By beta, tungsten 188 decays. The mechanism through which an insecure atomic structure is produced is known as radioactive decay.
How does radioactive decay work?The process through which highly unstable molecular nucleus loses its energy through radiation is described as radioactive decay, also characterized as nuclear decay, radiography, radioactivity breakdown, or nuclear disintegration. A substance that has unstable nuclei is regarded as radioactive. For a large variety of human activities, radioactive decay is crucial.
What occurs when radioactive material decays?Alpha, beta, and/or gamma rays are all types of ionizing radiation that are released when radioactive atoms decay. Because the energy is powerful enough to dislodge firmly coupled electrons from just an atom's orbit, it is known as ionizing radiation. As a result, the atom develops into a charged ion.
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Base your answer on the choices below. (A) Pauli exclusion principle (B) Heisenberg uncertainty principle (C) Hund's rule (D) Wave nature of matter Which is responsible for interference patterns being exhibited by electrons
Wave nature of matter is responsible for interference pattern being exhibited by electrons.
Shortly after de Broglie proposed the wave nature of matter, two scientists at Bell Labs, C.J. showed experimentally that electrons can exhibit wave-like behavior. The wave-like motion of electrons is mathematically described by the so-called Bloch wave function. Named after his 20th-century physicist Felix Bloch, who first described the behavior of electrons in crystalline solids, these wavefunctions are complex. That is, it has both real and imaginary components.
These waves are called matter waves because electrons are a type of matter. Here,we relate the quantitative features of matter waves to familiar and measurable physical quantities such as energy, mass, and momentum.
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How does Angelica Hernandez work help others
Answer:Angelica currently works on energy efficiency programs for Nexant, Inc, an Arizona-based company focused on clean energy solutions.
Explanation:
Identify the 13 c nmr chemical shift for each carbon atom in a molecule of 1-penten-3-one
Carbon 1: δ = 2.09 ppm (The C1 atom is a methyl group, and is in a tertiary environment, which typically corresponds to a chemical shift of around 2.09 ppm).
What is chemical shift?Chemical shift is a term used in NMR spectroscopy to describe the relative difference in the resonance frequency of a nucleus in a molecule compared to a reference frequency.
2. Carbon 2: δ = 11.81 ppm (This is the carbonyl carbon, and is in a sp2 hybridized environment, which typically corresponds to a chemical shift of around 11.81 ppm).
3. Carbon 3: δ = 13.92 ppm (This is the terminal carbon of the pentene chain, and is in a sp3 hybridized environment, which typically corresponds to a chemical shift of around 13.92 ppm).
4. Carbon 4: δ = 16.53 ppm (The C4 atom is a methylene group, and is in a secondary environment, which typically corresponds to a chemical shift of around 16.53 ppm).
5. Carbon 5: δ = 17.86 ppm (The C5 atom is a quaternary carbon, and is in a sp3 hybridized environment, which typically corresponds to a chemical shift of around 17.86 ppm).
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10. What would the new concentration be, in percentage, of 1.5 ml of a 10% solution that has been increased with normal saline to 3.0 ml
The 1.5 ml of a 10% solution that was made into a 3.0 ml solution by adding normal saline now has a new concentration of 5%.
The amount of material in a certain area is referred to as concentration in chemistry. Another definition states that concentration is the ratio of a solution's solute to its entire solution or solvent. Mass per unit volume is a common way to express concentration. However, moles or units of volume can also be used to express the solute concentration. Concentration could be per unit mass instead of volume. Concentration can be computed for any mixture, despite often being used with chemical solutions.
By mathematically dividing the mass, moles, or volume of the solute by the mass, moles, or volume of the solution, one may calculate the concentration (or, less commonly, the solvent).
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A force of 180 N to the right and a force of 180 N to the left.
Answer:
180 N + 180 N = 360N
Explanation:
since they are all force of different side, you will add them.
Which of the following ions has the largest radius?
a. Na+
b. K+
c. CS+
d. Li+
The size of an ion is determined by its atomic radius, which is a measure of the size of the atom from which the ion is formed. The atomic radius of an atom is generally determined by the size of its electron cloud. The size of the electron cloud is influenced by the number of electrons and the energy levels they occupy.
Of the ions given, Li+ has the smallest atomic radius because it has the smallest number of electrons and the highest effective nuclear charge, which means that its electrons are held more closely to the nucleus. Na+, K+, and CS+ have larger atomic radii than Li+ because they have more electrons and lower effective nuclear charges, which means that their electrons are held more weakly by the nucleus.
Therefore, the answer is CS+ has the largest radius.
Chlorine has an average atomic mass of 35.45 amu. The two natrually occuring isotopes of chlorine are chlorine-35 and chlorine-37. why does this indicate that most chlorine atoms contain 18 nuetrons?
Most chlorine atoms contain 18 neutrons as mole ratio of chlorine-35 and chlorine-37 is more than 1.
What is an atom?An atom is defined as the smallest unit of matter which forms an element. Every form of matter whether solid,liquid , gas consists of atoms . Each atom has a nucleus which is composed of protons and neutrons and shells in which the electrons revolve.
The protons are positively charged and neutrons are neutral and hence the nucleus is positively charged. The electrons which revolve around the nucleus are negatively charged and hence the atom as a whole is neutral and stable due to presence of oppositely charged particles.
let the moles of chlorine-35 is n1 and chlorine-37 is n2
now we will use the formula of average atomic mass
M=n₁M₁+n₂M₂/n₁+n₂
let say, n₁/n₂=x
substitution gives,35.45=x(35)+37/x+1 which on solving gives x=3.44
since mole ratio is more than 1, that's why most chlorine atoms have 18 neutrons.
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how could you use this pattern to predict how the element may behave in a chemical reaction
Answer:
it can predict the properties of new elements, because it organizes the elements according to their atomic numbers.
Creating new elements is not a simple process. Scientists use a particle accelerator to smash light atoms into a thin metallic foil that contains heavier atoms. They hope that the two nuclei at the centre of these atoms will fuse and form a heavier nucleus.
When these heavy elements form, they are usually highly unstable. They decay so quickly that we don’t usually see the element itself. Instead, we see a decay product. In that respect, even new elements aren't always 'discovered' directly. In some cases, scientists haven’t synthesized enough of the element for us to know what the element even looks like! Nevertheless, we consider the elements as known. We name them and list them the periodic table.
For example, in 2003, scientists first observed element 115 (ununpentium, Uup) They bombarded americium-243 with calcium-248 ions and produced four atoms of Uup, which lived for less than one fifth of a second.
₂₀ ⁴⁸Ca + ₉₅²⁴³Am → ₁₁₅²⁸⁸Uup + 3 ₀¹n
It took until September 2013 for the discovery to be confirmed, and about 50 atoms have been synthesized to date.
We can predict the properties of Uup because the Periodic Table organizes elements according to their atomic number.
What is a neutral atom and has 14 protons?
A neutral atom and has 14 protons is Silicon
Each of the elements in the Periodic Table has an individual atomic number, or a specific number of protons in its nucleus.
The total number of protons that make up an atom's nucleus is represented by the atomic number of that atom, as is well known. We know that an atom has proton of 14, so the atomic number of that neutral atom is 14. we can check on the periodic table an atom that have 14 atomic number is silicon.
Therefore, the neutral atom and has 14 protons is Silicon
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Hydrochloric acid (HCl) is combined with cesium hydroxide (CsOH) in a neutralization reaction. Which ions will combine to form a salt
The ions will combine to form a salt are Cl- and Cs+ when Hydrochloric acid (HCl) is combined with cesium hydroxide (CsOH) in a neutralization reaction.
HCl + CsOH --> CsCl + H2O
Cesium chloride is the salt that results from the neutralization of hydrochloric acid with cesium hydroxide. Because both of the bonds in salt compounds the positively charged cesium ion and the negatively charged chloride ion have electrical charges, they are referred to as ionic bonds. A neutralization reaction occurs when an acid and a base combine to form salt and water in an aqueous solution. A salt is the name for the aqueous cesium chloride that is created during the process.
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How do you calculate number of molecules?
Determine the substance's molecular weight in units of one mole, then divide the molar mass value by the molecular mass, and multiply the result by the Avogadro constant to get the required number of molecules.
It is possible to determine the number of molecules by using the relationship between the number of moles and Avogadro's number, which is provided by;
1 mole = Avogadro's constant (NA)
The number of molecules will equal the product of the number of moles and Avogadro's number, which is determined after the number of moles has been determined
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Determine the equilibrium constant Kc and the reaction quotient Qc for a reversible reaction.
Answer:
Explanation:
The equilibrium constant (Kc) is a measure of the relative concentrations of the reactants and products at equilibrium for a given chemical reaction. It is defined as the ratio of the product concentrations raised to their stoichiometric coefficients, to the reactant concentrations raised to their stoichiometric coefficients. For a general reversible reaction
aA + bB <=> cC + dD
The equilibrium constant is defined as:
Kc = [C]^c [D]^d / [A]^a [B]^b
where [X] represents the concentration of species X (in molarity units), and the superscripts on the concentrations represent the stoichiometric coefficients of the species in the balanced equation for the reaction.
The reaction quotient (Qc) is similar to the equilibrium constant, but it is calculated using the concentrations of the reactants and products at a given point in time, rather than at equilibrium. The reaction quotient is also defined as the ratio of the product concentrations raised to their stoichiometric coefficients, to the reactant concentrations raised to their stoichiometric coefficients, and is calculated using the same equation as Kc, but with the concentrations at a specific point in time, rather than at equilibrium.
Qc = [C]^c [D]^d / [A]^a [B]^b
It can be used to predict the direction of reaction depending on the sign of Qc, Kc.
If Qc < Kc, the reaction will shift in the direction of products.
If Qc > Kc, the reaction will shift in the direction of reactants
If Qc = Kc, the reaction is at equilibrium.
If you want to know more about equilibrium reaction you can check on Le Chatelier's principle.
A sample of a gas has a mass of 14.2g and occupies a volume of 0.678 liters at 25 C and a pressure of 0.80 atm. what is the density of a gas under these conditions
The density of gas can change, in contrast to the density of solids or liquids. This is due to the fact that gas is not compact and that temperature and pressure have an impact on its molecules.
The formula is d = MP/RT, where d is the gas's density in kilograms per liter, M is its molar mass in grams per mole, P is its pressure in atmospheric pressure units, and R is the gas law constant. The equation demonstrates that the molar mass increases as gas density increases. The pressure and temperature parameters for the gas determine the gas's density. Gas can dramatically alter its volume with a change in pressure due to its strong compressibility. Therefore, changes in density (at low pressure) can be substantial.
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Balance the following equations
a.H2+O2 -> H2O
b.ZnS + O2 -> ZnO + SO2
Answer:
a. 2H2 + O2--> 2H2O
b. 2ZnS +3O2-->2ZnO +2SO2
Explanation:
a.
note:
(when you put coefficients before the elements or the compounds you should multiply it by each element and the number that's on its right...
so if it's 2H2O
that is 2xH2 which is 4 hydrogen atoms
and 2 x O which is 2 oxygen atoms )
......
on the left side of the equation
there are two atoms of oxygen
but on the right side there's only one atom
so in order to balance them you have to put 2 as a coefficient for H2O
H2+O2 ->2H2O
so now you have 2 hydrogen atoms on the left side and 4 on the right side
you put 2 as a coefficient for H2
and now
there's 4 hydrogen atoms on both sides
and 2 oxygen atoms on both sides
b.
you do the same here
ZnS + O2 -> ZnO + SO2
2 oxygen atoms ---> 3 oxygen atoms
ZnS + 2O2 -> ZnO + SO2
4 oxygen atoms ---> 3 oxygen atoms
ZnS + 2O2 -> 2ZnO + SO2
4 oxygen atoms ---> 4 oxygen atoms
but
1 Zn ---> 2Zn
2ZnS + 2O2 -> 2ZnO + SO2
2S --> 1S
2ZnS + 2O2 -> 2ZnO + 2SO2
2S--> 2S
but
4O---> 6O
2ZnS + 3O2 -> 2ZnO + 2SO2
The solid xy decomposes into gaseous x and y: xy(s) m x(g) + y(g) kp = 4. 1 (at 0 °c) if the reaction is carried out in a 22. 4 l container, which initial amounts of x and y will result in the formation of solid xy?
The initial amounts of x and y required to form solid xy are 1 mol of x and 1 mol of y.
What is initial amount?The initial amount is the starting point for any financial transaction.
In order to calculate the initial amounts of x and y that will result in the formation of solid xy, the following equation must be used:
nx = ny * (4.1/kp)
where nx and ny are the moles of x and y, respectively, and kp is the equilibrium constant of the reaction.
Given the information provided, we can calculate the moles of x and y:
nx = ny * (4.1/4.1) = ny
ny = (22.4 L * 1 mol/22.4 L) = 1 mol
Therefore, nx = 1 mol and ny = 1 mol.
This means that if the reaction is carried out in a 22.4 L container, the initial amounts of x and y required to form solid xy are 1 mol of x and 1 mol of y.
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how many carbon atoms are in 2.12 mol of propane. how many hydrogen atoms are in 2.12 mol of propane
There are 5,944 carbon atoms in 2.12 moles of propane, and 15,528 hydrogen atoms in 2.12 moles of propane.
What is carbon?
Carbon is an element that occurs in nature and is essential for life. It is the fourth most abundant element in the universe and is present in all living organisms. Carbon exists in many different forms, including graphite, diamond, amorphous carbon, and fullerenes. Carbon is a key component of organic molecules, which are the building blocks of life. Carbon also plays an important role in the global carbon cycle.
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Please help. 100 points
Answer:
Term
Liquid C) takes the shape and volume of an entire container
Plasma A) charged particles that do not have a definite shape or volume
Solid B) has a fixed volume and shape
Gas D) assumes the shape of the part of the container from the bottom up
How can you tell which metal is more reactive?
The reactivity of metals depends upon their position in the periodic table and their nature of undergoing chemical reactions.
The primary difference between metals is the ease with which they undergo chemical reactions. The elements toward the bottom left corner of the periodic table are the metals that are the most active in the sense of being the most reactive. Such as alkali metals like Lithium, sodium, and potassium all react with water, thus they are reactive in nature than the metals belonging to alkaline earth metals. The nature of more reactivity of alkali metals is due to larger atomic radius and low ionization energies and they have only one valence electron in its outermost shell.
Thus, the reactivity of metals depends upon their position in the periodic table and their nature of undergoing chemical reactions.
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Write the expression for the solubility product constant for:Ca3(PO4)2 (s) 3Ca2+ (aq) + 2PO43- (aq)
The solubility product constant (Ksp) for a substance is the equilibrium constant for the reaction between the dissolved ions of the substance and its solid form. In the case of Ca3(PO4)2, the equation for the reaction in water is: Ca3(PO4)2 (s) ↔ 3Ca2+ (aq) + 2PO43- (aq)
The solubility product constant, Ksp, for this reaction is represented by the equation:
Ksp = [Ca2+]^3 * [PO43-]^2Where [Ca2+] represents the concentration of calcium ions in molarity and [PO43-] represents the concentration of phosphate ions in molarity.
Solubility refers to the maximum amount of a substance that can dissolve in a given solvent at a given temperature and pressure. For example, the solubility of sugar in water is the maximum amount of sugar that can dissolve in water at a given temperature and pressure. The solubility of a substance can be influenced by temperature, pressure, and the presence of other dissolved substances.
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Iodine Monochloride reacts reversibly with Chlorine to form Iodine Trichloride, What will be the color of the equilibrium mixture
Answer:
Yellow
Explanation:
The color of the equilibrium mixture of Iodine Monochloride and Chlorine is yellow. When the mixture is heated, it becomes darker brown in color.
Match each item with the correct statement below.
Column A
1. Fluorine, bromine, or iodine
2. An element found in Group 1 of the periodic table
3. Sodium or cesium:
4. An element found in Group 17:
5. Magnesium or barium:
6. An element found in Group 2:
An element found in Group 2
Column B
a. Alkali metal
b. Alkaline earth metal
c. Halogen
Answer:
Explanation:
Flourine, bromine or iodine --> HalogenAn element found in group 1 of the periodic table --> Alkali metalSodium or cesium --> Alkali metalAn element found in group 17 --> HalogenMagnesium or Barium --> Alkaline earth metalAn elment found in group 2 --> Alkaline earth metalWhat process do orcas use oxygen for?
The process orcas uses the oxygen is from the blowholes. the blow holes are situated on the top of of the head and it uses oxygen from their.
The whales and the humans uses the lungs for the respiration or to get oxygen required for the breathing. the orcas uses the oxygen from the blow holes situated at the top of the head. The orcas lives under the water and when the orcas dive in the water they have ability to hold the breath for at the time . but this is not good for the health . it is be very stressful for the body.
Thus, the process do the orcas uses oxygen for the intake is the from the blow holes.
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Which of the following is the strongest type of interaction that occurs between the atoms within the circled areas of the two molecules represented above? A) Polar covalent bond B) Nonpolar covalent bond C) Hydrogen bond D) London dispersion forces
The strongest type of interaction that occurs between the atoms is hydrogen bond.(option c)
A hydrogen atom that is bound to a highly electronegative atom and another highly electronegative atom that is close by interact with one another to form hydrogen bonds, which are an unique kind of attractive intermolecular interactions. This process is known as hydrogen bonding.
As a result of hydrogen bonding, a hydrogen atom simultaneously forms a covalent bond with one electronegative atom and a hydrogen bond with the other. These are the prerequisites for hydrogen bonding:
1.A strongly electronegative atom connected to the hydrogen atom must be present in the molecule. The degree of polarization of the molecule increases with increasing electronegativity.
2.The electronegative atom should have a tiny size. The strength of the electrostatic attraction increases with decreasing size.
So, the hydrogen bonding is the strongest bond.
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A student dissolved 0.178 grams of a solid monoprotic acid in water and then titrated it. They then performed the same calculation as you just did in question 2 to find the moles and they found that 0.00685 moles were neutralized. What is the molar mass of the unknown acid that was dissolved? (Hint: What are the units for molar mass?)
Mole measure the number of elementary entities of a given substance that are present in a given sample. Therefore, 25.98g/mol is the molar mass of the unknown acid that was dissolved.
What is mole?The SI unit of amount of substance in chemistry is mole. The mole is used to measure the quantity or amount of substance. We know one mole of any element contains 6.022×10²³ atoms which is also called Avogadro number.
Mathematically,
mole =given mass ÷ molar mass
Molar mass of unknown acid= ?
mass of unknown acid= 0.178 grams
moles of unknown acid= 0.00685 moles
Substituting the values in above formula we get
0.00685 = 0.178 ÷ molar mass
molar mass=25.98g/mol
Therefore, 25.98g/mol is the molar mass of the unknown acid that was dissolved.
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Use the drawing to help explain why gas pressure decreases when gas is removed from acontainer with a fixed volume
When gas is removed from a container with a fixed volume, the number of gas particles decreases, so there are fewer collisions and thus less pressure.
Additionally, the remaining gas particles have more space to move around, which also leads to a decrease in pressure. This can be visualized in the drawing by the decrease in the number of gas particles and the increased distance between them as gas is removed from the container.
As the gas particles decrease, there are fewer particles to collide with the walls of the container and therefore less force is exerted on the walls. This results in a decrease in the pressure inside the container.
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For the homogeneous solution consisting of KCl and H2O, indicate the type of forces that are involved. Check all that apply. View Available Hint(s) dipole-dipole forces ion-dipole forces dispersion forces hydrogen bonding Submit Previous Answers X Incorrect; Try Again; 9 attempts remaining
For the homogeneous solution consisting of KCl and H₂O, the type of forces that are involved is the dipole-dipole forces, the ion-dipole forces dispersion forces, the hydrogen bonding.
In the homogeneous solution if the two compounds are KCl and H₂O, they both polar and the forces involved are dipole - dipole forces and the dispersion forces. the forces present in between the water molecules is the hydrogen bonding. the forces in between the K⁺ and the Cl⁻ present is the ion - dipole forces,
Thus the all the four forces present in the homogeneous solution of the KCl and H₂O that is the dipole-dipole forces, the ion-dipole forces, the dispersion forces, and the hydrogen bonding.
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18) The vinegar was used to remove the shell form the raw egg. What other effect(s) did the vinegar have on the egg
The vinegar also caused the egg white to become more acidic, making it easier to separate from the yolk. Additionally, the vinegar helped preserve the egg by preventing bacteria from growing on the eggshell.
What is bacteria?Bacteria are microscopic organisms that exist virtually everywhere in nature. They range in size from 0.2 to 0.8 micrometers and can be found in soil, water, air, and even inside other organisms. Bacteria can reproduce rapidly, and some species can form biofilms that make them resistant to antibiotics. Bacteria can have beneficial roles in food production, soil fertility, and human and animal health. They can also cause diseases, such as cholera, meningitis, and tuberculosis. Bacteria are able to adapt quickly to changing environments and can become resistant to antibiotics.
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a sample of n2o gas has a density of 3.10 g/l at 298 k.what must be the pressure of the gas (in mmhg)?
To determine the pressure of a gas, we need to use the ideal gas law, which states that PV = nRT, where P is pressure, V is volume, n is the number of moles, R is the ideal gas constant, and T is the temperature in Kelvin.
We can re-arrange the ideal gas law to solve for pressure:
P = (nRT) / V
We are given that the density of the gas is 3.10 g/L, which we can use to calculate the volume of the gas. Density is defined as mass/volume, so we can rearrange the equation to find volume:
V = mass/density
We know the density is 3.10 g/L, and the mass is n * molar mass of N2O.
Molar mass of N2O = (14.01 + 2 * 16.00) g/mol = 44.01 g/mol
The volume of the gas is:
V = mass / density = n * molar mass of N2O / 3.10 g/L
Now we have all the information needed to use the ideal gas law to determine the pressure of the gas.
We are given that the temperature of the gas is 298K.
We can use the ideal gas constant R = 0.0821 Latm/molK
Plugging in the known values:
P = (nRT) / V = (n * 0.0821 Latm/molK * 298K) / (n * molar mass of N2O / 3.10 g/L)
P = (0.0821 * 298) / (44.01 / 3.10) atm
To convert the pressure in atm to mmHg, we need to multiply the pressure by 760 (1 atm = 760 mmHg)
P = (0.0821 * 298) / (44.01 / 3.10) * 760 mmHg
The pressure of the N2O gas is approximately 739.07 mmHg at 298K and density of 3.10 g/L.
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How popular is hydroelectric power?
Hydroelectric power is one of the oldest and most widely used renewable sources of energy.
Globally we see that hydropower is by far the largest modern renewable source. Every country's top priority is to generate hydroelectric power so they have to rely less on nuclear and coal power plants.
Hydroelectric power is generated by using the elevation difference, created by a dam or diversion-like structure of water flowing in on one side and out, far below, on the other side.
If we talk about some countries, Hydropower currently generates 31.5% of total U.S. renewable electricity generation.
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Lead absorption is decreased by the presence of ______ in the body. a) calcium and vitamin D b) calcium and iron c) iron and selenium
Answer: Correct option is B . calcium and iron decrease the absorption of lead in the body.
Explanation: calcium and iron decrease the absorption of lead in the body without affecting its solubility,probably by competing for shared absorptive receptors in the intestinal mucosa. The total body burden of lead does not affect lead absorption. Thus, lead does not have a feedback mechanism which limits absorption.