If only an element’s atomic number and weight are provided, what other atomic information can be determined for a neutral atom?
only the number of protons and electrons
only the number of protons and electrons
the number of protons, electrons and neutrons
the number of protons, electrons and neutrons
only the number of protons and neutrons
only the number of protons and neutrons
only the valence electrons
only the valence electrons
The answer is: only the number of protons and neutrons. The atomic number gives the number of protons, and the atomic weight gives a rough estimate of the number of neutrons. However, the presence or absence of electrons cannot be determined solely from the atomic number and weight. Valence electrons, which determine an element's chemical properties, cannot be determined from this information alone.
What quality differentiates hydrogen (H) from the other elements in group 1, the alkali metals?
It has more than one valence electron.
It has more than one valence electron.
It is found by itself in nature.
It is found by itself in nature.
It is a non-metal.
It is a non-metal.
It is not very reactive.
The answer is: It is found by itself in nature. Hydrogen is unique among the elements in group 1, the alkali metals, because it is found as a diatomic molecule (H2) rather than as a single atom. Alkali metals like lithium, sodium, and potassium are typically found in nature as single atoms.
On which atomic property proposed by Henry Moseley is the current periodic table of the elements based?
atomic number
atomic number
atomic weight
atomic weight
nucleus size
nucleus size
electric charge
The answer is: atomic number. The current periodic table of the elements is based on the atomic number, which was proposed by Henry Moseley. The atomic number represents the number of protons in the nucleus of an atom and determines the element's identity. This property is used to arrange the elements in the periodic table in increasing order of atomic number.
You plan to pass alpha particles through a field that contains a consistent type of particle. Which configuration will result in the largest deflection of alpha particles?
low-energy alpha particles passing through a field of low mass-number-particles
low-energy alpha particles passing through a field of low mass-number-particles
low-energy alpha particles passing through a field of high mass-number-particles
low-energy alpha particles passing through a field of high mass-number-particles
high-energy alpha particles passing through a field of low mass-number-particles
high-energy alpha particles passing through a field of low mass-number-particles
high-energy alpha particles passing through a field of high mass-number-particles
high-energy alpha particles passing through a field of high mass-number-particles
The answer is: low-energy alpha particles passing through a field of high mass-number particles.
Alpha particles are helium nuclei consisting of two protons and two neutrons. When alpha particles pass through a field of particles, they experience Coulombic interactions with the other particles due to their positive charge. The larger the mass of the particles in the field, the greater the chance of a larger deflection or scattering of the alpha particles. Low-energy alpha particles have less kinetic energy and are more likely to interact and be deflected by the higher mass particles in the field.
Which statement about metals and nonmetals is correct?
Most metals are a solid under normal conditions, and most nonmetals are a liquid.
Most metals are a solid under normal conditions, and most nonmetals are a liquid.
Metals tend to be poor conductors of electricity, while nonmetals are strong conductors of electricity.
Metals tend to be poor conductors of electricity, while nonmetals are strong conductors of electricity.
Metals and nonmetals can both be found in any column of the periodic table.
Metals and nonmetals can both be found in any column of the periodic table.
Metals can be hammered into thin sheets, and nonmetals are brittle.
The correct statement is: Metals can be hammered into thin sheets, and nonmetals are brittle.
Metals are generally malleable and ductile, meaning they can be hammered into thin sheets and drawn into wires. On the other hand, nonmetals are typically brittle, meaning they are easily broken or shattered when subjected to stress. This is one of the key characteristics that differentiate metals from nonmetals.
Based on properties of elements in the periodic table, which element is the best conductor of thermal energy?
argon (Ar)
argon (Ar)
vanadium (V)
vanadium (V)
germanium (Ge)
germanium (Ge)
polonium (Po)
The answer is: vanadium (V). Among the given elements, vanadium is the best conductor of thermal energy. Vanadium is a transition metal and has high thermal conductivity compared to other elements in the periodic table. Argon, germanium, and polonium do not have as high thermal conductivity as vanadium.
Which element has four valence electrons?
potassium (K)
potassium (K)
beryllium (Be)
beryllium (Be)
silicon (Si)
silicon (Si)
sulfur (S)
The answer is: beryllium (Be). Beryllium has four valence electrons. Valence electrons are the electrons located in the outermost energy level of an atom and are involved in bonding with other atoms. Potassium has one valence electron, silicon has four valence electrons, and sulfur has six valence electrons.
Which statement best explains why hydrogen’s atomic number is equal to its mass?
Hydrogen only has one electron
Hydrogen only has one electron
Hydrogen is stable, with two electrons in its outer shell.
Hydrogen is stable, with two electrons in its outer shell.
Hydrogen is in the first row and the first column of the periodic table.
Hydrogen is in the first row and the first column of the periodic table.
Hydrogen does not have any neutrons.
The correct statement is: Hydrogen only has one electron.
The atomic number of an element represents the number of protons in the nucleus of an atom. Since hydrogen only has one proton in its nucleus, its atomic number is 1. The number of protons in an atom determines the element's identity. It is important to note that hydrogen can have different isotopes, which have different numbers of neutrons. However, the most common isotope of hydrogen, protium, does not have any neutrons.
Which statement correctly compares the valence electrons for atoms of francium (Fr) and barium (Ba)?
Barium has fewer valence electrons, but they are in a higher energy level.
Barium has fewer valence electrons, but they are in a higher energy level.
Francium has more valence electrons, and they are in a higher energy level.
Francium has more valence electrons, and they are in a higher energy level.
Barium has more valence electrons, and they are in a higher energy level.
Barium has more valence electrons, and they are in a higher energy level.
Francium has fewer valence electrons, but they are in a higher energy level.
The statement that correctly compares the valence electrons for atoms of francium (Fr) and barium (Ba) is: Barium has fewer valence electrons, but they are in a higher energy level.
In general, the atomic number determines the number of valence electrons, as valence electrons are located in the outermost energy level of an atom. Francium, with an atomic number of 87, has 7 valence electrons located in the seventh energy level. Barium, with an atomic number of 56, has 2 valence electrons located in the sixth energy level. Therefore, barium has fewer valence electrons, but those electrons are in a higher energy level compared to francium.
Why are the noble gases the least reactive elements?
They are the most electronegative elements.
They are the most electronegative elements.
They have an empty inner electron shell.
They have an empty inner electron shell.
They have a full valence electron shell.
They have a full valence electron shell.
They are the elements with the smallest atomic mass
The correct statement is: They have a full valence electron shell.
The noble gases (Group 18 elements) have a full valence electron shell, meaning their outermost energy level is completely filled with electrons. This full valence shell provides them with a high level of stability and makes them chemically inert. As a result, noble gases tend to not readily participate in chemical reactions and are therefore considered the least reactive elements.
Group 2 elements have two valence electrons. Which kind of bond will they most likely form, and why?
An ionic bond is likely because they will want to give away two valence electrons in order to become stable.
An ionic bond is likely because they will want to give away two valence electrons in order to become stable.
An ionic bond is likely because they are metals and will want to bond with nonmetals.
An ionic bond is likely because they are metals and will want to bond with nonmetals.
A metallic bond is likely because they are metals and can bond with other metals.
A metallic bond is likely because they are metals and can bond with other metals.
A covalent bond is likely because they want to share those two valence electrons in order to become stable.
The correct statement is: A covalent bond is likely because they want to share those two valence electrons in order to become stable.
Group 2 elements, also known as alkaline earth metals, have two valence electrons. In order to achieve a full valence electron shell, they can either gain or lose electrons. However, due to the relatively low ionization energies of these elements, it is more favorable for them to form covalent bonds by sharing their two valence electrons with nonmetallic elements. This allows both atoms to achieve a more stable electron configuration, fulfilling the octet rule and creating a stronger bond between them.
How many electrons can carbon accept from other atoms while bonding?
Two
Six
Eight
Four
Carbon can accept four electrons from other atoms while bonding.
Carbon has four valence electrons in its outermost energy level, and it needs a total of eight electrons to achieve a full valence electron shell. This allows it to form up to four covalent bonds by sharing its valence electrons with other atoms. By sharing these electrons, carbon can achieve a stable electron configuration, known as an octet, and form various stable compounds.
An element has six valence electrons. Which ionic charge will its ion carry?
6–
6–
6+
6+
2+
2+
2–
An element with six valence electrons would most likely carry a charge of 2-.
The number of valence electrons influences how an element gains or loses electrons to achieve a stable electron configuration. Elements tend to gain or lose electrons to either empty or fill their valence electron shell. Since this element has six valence electrons, it only needs to gain two additional electrons to achieve a full valence shell of eight electrons. Therefore, it would form an ion with a charge of 2-.