of the periodic table
An element that is always a gas at room temperature
An element that is only found in nature
An element that does not react with other elements
What is a family in the context of the periodic table?
A row of elements
A group of elements with similar chemical properties
A single element
A type of chemical bond
What is a group in the periodic table?
A column of elements
A row of elements
A set of isotopes
A type of molecule
Which of the following is an alkali metal?
Sodium
Calcium
Chlorine
Helium
Which of the following is an alkaline earth metal?
Magnesium
Potassium
Oxygen
Neon
Which of the following is a halogen?
Fluorine
Iron
Lithium
Argon
Which of the following is a noble gas?
Neon
Sodium
Bromine
Calcium
What tends to happen in chemical reactions with metals?
They tend to lose electrons
They tend to gain electrons
They do not react
They form covalent bonds only
What tends to happen in chemical reactions with nonmetals?
They tend to gain electrons
They tend to lose electrons
They always form metallic bonds
They do not react
What are the identified trends of main-group metals?
They become more reactive as you go down a group
They become less reactive as you go down a group
They do not show any trends
They always form gases
What are the identified trends of the main-group nonmetals?
They tend to lose electrons easily.
They are generally good conductors of electricity.
They tend to gain electrons and form negative ions.
They are always found in metallic form.
Which of the following is a common charge associated with Group 1A elements?
+2
-1
+1
0
What is unique about the transition metals and the charges they form?
They only form one type of charge.
They can form multiple positive charges.
They do not form ions.
They always form negative charges.
How was Dalton’s Theory incorrect?
Dalton stated that atoms are indivisible, but atoms can be divided into subatomic particles.
Dalton believed all atoms of an element are different, but they are actually identical.
Dalton claimed atoms can be created or destroyed in chemical reactions.
Dalton said atoms have a fixed shape.
What does the atomic mass found on the Periodic Table represent for each element?
The number of protons only.
The average mass of all the isotopes of that element.
The number of electrons in the outer shell.
The mass of the most common isotope only.
What is the formula for atomic mass?
Atomic mass = Number of protons + Number of electrons
Atomic mass = Number of neutrons + Number of electrons
Atomic mass = (Fractional abundance × Isotope mass) summed for all isotopes
Atomic mass = Number of protons × Number of neutrons
What is the definition of mass spectrometry?
A technique used to measure the mass and abundance of atoms or molecules
A method for measuring temperature changes in reactions
A process for separating liquids based on boiling points
A technique for measuring electrical conductivity
In mass spectrometry, what does "intensity" refer to?
The brightness of the light emitted by a sample
The number of ions detected at a specific mass-to-charge ratio
The speed at which ions travel through the instrument
The amount of energy required to ionize a sample
What does "total intensity" mean in the context of mass spectrometry?
The sum of all detected ion signals across all mass-to-charge ratios
The highest peak in the mass spectrum
The energy required to ionize all atoms in a sample
The number of atoms present in a sample
What does "abundance" refer to in mass spectrometry?
The relative amount of a specific ion compared to the total ions detected
The total number of atoms in a sample
The energy required to break chemical bonds
The speed of ion movement in the instrument
Can we count individual atoms? Why or why not?
No, because atoms are too small to be counted individually with current technology
Yes, because atoms are large enough to be seen with the naked eye
Yes, because we can use a balance to count them directly
No, because atoms do not exist in measurable quantities
What is the definition of a mole in chemistry?
A unit that represents 6.022x1023 particles of a substance
A unit of mass equal to one gram
A measure of temperature
A type of chemical reaction
What is Avogadro’s number?
6.022 x 10^23
1.602x10−19
3.14
9.81
What are the two conversion factors for converting between the number of moles and the number of atoms?
Avogadro’s number and its reciprocal
Molar mass and density
Volume and pressure
Temperature and energy
What is the definition of molar mass?
The mass of one mole of a substance, usually expressed in grams per mole
The number of atoms in a molecule
The volume occupied by one mole of a substance
The energy required to remove an electron from an atom
What is the conceptual plan when counting the number of atoms in a sample by weighing?
Measure the mass of the sample, convert mass to moles using molar mass, then convert moles to number of atoms using Avogadro's number
Count the atoms directly under a microscope
Measure the volume and divide by the atomic volume
Use the color of the sample to estimate the number of atoms
What is the conceptual plan to determine the mass of a particular number of atoms?
Convert the number of atoms to moles using Avogadro's number, then convert moles to mass using molar mass
Weigh each atom individually and add the masses
Estimate the mass based on the color of the atoms
Use the density of the substance to find the mass
Which of the following is NOT typically used as a conversion factor when performing calculations involving the properties of substances?
Mole Mass
Avogadro’s Number
Density
Atomic Radius
What is the primary purpose of combining different types of calculations, such as using density and information from the periodic table, in chemistry?
To memorize the periodic table
To obtain information that may not be immediately obvious
To avoid using conversion factors
To simplify the periodic table
If you are given the density of a substance and need to find the radius of a sphere of that substance, which of the following conceptual steps would you most likely use?
Use the density to find the mass, then use the mass to find the volume, and finally use the volume to find the radius.
Use the density to find the radius directly.
Use the periodic table to find the radius.
Use Avogadro’s number to find the radius directly.
Why is it important to write the conversion factor underneath each arrow in a conceptual plan for a calculation?
To show the units being converted at each step
To make the calculation more difficult
To avoid using the periodic table
To skip unnecessary steps
