Quiz 3: Atoms, Molecules, and Ions

The smallest piece of an element that maintains the identity of that element is called a molecule.

The proton is a heavier subatomic particle than the electron and has a positive charge.

The number of protons and electrons in an element's nucleus is called the atomic number of the element.

Atoms of the same element with different numbers of electrons are called isotopes.

'Au' is the atomic symbol of the element silver.

Uranium-235 isotope of uranium has 143 neutrons.

Hydrogen and oxygen exist naturally as three-atom molecules.

The connection between two atoms in a molecule is called a chemical bond.

According to chemical nomenclature, SO₂ is referred to as sulfur dioxide.

The molecule Se₂Br₂ is called diselenide dibromide.

The atomic mass unit is defined as one-twelfth of the mass of a nitrogen-14 atom.

The atomic mass of an element is a weighted average of the masses of the isobars of an atom.

The molecular mass of dinitrogen trioxide is determined by adding the atomic mass of nitrogen two times with the atomic mass of oxygen three times.

Species with overall negative charges are termed anions.

Monatomic ions are formed when an atom loses or gains one or more electrons to attain a charge.

I⁻ is an example of a monatomic anion.

N³⁻ is called trinitride ion.

A proper covalent formula has a cation and an anion in it.

In the ionic compound NaCl, sodium ion is the cation and chloride ion is the anion.

According to the nomenclature of ionic compounds, MgCl₂ is called magnesium dichloride.

Fe₂S₃ is called iron(II) sulfide.

Atoms that contain more than one unit charge are called polyatomic ions.

An acid is an ionic compound of the H⁺ cation dissolved in water.

If a compound is composed of hydrogen ions and a polyatomic anion, then the name of the acid is derived from the stem of the polyatomic ion's name.

HCl is the formula for chloric acid.

The smallest piece of an element that maintains the identity of that element is called a(n) _____. A) compound B) molecule C) atom D) ingredient E) particle

Which of the following statements is consistent with the modern atomic theory? A) Atoms of different elements can have the same configuration. B) Atoms combine in whole number ratios to form compounds. C) All matter is composed of isotopes. D) Atoms of the same element are not the same always. E) An electron is smallest piece of an element that maintains its identity.

Which of the following is a tiny subatomic particle with a negative charge? A) Electron B) Proton C) Neutron D) Photon E) Isotope

The _____ is a relatively massive subatomic particle with a positive charge. A) isotope B) proton C) neutron D) nucleus E) electron

Identify the subatomic particle with about the same mass as a proton but no charge. A) Neutron B) Nucleus C) Electron D) Isotope E) Isobar

What is the approximate mass of a neutron, in kg? A) 6.6 × 10⁻²⁷ B) 9.1× 10⁻²⁸ C) 1.6 × 10⁻²⁷ D) 9.1 × 10⁻³¹ E) 1.6 × 10⁻³¹

The nucleus is made up of what two subatomic particles? A) Proton and electron B) Proton and neutron C) Neutron and electron D) Photon and electron E) Photon and neutron

Which of the following is an atom that is not a diatomic molecule? A) Helium B) Hydrogen C) Chlorine D) Fluorine E) Oxygen

The atomic number of an atom refers to the _____. A) number of protons in the atom B) the atomic mass of the nucleus C) the total mass of the electrons D) number of neutrons in the atom E) the atomic mass of the atom

The sum of the number of protons and neutrons in a nucleus is referred to as the _____ number. A) potential B) elemental C) atomic D) magnetic E) mass

Two atoms that have the same number of protons with different numbers of neutrons are called _____. A) nuclear isomers B) isotopes C) isotones D) isobars E) chemical isobars

The number of protons in the nucleus of an atom is 80, while the number of neutrons in the nucleus is 90. What is the mass number of this isotope? A) 10 B) 170 C) 80 D) 90 E) 135

Hg is the atomic symbol of the element _____. A) nickel B) helium C) gallium D) mercury E) germanium

Which of the following is the atomic symbol of gold? A) Gl B) Gd C) An D) Ga E) Au

Which of the following combinations refer to an isotope? A) and B) and C) and D) and E) and

How many neutrons can be found in the atom ? A) 43 B) 161 C) 118 D) 75 E) 32

Substances that exist as two or more atoms connected together so strongly that they behave as a single particle are called _____. A) compounds B) polyatoms C) diatomic compounds D) subatomic compounds E) molecules

Which of the following is not true in regards to sulfur hexafluoride (SF₆)? A) It has similar physical properties in the vapor phase as sarin B) It is very to detect C) It is not a normal part of the atmosphere D) Used as an aerial tracer for ventilation systems E) It is toxic and highly reactive

Hydrogen exists as molecules with _____ atom(s). A) seven B) two C) four D) four E) five

A chemical bond is a connection between _____. A) two molecules of a compound B) electrons and the nucleus of an atom C) two atoms in a molecule D) neutrons and protons in the nucleus E) two or more subatomic particles

What is the molecular formula of elemental hydrogen? A) H₂ B) H₄ C) H₅ D) H₆ E) H₈

Which of the following is name given to SO₂ according to chemical nomenclature? A) Sulfur oxide B) Oxo-sulfur C) Sulfur dioxide D) Sulfo-oxide E) Dioxy sulfide

Which of the following represents diphosphorus hexafluoride? A) (PF₃)₆ B) P₂F₄ C) P₂FO₆ D) P₂F₆ E) P₂O₂F₆

Which of the following constitute a proper molecule? A) Cl B) H₂O C) N D) P⁺ E) O^-

The mass of an electron is _____ atomic mass units. A) 1.00728 B) 0.000549 C) 0.5490 D) 1.879 E) 1.866

The _____ of an element is a weighted average of the masses of the isotopes that compose an element. A) atomic number B) mass number C) isotopic mass D) atomic mass E) nuclear mass

Uranium exists as about 98% U-238 and about 2% U-235. What is the atomic mass of uranium? A) 238.06 B) 237.94 C) 237.14 D) 238.86 E) 239.55

The molecular mass is the sum of _____ in a molecule. A) redundant neutrons B) masses of subatomic particles C) masses of protons D) the masses of the atoms E) electronic masses of atoms

What is the atomic mass of dinitrogen trioxide (atomic mass of oxygen=15.999 u; atomic mass of nitrogen = 14.007 u)? A) 76.011 u B) 30. 010u C) 74.019u D) 160.012u E) 60.019u

Electrons move from one atom to another to form species with overall electric charges. Such species are called _____. A) beams B) antiparticles C) ions D) quarks E) composite particles

Species with overall positive charges are termed _____. A) quarks B) beams C) cations D) anions E) antiparticles

Which of the following is an example of an anion formed by the gain of two electrons? A) Br⁻ B) Cu²⁺ C) Na⁺ D) Se²⁻ E) Rb⁺ I^-

The Cl⁻ ion is formed when a chlorine atom _____. A) loses one electron B) gains one electron C) loses one proton D) gains one proton E) gains one proton and loses one electron

Which of the following represents the sodium ion? A) Na²⁺ B) Na⁺ C) NaO^- D) Na⁺OH^- E) Na^2-

Which of the following terms represents the species O^2-? A) oxide anion B) oxide cation C) oxygen anion D) oxygen cation E) oxo-cation

Write the proper ionic formula for the ionic compound obtained from the ions Al³⁺ and F⁻. A) Al₃F₃ B) (AlF)₃ C) AlF D) Al₃F E) AlF₃

Ionic compounds form between: A) metals and metals. B) nonmetals and nonmetals C) semiconductors and carbon alloys D) metals and nonmetals. E) semiconductors and nonmetals

Polyatomic ions are a group of ions that _____. A) have same mass number and different atomic numbers B) contain more than one atom C) contain more than one positive or negative charge D) have same atomic number and different mass numbers E) contain more than one electron

Which of the following species is called sodium nitrate? A) NaNO₂ B) Na₅N C) Na₃NOH D) Na₂NO E) NaNO₃

Which of the following polyatomic ions is a cation? A) Bicarbonate B) Carbonate C) Chlorate D) Peroxide E) Ammonium

Which of the following polyatomic ions is an oxyanion? A) Triiodide B) Cyanide C) Ammonium D) Carbonate E) Calcium ion

Common table salt (sodium chloride), used on foods, is the ionic compound _____. A) NaCl₂ B) SoCl₂ C) SoCl D) NaCl E) Na₂Cl₂

An acid is an ionic compound of the _____ dissolved in water. A) K⁺ cation B) H⁺ cation C) O^- anion D) Na⁺ cation E) OH^- anion

Which of the following represents acetic acid? A) HC₂H₃O₂ B) H₂C₂O₄ C) HClO₄ D) H₃PO₄ E) H₂SO₃

Which of the following statements is true for all acids? A) Acids do not react with metals. B) Acids do not contain nitrogen. C) Acids have a sour taste. D) Acids do not contain oxygen. E) Acids do not contain water.

The _____ is a subatomic particle with about the same mass as a proton but no charge.

Atoms of the same element with different numbers of neutrons are called _____.

The magnitude of the charge is listed as a right _____ next to the symbol of the element.

The smallest part of a substance that has the physical and chemical properties of that substance is called a(n) _____.

The connection between two atoms in a molecule is known as a(n) _____.

_____ is a specific system for naming compounds, in which unique substances get unique names.

The _____ of an element is a weighted average of the masses of the isotopes that compose an element.

The _____ is the sum of the masses of the atoms in a molecule.

_____ is the proper name for the ionic compound formed between the ions K⁺ and S²⁻.

A species with an overall positive charge is called a(n) _____.

Species with an overall negative charge are called _____.

A compound formed from positive and negative ions is called a(n) _____.

An ion that contains more than one atom is called a(n) _____.

A(n) _____ is an ionic compound of the H⁺ cation dissolved in water.

Hydrochloric acid can be represented by the formula _____.

Explain the major postulates of modern atomic theory.

What is an atom? What are subatomic particles?

What are isotopes? Provide two examples.

What is a molecule? Provide examples of elements that exist naturally as molecules.

State and explain the rules of chemical nomenclature with an example.

What is atomic mass unit? What are the masses of subatomic particles when expressed in this unit?

Explain how atomic mass of an element is calculated with an example.

What is the molecular mass of a molecule? How is it calculated? Provide an example.

What are ions? What are the two types of ions?

What are ionic compounds? Provide two examples.

How are monatomic ions formed? Provide examples.

Explain the formation of an ionic compound between Mg²⁺ ions and Cl⁻ ions.

How do you name binary molecular compounds? Explain with two examples.

Explain the terms polyatomic ions and oxyanions.

What are acids? Explain their nomenclature.