Flocabulary Atoms and Elements

The smallest unit of matter is a(n) (a)   .

• molecule

• atom

• covalent bond

• electron

Answer explanation

The smallest unit of matter is an atom, which consists of protons, neutrons, and electrons. Molecules are made of atoms, and covalent bonds are interactions between atoms. Electrons are subatomic particles, not units of matter.

Which are characteristics of all metals?

• Conductivity

• Malleability

• Ductility

• Luster

Answer explanation

All metals are characterized by conductivity and malleability. Conductivity allows them to transmit heat and electricity, while malleability enables them to be shaped without breaking.

Noble gases are known as (a)   .

• ionic gases

• inert gases

• metalloid gases

• ductile gases

Answer explanation

Noble gases are referred to as 'inert gases' because they are largely unreactive due to having a full valence shell of electrons. This stability makes them distinct from other types of gases.

The three main subatomic particles that make up an atom are (a)   .

• neutrons, protons and molecules

• neutrons, protons and ions

• ions, electrons and newtons

• electrons, neutrons and protons

Answer explanation

The three main subatomic particles that make up an atom are electrons, neutrons, and protons. The other options incorrectly include molecules, ions, or newtons, which are not fundamental particles of an atom.

Elements in a vertical column on the Periodic Table have similar properties and are all members of the same (a)   of elements.

• molecule

• phase

• atom

• group

Answer explanation

Elements in a vertical column of the Periodic Table are classified as a 'group' because they share similar chemical properties. This grouping reflects their similar valence electron configurations.

The number of protons in an atom is known as its atomic (a)   .

• number

• mass

• phase

• bond

Answer explanation

The atomic number of an atom is defined as the number of protons it contains. Therefore, the correct answer is 'number', as it directly relates to the protons in the atom.

When two or more elements are combined, the substance produced is a (a)   .

• suspension

• transitional metal

• compound

• noble gas

Answer explanation

When two or more elements chemically combine, they form a compound. This is distinct from a suspension, which is a mixture, and noble gases, which are individual elements. Transitional metals are also elements, not compounds.

Tags

NGSS.MS-PS1-1

The force of attraction that holds two atoms together within a molecule is (a)   .

• thermonuclear bonding

• chemical bonding

• crystal bonding

• an atomic number

Answer explanation

The force that holds two atoms together in a molecule is known as chemical bonding. This term encompasses various types of bonds, such as covalent and ionic bonds, which are essential for molecule formation.

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-3

An atom that has lost or gained an electron no longer has a neutral charge. We call this negatively or positively charged atom a(n) (a)   .

• Ion

• Atom

• Molecule

• Electron

Answer explanation

An atom that has lost or gained an electron becomes charged, resulting in an ion. A negatively charged ion is called an anion, while a positively charged ion is called a cation. Thus, the correct term is 'Ion'.

Tags

NGSS.MS-PS2-3

NGSS.MS-PS2-5

In a chemical reaction, two reactants mix. The resulting substance is called a(n) (a)   .

• ionic bond

• atomic bond

• product

• transitional metal

Answer explanation

In a chemical reaction, when two reactants mix, they form a new substance known as a product. This term specifically refers to the outcome of the reaction, distinguishing it from bonds or types of elements.