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The element molybdenum is characterized by the chemical symbol Mo and possesses an atomic number of 42.
Answer: True
The element molybdenum is indeed identified by the chemical symbol Mo and has an atomic number of 42, indicating 42 protons in its nucleus.
The nomenclature 'molybdenum' is derived from the Ancient Greek term 'molybdos,' which signifies 'lead,' reflecting historical confusion with lead ores.
Answer: True
The name 'molybdenum' originates from the Ancient Greek word 'molybdos,' meaning 'lead,' a designation arising from the historical confusion of molybdenum ores with lead ores.
Carl Wilhelm Scheele discovered molybdenum in 1778, and Peter Jacob Hjelm was the first to isolate the pure metal in 1781.
Answer: True
Historical records confirm that Carl Wilhelm Scheele identified molybdenum as a distinct element in 1778, and Peter Jacob Hjelm subsequently succeeded in isolating the pure metal in 1781.
The standard atomic weight of molybdenum is approximately 95.95 grams per mole.
Answer: True
The standard atomic weight assigned to molybdenum is 95.95 grams per mole, with a measurement uncertainty of ±0.01.
There are 39 known isotopes of molybdenum, with seven of these occurring naturally.
Answer: True
The element molybdenum comprises 39 known isotopes, ranging in atomic mass from 81 to 119. Of these, seven are found in natural abundance.
Molybdenum-98 is the most abundant naturally occurring isotope of molybdenum, constituting approximately 24.14% of the element's natural abundance.
Answer: True
Molybdenum-98 holds the distinction of being the most abundant naturally occurring isotope, representing approximately 24.14% of molybdenum's total natural isotopic composition.
Molybdenum-100 is the only naturally occurring isotope that is unstable; it undergoes double beta decay into Ruthenium-100 over an extremely long half-life.
Answer: True
Molybdenum-100 is unique among the naturally occurring isotopes as it is unstable, undergoing double beta decay to transform into Ruthenium-100 with an estimated half-life of 7.07 x 10^18 years.
Historically, molybdenum ores, particularly molybdenite, were often mistaken for graphite or lead ores due to their appearance.
Answer: True
In historical contexts, molybdenum-containing minerals like molybdenite were frequently misidentified as graphite or lead ores owing to similarities in their physical characteristics.
The name 'molybdenum' originates from the Ancient Greek word 'molybdos,' meaning 'lead,' reflecting historical confusion with lead ores.
Answer: True
The etymology of 'molybdenum' traces back to the Ancient Greek term 'molybdos,' signifying 'lead,' due to the historical misidentification of molybdenum ores with lead ores.
Molybdenum is the 54th most abundant element in the Earth's crust, indicating moderate abundance, not scarcity.
Answer: True
With an average concentration of 1.5 parts per million, molybdenum ranks as the 54th most abundant element in the Earth's crust, signifying a moderate level of prevalence.
What is the chemical symbol and atomic number assigned to molybdenum?
Answer: Symbol: Mo, Atomic Number: 42
The element molybdenum is designated by the chemical symbol Mo and possesses an atomic number of 42.
From which ancient language and word does the name "molybdenum" originate, and what did it mean?
Answer: Ancient Greek, 'molybdos', meaning 'lead'
The name 'molybdenum' is derived from the Ancient Greek word 'molybdos,' which translates to 'lead,' reflecting historical confusion with lead ores.
Who is credited with discovering molybdenum as a distinct element, and who first isolated the pure metal?
Answer: Discovery: Carl Wilhelm Scheele (1778); Isolation: Peter Jacob Hjelm (1781)
Carl Wilhelm Scheele is credited with discovering molybdenum in 1778, and Peter Jacob Hjelm successfully isolated the pure metal in 1781.
What is the standard atomic weight of molybdenum?
Answer: Approximately 95.95 grams per mole
The standard atomic weight of molybdenum is established at approximately 95.95 grams per mole.
How many known isotopes of molybdenum exist, and how many of them are naturally occurring?
Answer: 39 known isotopes, 7 naturally occurring
There are 39 known isotopes of molybdenum, of which seven are found naturally occurring on Earth.
Which naturally occurring isotope of molybdenum is the most abundant?
Answer: Molybdenum-98
Molybdenum-98 is the most abundant among the naturally occurring isotopes of molybdenum.
What happens to the naturally occurring isotope Molybdenum-100?
Answer: It is unstable and undergoes double beta decay into Ruthenium-100.
Molybdenum-100 is the sole naturally occurring isotope that is unstable; it decays via double beta decay into Ruthenium-100 over an exceptionally long period.
Pure molybdenum presents as a silvery-grey metal and is notably resistant to tarnishing at ambient temperatures.
Answer: True
Pure molybdenum is characterized by its silvery-grey appearance and exhibits resistance to tarnishing under normal room temperature conditions.
Molybdenum exhibits one of the highest melting points among naturally occurring elements, ranking sixth globally in this regard.
Answer: True
Molybdenum possesses the sixth-highest melting point among all naturally occurring elements, a property that contributes significantly to its utility in high-temperature applications.
Most molybdenum compounds exhibit limited solubility in water, although they can form soluble salts like molybdates.
Answer: True
The majority of molybdenum compounds are not highly soluble in water; however, they can form the molybdate ion (MoO4^2-), which subsequently forms more soluble salts.
Molybdenum has a Mohs hardness of 5.5, which is softer than quartz (Mohs hardness of 7).
Answer: False
Molybdenum possesses a Mohs hardness of 5.5, rendering it softer than quartz, which has a Mohs hardness of 7.
At room temperature, molybdenum is relatively inert and does not visibly react with oxygen or water.
Answer: True
Under ambient conditions, molybdenum demonstrates considerable inertness, showing no visible reaction with either oxygen or water.
Molybdenum begins to oxidize weakly at temperatures above 300 °C, with more significant oxidation occurring above 600 °C.
Answer: True
Molybdenum's oxidation process commences weakly at temperatures exceeding 300 °C, intensifying significantly at temperatures above 600 °C, leading to the formation of molybdenum trioxide.
Gaseous molybdenum exists as diatomic molecules (Mo2) that feature a sextuple bond, signifying a high order of covalent bonding.
Answer: True
In the gaseous state, molybdenum forms diatomic molecules (Mo2) characterized by a sextuple bond, representing an unusually high number of covalent bonds between the two metal atoms.
Molybdenum commonly exhibits oxidation states of +4 and +6, although it can form compounds in a range of other oxidation states.
Answer: True
The most frequently observed oxidation states for molybdenum are +4 and +6. However, it is capable of forming compounds across a broader spectrum, including negative and intermediate positive states.
Molybdenum and tungsten exhibit significant chemical similarities, rather than very different properties, owing to their placement within the same group (Group 6) of the periodic table.
Answer: True
Due to their location in Group 6 of the periodic table, molybdenum and tungsten share numerous chemical similarities, influencing their reactivity and compound formation.
Molybdenum's low coefficient of thermal expansion contributes to its stability and utility in high-temperature applications.
Answer: True
The low coefficient of thermal expansion of molybdenum means it undergoes minimal dimensional change with temperature fluctuations, enhancing its stability and suitability for high-temperature environments.
Molybdenum's exceptionally high melting point (2,623 °C) makes it highly suitable, not unsuitable, for high-temperature applications.
Answer: True
The elevated melting point of molybdenum renders it exceptionally resistant to thermal deformation, making it highly advantageous for applications requiring stability at extreme temperatures.
Which description best fits the physical appearance of pure molybdenum?
Answer: A silvery-grey metal known for its hardness and resistance to tarnishing.
Pure molybdenum is characterized as a silvery-grey metal possessing considerable hardness and resistance to tarnishing under ambient conditions.
What is notable about molybdenum's melting point compared to other naturally occurring elements?
Answer: It ranks sixth highest among all naturally occurring elements.
Molybdenum possesses one of the highest melting points among naturally occurring elements, ranking sixth in this regard, which is crucial for its high-temperature applications.
Which statement accurately describes the solubility of most molybdenum compounds?
Answer: Most are not very soluble in water, though they can form soluble salts like molybdates.
The majority of molybdenum compounds exhibit limited solubility in water; however, they can form the molybdate ion, which subsequently yields more soluble salts.
What is the Mohs hardness of molybdenum?
Answer: 5.5
Molybdenum exhibits a Mohs hardness rating of 5.5.
How does molybdenum behave when exposed to oxygen and water at room temperature?
Answer: It is relatively inert and shows no visible reaction.
At room temperature, molybdenum demonstrates significant inertness and does not undergo visible reactions with oxygen or water.
At what temperature does molybdenum begin to oxidize weakly in the presence of oxygen?
Answer: Above 300 °C
Molybdenum initiates weak oxidation in the presence of oxygen at temperatures exceeding 300 °C, with more substantial oxidation occurring above 600 °C.
What is chemically unique about diatomic molecules of molybdenum in the gaseous state?
Answer: They exhibit a sextuple bond.
Diatomic molecules of molybdenum (Mo2) in the gaseous phase are notable for featuring a sextuple bond, indicating a high degree of covalent interaction between the two atoms.
Which oxidation states are most commonly observed for molybdenum?
Answer: +4 and +6
The oxidation states most frequently exhibited by molybdenum are +4 and +6, although it can also form compounds in other oxidation states.
What chemical similarity exists between molybdenum and tungsten?
Answer: They share many chemical similarities due to their periodic table placement.
Molybdenum and tungsten display considerable chemical similarities, largely attributable to their shared position within Group 6 of the periodic table.
Molybdenum does not occur naturally as a free metal on Earth; it is typically found in its mineral ores.
Answer: True
Molybdenum is not found in its pure metallic form in nature. Instead, it is commercially extracted from various mineral ores, predominantly molybdenite (MoS2).
Contrary to the assertion that approximately 80% of molybdenum's global production is used in the semiconductor industry, the primary industrial application, consuming this proportion, is in the production of steel alloys.
Answer: False
Approximately 80% of molybdenum's global production is utilized in metallurgy, specifically for enhancing steel alloys, rather than in the semiconductor industry.
The two most commercially significant compounds of molybdenum are molybdenum disulfide (MoS2) and molybdenum trioxide (MoO3).
Answer: True
Molybdenum disulfide (MoS2), the primary mineral source, and molybdenum trioxide (MoO3), a key precursor, are recognized as the two most commercially important compounds of molybdenum.
The conversion of molybdenum disulfide (MoS2) to molybdenum trioxide (MoO3) is achieved by roasting MoS2 in the presence of air at elevated temperatures (approximately 700 °C), not in the absence of air.
Answer: True
Molybdenum disulfide (MoS2) is converted to molybdenum trioxide (MoO3) through a process of roasting in air at approximately 700 °C, yielding sulfur dioxide as a byproduct.
Metallic molybdenum is typically produced by reducing molybdenum trioxide (MoO3) with hydrogen gas at high temperatures.
Answer: True
The primary method for producing metallic molybdenum involves the reduction of molybdenum trioxide (MoO3) using hydrogen gas at elevated temperatures. Ferromolybdenum for alloys is often produced via an aluminothermic reaction.
TZM is a molybdenum-based superalloy containing titanium and zirconium, valued for its superior strength and corrosion resistance at high temperatures.
Answer: True
TZM (Titanium-Zirconium-Molybdenum) is a molybdenum-based superalloy renowned for its enhanced strength and resistance to corrosion at elevated temperatures, making it suitable for demanding applications.
While molybdenum compounds serve as catalysts, molybdenum disulfide (MoS2) is primarily recognized for its application as a solid lubricant and anti-wear additive.
Answer: True
Molybdenum disulfide (MoS2) is predominantly utilized as a high-performance solid lubricant and anti-wear additive, particularly effective under conditions of high pressure and temperature.
Molybdenum targets are employed in mammography X-ray tubes because they efficiently generate X-rays within a specific energy range (17-20 keV), which is optimal for imaging the soft tissues of the breast.
Answer: True
The use of molybdenum targets in mammography is due to their ability to produce X-rays in the 17-20 keV range, an energy spectrum ideal for visualizing the soft tissues of the breast with high contrast.
During World War I, molybdenum served as a substitute for tungsten in steel alloys for military equipment.
Answer: True
In World War I, molybdenum was strategically employed as a substitute for tungsten in steel alloys, enhancing the performance of armor plating and artillery components.
The principal ore from which molybdenum is commercially extracted is molybdenite (MoS2).
Answer: True
Molybdenite (MoS2) is the primary mineral source utilized for the commercial extraction of molybdenum, often found in association with copper deposits.
Molybdenum serves as a catalyst in analyzers used for monitoring atmospheric pollutants like nitrogen oxides (NOx) in power plants.
Answer: True
Molybdenum acts as a catalyst in certain pollution control monitoring systems, aiding in the detection and analysis of nitrogen oxides (NOx) by facilitating their conversion to nitric oxide (NO).
Commercial molybdenum extraction typically involves roasting molybdenite (MoS2) in air to form molybdenum trioxide (MoO3), which is subsequently dissolved in ammonia to produce ammonium molybdate for further processing.
Answer: True
The standard commercial process for molybdenum extraction begins with roasting molybdenite (MoS2) to yield molybdenum trioxide (MoO3), followed by dissolution in ammonia to form ammonium molybdate, a precursor for refining.
In TZM (Titanium-Zirconium-Molybdenum) alloys, molybdenum is the primary component responsible for providing excellent strength and creep resistance at elevated temperatures.
Answer: True
Molybdenum forms the base of TZM alloys, imparting superior high-temperature strength and creep resistance, which are critical properties for applications like rocket nozzles and nuclear reactor components.
Molybdenum anodes in mammography X-ray tubes produce X-rays at an energy level optimal for imaging soft breast tissue, not dense bone structures.
Answer: True
The specific energy spectrum generated by molybdenum anodes is tailored for optimal imaging of soft breast tissue, enhancing contrast and detail for diagnostic purposes.
Molybdenum-based catalysts are extensively used in hydrodesulfurization (HDS) processes to remove sulfur from crude oil.
Answer: True
Molybdenum, often combined with cobalt or nickel, serves as a crucial catalyst in hydrodesulfurization (HDS), a process vital for removing sulfur compounds from petroleum feedstocks.
The addition of molybdenum to steel significantly increases its resistance to softening at high temperatures, thereby enhancing its suitability for high-speed cutting tools.
Answer: True
Incorporating molybdenum into steel alloys enhances hardness, strength, and wear resistance, particularly at elevated temperatures, making them ideal for high-speed machining applications.
How does molybdenum typically occur in nature on Earth?
Answer: Primarily in mineral ores, often in oxidized forms.
Molybdenum is not found in its native metallic state; it predominantly occurs in nature within mineral ores, frequently in oxidized chemical states.
What is the predominant industrial application of molybdenum, consuming the majority of its global production?
Answer: In the production of high-strength steel alloys.
The primary industrial utilization of molybdenum, accounting for approximately 80% of its global production, is in the manufacturing of steel alloys to enhance properties like strength and hardness.
Identify the two most commercially important compounds of molybdenum mentioned in the source.
Answer: Molybdenum trioxide and molybdenum disulfide
Molybdenum disulfide (MoS2) and molybdenum trioxide (MoO3) are identified as the two compounds of molybdenum with the greatest commercial significance.
How is molybdenum disulfide (MoS2) typically converted into molybdenum trioxide (MoO3)?
Answer: By roasting MoS2 in air at approximately 700 °C.
Molybdenum disulfide (MoS2) is typically converted into molybdenum trioxide (MoO3) through a process of roasting in air at temperatures around 700 °C.
What is the primary method described for producing metallic molybdenum?
Answer: Reduction of molybdenum trioxide (MoO3) with hydrogen gas at high temperatures.
Metallic molybdenum is predominantly produced via the high-temperature reduction of molybdenum trioxide (MoO3) using hydrogen gas.
What is TZM alloy, and why is it significant?
Answer: A titanium-zirconium-molybdenum superalloy valued for high-temperature strength.
TZM is a significant molybdenum-based superalloy, incorporating titanium and zirconium, which provides exceptional strength and creep resistance at elevated temperatures.
What is a primary application of molybdenum disulfide (MoS2)?
Answer: As a solid lubricant and anti-wear additive.
Molybdenum disulfide (MoS2) is primarily recognized and utilized for its effectiveness as a solid lubricant and an anti-wear additive in various mechanical applications.
Why are molybdenum targets specifically used in mammography X-ray tubes?
Answer: They efficiently generate X-rays in an energy range optimal for soft breast tissue imaging.
Molybdenum targets are selected for mammography X-ray tubes due to their capacity to produce X-rays at an energy level optimized for imaging the soft tissues of the breast, thereby enhancing diagnostic clarity.
What historical role did molybdenum play during World War I?
Answer: It served as a substitute for tungsten in steel alloys for military equipment.
During World War I, molybdenum was utilized as a critical substitute for tungsten in steel alloys, enhancing the durability and performance of military hardware such as armor plating and artillery components.
What is the primary mineral source for commercial molybdenum extraction?
Answer: Molybdenite (MoS2)
Molybdenite (MoS2) is the principal mineral ore from which molybdenum is commercially extracted.
What is the role of molybdenum in the context of hydrodesulfurization (HDS) in petroleum refining?
Answer: It is a catalyst, often with cobalt, used to remove sulfur compounds from crude oil.
Molybdenum, frequently combined with cobalt, functions as a key catalyst in hydrodesulfurization (HDS) processes, essential for eliminating sulfur compounds from crude oil.
Molybdenum is a critical component of nitrogenase enzymes, playing a crucial role in the biological process of nitrogen fixation.
Answer: True
Molybdenum is an essential cofactor for nitrogenase enzymes, which are fundamental to biological nitrogen fixation, the process converting atmospheric nitrogen into ammonia usable by organisms.
Molybdenum-99 is not directly utilized in medical diagnostic imaging; rather, it serves as the parent radioisotope for Technetium-99m, which is the isotope commonly employed for such diagnostic purposes.
Answer: True
Molybdenum-99, a fission product, is significant not for direct use in imaging, but as the parent isotope for Technetium-99m, the most widely used radioisotope in medical diagnostic imaging.
Molybdenum is an essential trace element for humans, acting as a cofactor for enzymes involved in metabolism and detoxification.
Answer: True
As an essential trace element, molybdenum functions as a cofactor for several key human enzymes, facilitating crucial metabolic pathways and detoxification processes.
Organ meats like liver are considered primary dietary sources of molybdenum.
Answer: True
Organ meats, such as liver, are identified as significant dietary sources of molybdenum, containing approximately 1.5 parts per million.
Excessive chronic intake of molybdenum can lead to adverse health effects, including diarrhea and stunted growth.
Answer: True
While essential in trace amounts, excessive and prolonged consumption of molybdenum can result in adverse health consequences, such as gastrointestinal distress, impaired growth, and potential organ damage.
High molybdenum intake can potentially lead to copper deficiency by interfering with copper metabolism and increasing its excretion.
Answer: True
Elevated dietary molybdenum levels can disrupt copper metabolism, potentially leading to copper deficiency by inhibiting copper's binding to plasma proteins and augmenting its urinary excretion.
The Recommended Dietary Allowance (RDA) for molybdenum for adults aged 19 and older in the United States is 45 micrograms per day.
Answer: True
The established Recommended Dietary Allowance (RDA) for molybdenum for adult individuals (19 years and older) in the United States is 45 micrograms per day.
The US National Academy of Medicine has established a tolerable upper intake level (UL) for molybdenum at 2000 micrograms per day for adults.
Answer: True
The US National Academy of Medicine has set the tolerable upper intake level (UL) for molybdenum for adults at 2000 micrograms per day, defining a threshold generally considered safe for consumption.
The European Food Safety Authority (EFSA) recommends a lower tolerable upper intake level (UL) for molybdenum (600 micrograms per day) compared to the US recommendation (2000 micrograms per day).
Answer: True
The European Food Safety Authority (EFSA) advises a tolerable upper intake level (UL) of 600 micrograms per day for adults, which is lower than the US recommendation of 2000 micrograms per day.
Exposure to molybdenum dust and fumes can cause irritation and potential systemic toxicity.
Answer: True
Inhalation or ingestion of molybdenum dust and fumes, often encountered in industrial settings, may lead to respiratory irritation and potential systemic toxic effects.
Molybdenum is a critical component of the iron-molybdenum cofactor (FeMoco), which is essential for the process of nitrogen fixation.
Answer: True
The iron-molybdenum cofactor (FeMoco), containing molybdenum, is the active site in nitrogenase enzymes responsible for catalyzing nitrogen fixation.
Molybdopterin is an organic molecule that binds to molybdenum to form the molybdenum cofactor (Moco), which is essential for enzyme function; it is not a metal itself.
Answer: True
Molybdopterin is an organic pterin derivative that coordinates with molybdenum to form the molybdenum cofactor (Moco), crucial for the activity of many molybdenum-dependent enzymes.
Congenital molybdenum cofactor deficiency results in impaired sulfite metabolism and severe neurological damage due to the inability to synthesize the molybdenum cofactor.
Answer: True
This rare inherited disorder prevents the synthesis of the molybdenum cofactor, leading to critical impairments in sulfite metabolism and significant neurological deficits.
High molybdenum levels in grazing land can induce copper deficiency in livestock, not copper toxicity. This condition, known as 'teartness,' can lead to various health issues.
Answer: True
Excessive molybdenum in forage can interfere with copper absorption and utilization in livestock, causing copper deficiency (teartness) rather than copper toxicity.
Studies suggest molybdenum may contribute to preventing tooth decay by enhancing enamel's resistance to acid erosion.
Answer: True
Research indicates that molybdenum, found in human tooth enamel, may play a role in preventing dental caries by potentially increasing the enamel's resistance to demineralization.
A correlation has been observed between dietary molybdenum deficiency and an increased risk of certain cancers, notably esophageal cancer in specific geographic regions with low soil molybdenum levels.
Answer: True
In regions characterized by low soil molybdenum content, dietary deficiency of this element has been linked to a higher incidence of certain cancers, particularly esophageal cancer.
Molybdenum is essential for the function of several key enzymes, including sulfite oxidase and xanthine oxidase, playing vital roles in metabolic pathways.
Answer: True
Molybdenum serves as an indispensable cofactor for critical enzymes such as sulfite oxidase and xanthine oxidase, which are central to various metabolic processes and detoxification mechanisms.
The FeMoco (iron-molybdenum cofactor) in nitrogenase enzymes is characterized by the presence of both iron and molybdenum, which are essential for its catalytic activity in nitrogen fixation.
Answer: True
The FeMoco cofactor, vital for nitrogenase function, contains both iron and molybdenum atoms, which are indispensable for catalyzing the conversion of atmospheric nitrogen into ammonia.
Molybdenum is primarily excreted from the human body via the urine, typically in the form of molybdate ions.
Answer: True
The primary route for molybdenum excretion from the human body is through the urine, predominantly as molybdate ions, with the excretion rate generally correlating with dietary intake.
Tungsten can inhibit molybdenum absorption and utilization in biological systems, acting as a competitive antagonist.
Answer: True
Tungsten can interfere with molybdenum's biological functions by competitively inhibiting its absorption and utilization, thereby acting as an antagonist.
Ammonium tetrathiomolybdate is used therapeutically due to its ability to chelate copper, finding application in treating copper toxicosis and Wilson's disease.
Answer: True
Ammonium tetrathiomolybdate possesses therapeutic utility as a copper-chelating agent, employed in the management of copper toxicosis and Wilson's disease, and is being investigated for anti-angiogenic properties.
In bacteria, molybdenum is crucial for enzymes involved in nitrogen fixation, not primarily energy production.
Answer: True
Molybdenum plays a vital role in bacterial metabolism, primarily through its involvement in nitrogenase enzymes essential for nitrogen fixation, rather than energy production pathways.
A correlation has been observed between dietary molybdenum deficiency and an increased risk of certain cancers, notably esophageal cancer in specific geographic regions with low soil molybdenum levels.
Answer: True
Epidemiological studies suggest a link between low dietary intake of molybdenum, often associated with low soil concentrations, and an elevated risk of developing certain cancers, such as esophageal cancer.
Molybdenum is a key component of xanthine oxidase, which catalyzes the oxidation of xanthine to uric acid. This statement incorrectly reverses the reaction direction.
Answer: False
Molybdenum is essential for xanthine oxidase, but the enzyme catalyzes the oxidation of xanthine to uric acid, not the reverse reaction.
The US sets a higher tolerable upper intake level (UL) for molybdenum (2000 µg/day) than the EU (600 µg/day).
Answer: True
Regulatory bodies in the US establish a higher tolerable upper intake level (UL) for molybdenum compared to the European Union's recommendation.
What vital biological process involves molybdenum as a critical component of nitrogenase enzymes?
Answer: Nitrogen fixation
Molybdenum is an essential component of nitrogenase enzymes, which are critical for the biological process of nitrogen fixation, converting atmospheric nitrogen into ammonia.
Molybdenum-99 is significant because it is the parent radioisotope for which medically important isotope?
Answer: Technetium-99m
Molybdenum-99 serves as the parent radioisotope for Technetium-99m, a critical isotope widely employed in nuclear medicine for diagnostic imaging procedures.
What is the essential role of molybdenum in human metabolism?
Answer: It acts as a cofactor for enzymes involved in metabolism and detoxification.
Molybdenum functions as an essential cofactor for several key enzymes in the human body, playing a critical role in metabolic processes and the detoxification of harmful substances.
Which of the following is listed as a primary dietary source of molybdenum?
Answer: Organ meats like liver
Organ meats, such as liver, are identified as significant dietary sources of molybdenum, alongside other foods like green beans and grains.
What potential adverse health effects can result from excessive chronic intake of molybdenum?
Answer: Diarrhea, stunted growth, and potential organ damage.
Excessive chronic consumption of molybdenum may lead to adverse health outcomes including diarrhea, impaired growth, reduced fertility, and potential damage to organs such as the lungs, kidneys, and liver.
How can high dietary molybdenum levels negatively impact copper levels in the body?
Answer: By interfering with copper metabolism and increasing its excretion.
Elevated molybdenum intake can disrupt copper metabolism, leading to copper deficiency by hindering copper's binding to plasma proteins and increasing its urinary excretion.
Compare the US and EU tolerable upper intake levels (UL) for molybdenum for adults.
Answer: US UL is 2000 µg/day; EU UL is 600 µg/day.
The US National Academy of Medicine sets the tolerable upper intake level (UL) for molybdenum at 2000 µg/day for adults, whereas the European Food Safety Authority (EFSA) recommends a lower UL of 600 µg/day.
In bacteria, the FeMoco cofactor, containing molybdenum, is essential for which process?
Answer: Nitrogen fixation
The FeMoco cofactor, which includes molybdenum, is indispensable for nitrogen fixation in bacteria, enabling the conversion of atmospheric nitrogen into ammonia.
What is the relationship between low soil molybdenum and health risks in certain populations?
Answer: Linked to a higher incidence of certain cancers, like esophageal cancer.
Low molybdenum levels in soil, leading to dietary deficiency, have been associated with an increased risk of developing certain cancers, notably esophageal cancer in specific geographical areas.
What is the function of molybdenum in the enzyme xanthine oxidase?
Answer: It catalyzes the oxidation of xanthine to uric acid.
Molybdenum is a crucial component of xanthine oxidase, an enzyme responsible for catalyzing the oxidation of xanthine to uric acid in humans.