Answer:
From the reaction stoichiometry, 2 moles of Ca produces 2 moles of CaO. Thus, the number of moles of Ca is the same as that of CaO. Therefore, n = 0.16892 mol for CaO. Hence, 9.47 grams of calcium oxide are produced.Explain how to determine the total number of elements in a chemical formula
To determine the total number of elements in a chemical formula is being able to recognise the elements of the chemical formula.
What is an element?An element is defined as the chemical substance that cannot further be divided by any chemical process into smaller particles.
A chemical formula is a representation for a chemical compound or molecules which contains one or more elements with the number of atoms attached as a subscript.
An example of a chemical formula is NaCl. This chemical formula contains one element of sodium (Na) and one element of chlorine (Cl).
In order to determine the total number of elements in a chemical formula, the elements should be recognised and the subscript attached to the element shows the number of atoms of the element found in that particular formula.
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Who was the Russian chemist that arranged the elements of the periodic table in order of increasing atomic mass?
Answer:Dmitri Mendeleev
Explanation:
How do you determine how many significant figures to report in an addition or subtraction
problem?
Answer:
For addition and subtraction use the following rules:
1. Count the number of significant figures in the decimal portion ONLY of each number in the problem
2. Add or subtract in the normal fashion
3. Your final answer may have no more significant figures to the right of the decimal than the LEAST number of significant figures in any number in the problem.
Explanation:
The table gets its shape from the of the atoms
O properties
O odor
O color
O size
A rectangular piece of fabric with a length of 1.20 meters and a width of 0.85 meters must be divided into twelve, equal sized units for forensic sampling purposes. What are the dimensions of the twelve smaller portions?
The dimensions of the twelve smaller portions of the rectangular piece of fabric will be:
length = 0.1 mwidth = 0.85 mWhat will be the dimensions of the twelve smaller portions of the rectangular piece of fabric?The dimensions of the twelve smaller portions of the rectangular piece of fabric will be determined below as follows:
Dimension of the original piece of fabric is given as;
length = 1.20 meters and
width = 0.85 meters
The number of divisions of the fabric will be 12 equal parts
The multiples of 12 are 1, 2, 3, 4, 6, 12
Using the multiples to determine the dimensions of the twelve smaller portions:
12 and 1
Length = 1.2 / 12 = 0.1 m
width = 0.85 / 1 = 0.85 m
6 and 2
Length = 1.2 / 6 = 0.2 m
width = 0.85 / 2 = 0.425 m
4 and 3
Length = 1.2 / 4 = 0.3 m
width = 0.85 / 3 = 0.283 m
Therefore, the multiples 12 and 1 are the best match.
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what could you do to increase the electric force between to charged particles by a factor of 16
In other to increase the electric force between two charged particles by a factor of 16, the charged particle is increased by 16.
What is Electric force?This is referred to as the repulsive or attractive interaction between any two charged bodies and we should note that like poles repel and unlike poles attract.
One of the charged particle has to be increased by 16 for there to be an increase in the electric force between the particles by a factor of 16 and it can seen below:
F1/ F2 = kq1q2/r² / 16kq1q2 / r² where f is force, q is the charge and r is distance between charges.
F1 / F2 = 1/16
F2 = 16F1
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If a piston affecting 0.5 m² with 5 N force, what is the pressure put by the piston on the air inside?
Answer:
20
Explanation:
Pressure = Force / Area of Piston
0.5x0.5=0.25
5/0.25=20
----------------------------------------------------
If that answer doesn't work then try not squaring the 0.5
5/0.5=10
a sample of an ideal gas at 1.00 atm and a volume of 1.52 l was placed in a weighted balloon and dropped into the ocean. as the sample descended, the water pressure compressed the balloon and reduced its volume. when the pressure had increased to 70.0 atm, what was the volume of the sample? assume that the temperature was held constant.
The volume of the balloon when the balloon descended down in the water becomes 0.0217 Liters.
We know, from the Boyle's Law,
If the temperature of a gas is kept constant, the pressure of the gas and the volume of the gas becomes inversely proportional to each other.
So, we can write,
P₁V₁ = P₂V₂
Where,
P₁ is the initial pressure of the gas,
V₁ is the initial volume of the gas,
P₂ is the final pressure of the gas,
V₂ is the final volume of the gas.
According to the given condition, the initial volume of the ideal gas was 1.52 L and the initial pressure of the gas is 1 atm and the final pressure of the gas is 70 atm while the final volume is unknown,
So,
1.52 x 1 = V₂ x 70
V₂ = 0.0217 Liters.
The final Volume of the gas is 0.0217 Liters.
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The diagram shows an example of convection.
A picture of a clear pot of boiling water on a stove. There is an arrow pointing at the flame.
Which label belongs on the arrow?
From the diagram showing an example of convection, the label that belongs on the arrow is cooler water sinks while hotter water rises.
What are convection currents?Convection currents are currents that are set up by particles of a substance that transfer heat by the process of convection.
Convection is a form of heat transfer in which the particle of the substance transferring heat move from one point to another transferring heat as they move.
Convection is one of the three processes of heat transfer. The two other processes of heat transfer are conduction and radiation.
In the diagram shown, the heat transfer process show is convection.
The heat supplied by the flame is transferred from the bottom of the pot to the top by the movement of the water molecules. Heated water molecules move up while cold water molecules move down to replace them, thus, setting up a convection current.
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The atomic number of aluminum is 13. What is the correct designation of the electron configuration of aluminum?.
Answer:
Its 1s22s22p63s23p1 ik it looks a lil goofy but i think its right
Explanation:
does a 700 nm photon have more or less energy than a 400 nm photon? more less correct: your answer is correct. by what factor more (or less)? enter your answer as e700 nm e400 nm . e700 nm e400 nm
It is the 400 nm photon that has the greater energy by a factor of 1.77.
What is the wavelength?We know that the wavelength has to do with the horizontal distance that is covered by a wave. We know that the longer the distance that is covered then the weaker the wave. In other words, the wavelength of the wave is inversely proportional to the to the energy of the wave. The greater the wavelength, the lesser the energy.
Let us now find the energy of each of the wavelengths;
E = hc/λ
E = energy of the light
h = Plank's constant
c = speed of light
λ = wavelength
For the 700 nm photon;
E = 6.6 * 10^-34 * 3 * 10^8/ 700 * 10^-9
E = 2.8 * 10^-19 J
For the 400 nm photon;
E = 6.6 * 10^-34 * 3 * 10^8/ 400 * 10^-9
E= 4.95 * 10^-19 J
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please help tommorow exam. ill give brainly. please explain this
Explanation:
from the equation, we can understand that the mixture of these two substances formed a solid precipitate(Pbl2) which was yellow and a colourless liquid( 2KNO3)Try and visualize yellow cute particles dancing in a colourless liquid and you are trying to remove them from itJust like sieving rice from water, u use a filter paper to sieve them from the liquidOnce you pass the solution through the filter paper the solid particles won't pass through but remain on the filter paper. This will now be called filtrate while the liquid remaining is the residueFiltration is a seprating technique used for mixture containing liquid an solid precipitatesBest of luck in your exams!!!pyrazole has two nitrogens (labeled 1 and 2). which of the nitrogens will react first with an acid? explain your answer and support it with any relevant structures.
To solve this questions we need to know the heterocyclic compounds and little bit about resonance. Therefore the nitrogen which is labelled 2 will react first with acid.
What is heterocyclic compound?Heterocyclic compounds are those cyclic organic compounds that contains hetero atoms in place of carbon like N,S and O.
Pyrazole contains has structure just like pyrrole the Nitrogen which is labelled 1 that is NH act like nitrogen of pyrrole and the nitrogen that is labelled as 2 act like nitrogen of pyridine.
The electron of NH is involved in resonance, it is not free to give its electron to hydrogen ion from acid. So the nitrogen which is like nitrogen of pyridine will take hydrogen ion from acid first.
Therefore the nitrogen which is labelled 2 will react first with acid.
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help please!
What pressure will be required for neon at 30°C to have the same density as nitrogen at 20°C and 1.0 atm?
Is "Honey with water" a homogeneous or heterogeneous mixture? explain why?
Answer: Homogenous mixture
Mixing honey with water will give you a homogenous mixture. It is uniform and even, as the honey particles are distributed equally throughout the water.
hope it helps, mark as brainliest.
How many grams of water are required to change the temperature of water from 25.0 oC to 35.0 oC when 4,000.0 joules of energy are released?
The mass of water required to change the temperature of water from 25.0°C to 35.0°C when 4,000 joules of energy are released is 95.6g.
How to calculate mass?The mass of a substance in a calorimetry procedure can be calculated by using the following formula:
Q = mc∆T
Where;
Q = quantity of heat absorbed or releasedm = mass of substancec = specific heat capacity∆T = change in temperatureAccording to this question, a sample of water is changed from 25.0°C to 35.0°C when 4,000 joules of energy are released. The mass of the water sample is as follows:
4000 = m × 4.184 × 10
4000 = 41.84m
m = 95.6g
Therefore, 95.6 grams is the mass of the water sample.
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11) A sample of gas has a volume of 823.7 mL and a pressure of 351.8 torr. What volume (in mL) will the gas occupy at 752.9 torr if the temperature of the gas doesn't change? Keep the answer with one decimal place
Answer:
384.9 mL.
Explanation:
What is given?
Volume 1 (V1) = 823.7 mL.
Pressure 1 (P1) = 351.8 torr.
Pressure 2 (P2) = 752.9 torr.
What do we need? Volume 2 (V2).
Step-by-step solution:
This is a Boyle's Law problem. Boyle's law states that the volume of a given mass of gas varies inversely with the pressure when the temperature is kept constant. An inverse relationship is described in this way. As one variable increases in value, the other variable decreases.
The formula of the law is:
[tex]P_1V_1=P_2V_2.[/tex]Where P is pressure and V is volume. We want to find volume 2, 'V2'. So let's solve for 'V2' and replace the given data that we have in the new formula:
[tex]V_2=\frac{P_1V_1}{P_2}=\frac{351.8\text{ torr}\cdot823.7\text{ mL}}{752.9\text{ torr}}=384.882\text{ mL}\approx384.9\text{ mL.}[/tex]The new volumewill be 3384.9 mL You can note as the pressure is increasing, the volume is decreasing.
the concentration of magnesium inside a cell is 0.26%. the concentration of magnesium in the surrounding fluid is 0.18%. how could the cell obtain more magnesium?
The cell obtain more magnesium through Active transport.
What is Active transport?Active transport refers to the movement of molecules or ions across a cell membrane against the concentration gradient from a location of lower concentration to a region of higher concentration. Cellular energy is needed for active transport in order to achieve this movement. Adenosine triphosphate (ATP)-based primary active transport and electrochemical gradient-based secondary active transport are the two different forms of active transport.Active transportation uses include:
Bacterial phagocytosis by macrophages.Ca2+ ion expulsion from cardiac muscle cells.Amino acid movement via the intestinal epithelium in the human intestine.secretion of proteins from diverse cells, including enzymes, peptide hormones, and antibodies.White blood cell defense against invasive illnesses.Active transport employs cellular energy to move molecules against a gradient, polar repulsion, or other resistance, as opposed to passive transport, which relies on the kinetic energy and inherent entropy of molecules traveling down a gradientThe accumulation of large concentrations of substances that the cell requires, such as ions, glucose, and amino acids, is typically linked to active transport.To learn more about Active transport, refer to https://brainly.com/question/25802833
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Which polymer are synthetic
Answer:
Examples of synthetic polymers include nylon, polyethylene, polyester, Teflon, and epoxy.
Select a full set of quantum numbers for the following.
(a) the outermost electron in an K atom
n = 4; l = 0; ml = 0; ms = +1/2
n = 3; l = 1; ml = 1; ms = −1/2
n = 4; l = 1; ml = −1; ms = +1/2
n = 5; l = 0; ml = 0; ms = −1/2
(b) the electron gained when a Br atom becomes a Br − ion
n = 3; l = 2; ml = −1; ms = +1/2
n = 4; l = 2; ml = 2; ms = +1/2
n = 5; l = 1; ml = 0; ms = −1/2
n = 4; l = 1; ml = 1; ms = −1/2
(c) the electron lost when a Fr atom ionizes
n = 7; l = 0; ml = 1; ms = −1/2
n = 6; l = 1; ml = −1; ms = +1/2
n = 6; l = 1; ml = 0; ms = −1/2
n = 7; l = 0; ml = 0; ms = +1/2
(d) the highest energy electron in the ground-state C atom
n = 2; l = 1; ml = 0; ms = +1/2
n = 1; l = 0; ml = 0; ms = −1/2
n = 3; l = 2; ml = 1; ms = +1/2
n = 2; l = 2; ml = −1; ms = −1/2
(a) The full set of Quantum Numbers are n=4, l=0, ml=0, ms=+1/2
(b) The full set of Quantum numbers are ; n=4 , l= 1, ml= 1, ms= -1/2
(c) The full set of Quantum Numbers are n = 7; l = 0; ml = 0; ms = +1/2
(d) The full set of Quantum Numbers are n = 2; l = 1; ml = 0; ms = +1/2
Quantum Numbers is a set of numbers used to describe the position and energy of the electron in an atom. There are four quantum numbers namely, principal (n) , azimuthal(l), magnetic (ml) and spin quantum numbers (ms) .
(a) Potassium has atomic no Z=19
Electronic configuration of potassium= 1s² 2s²2p⁶ 3s² 4s¹
Outermost electron = 4s¹
n= 4 , l=0 since the outermost electron is in s orbital
and ml can change from -l to +l but if l= 0 because it is an s-orbital then ml must be zero too; m=0
ms can be either +1/2 or -1/2 depending on yhe spin of electron, it does not matter in this case. So, ms= =1/2
The full set of Quantum Numbers are n=4, l=0, ml=0, ms=+1/
(b) Bromine has atomic number Z= 35 and Br⁻ has atomic number= 36
Electronic configuration for bromine when an electron is gained
= (Ar) 3d¹⁰ 4s² 4p⁶
The electron the bromine atom gains to form bromide makes bromide have the same electronic configuration as the neon gas krypton. Krypton's electron configuration ends in 4p⁶. . The 4 is the n-value and the l-value is 1, which is a p-orbital. Since the p-orbital is filled, the last subshell ml is filled and it has a value of +1. The last electron filled in an orbital always has an ms = -1/2
The full set of quantum numbers are; n=4 , l= 1, ml= 1, ms= -1/2
(c) Fr has an atomic number = 87 ( Rn)7s¹
Electronic configuration for an electron lost in Fr atom= 1s² 2s²2p⁶ 3s²3p⁶ 3d¹⁰4s² 4p⁶ 4d¹⁰ 5s² 5p⁶ 4f¹
Therefore, for lost electron the outermost electron is in 7s⁰ shell.
n= 7, l=0 as the outermost electron is in s orbital and therfore ml= 0 ans ms= +1/2
Full set of quantum numbers are n = 7; l = 0; ml = 0; ms = +1/2
(d) carbon has atomic number Z=6
Electronic configuration = 1s² 2s² 2p²
In the ground state highest energy principal quantum no n=2
l= 1 as electron is in p orbital , ml=0 and ms= +1/2
full set of quantum numbers are= n = 2; l = 1; ml = 0; ms = +1/2
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suppose you analyze a 32.4 g sample of bleach and determine that there are 3.06 g of sodium hypochlorite present. what is the percent of sodium hypochlorite in the bleach sample? type answer:
The percent of sodium hypochlorite in the bleach sample is calculated to be 9.44% if 3.06 g of sodium hypochlorite is present.
Percentage can be calculated by dividing a value by the total value and then multiplying the resultant by 100.
In this case, we can determine the percentage of sodium hypochlorite in the bleach sample by dividing the mass of sodium hypochlorite by the total mass of the sample and then multiplying the resultant by 100 as follows;
percent of sodium hypochlorite = (mass of sodium hypochlorite/mass of sample) × 100
As 3.06 g of sodium hypochlorite is present in 32.4 g of the sample of bleach, substituting these values in the equation as follows;
percent of sodium hypochlorite = (3.06 ÷ 32.4) × 100
percent of sodium hypochlorite = 0.0944 × 100
percent of sodium hypochlorite = 9.44%
Therefore the percentage of sodium hypochlorite in the bleach sample is calculated to be 9.44%.
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Explain the effect of an enzyme on activation energy of a reaction.
Answer:
Enzymes act as catalysts, accelerating the chemical reaction by lowering the activation energy. Activation energy is the energy needed for the particles to react. Enzymes come out of the reaction unchanged.
Explanation:
Why is reactivity with oxygen a chemical property?
The reactivity of a substance with oxygen is a chemical, not a physical property. The reason it is called a chemical property is that it relies on its electron configuration to determine how it behaves around other substances.
What is a chemical property?A chemical property is a property of any material that becomes apparent during or after a chemical reaction; that is, any quality that can only be determined by changing the chemical properties of a substance.
Oxygen is a very reactive element, is highly paramagnetic and readily combines with other elements. One of the most important chemical properties of oxygen is that it promotes combustion. Even at room temperature, oxygen binds to elements and forms e.g. rust.
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a gas reacts with a solid that is present in large chunks, then the reaction is run again with the solid pulverized. how does the increase in the surface area of the solid affect the rate of its reactoi
An increase in the surface area of the solid will increase the rate of the reaction.
The reaction rate will be influenced by the solid's surface area if one of the reactants is solid. This is due to the fact that the two kinds of molecules can only collide at the liquid-solid interface, also known as on the surface of the solid. The reaction rate will rise due to a more significant interaction of the surface areas between the two molecules when the solid is pulverized into a gas. If a reactant has a larger surface area: The other reactant is exposed to more particles. Particles are more likely to collide, which results in more successful collisions per second this will influence the reaction speed to increase.
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Indicate the acid-base pairs for each of the following reactions:a) HClO3 + H2O <=> H3O + + ClO3-b) HSeO4 - + NH3 <=> NH4 + + SeO4 2-C) HCO3- + OH - <=> CO3 2- + H2OD) C5H5NH + + H2O <=> C5H5N + H3O+
Acid - base pairs.
Arrhenius theory, says, that acids are substances that dissociate in water to yield electrically charged atoms or molecules, called ions, one of which is a hydrogen ion (H+), and that bases ionize in water to yield hydroxide ions (OH−).
It is now known that the hydrogen ion cannot exist alone in water solution; rather, it exists in a combined state with a water molecule, as the hydronium ion (H3O+). In practice the hydronium ion is still customarily referred to as the hydrogen ion.
----------------------------------------------------------------------------------------------------------------
a) HClO3 + H2O <=> H3O + + ClO3-
HClO3 is the acid, ClO3- is the base (acid-base pair)
H2O acepts that H+ from the HClO3, and becomes H3O+
H2O is a base, H3O+ is the acid (acid-base pair)
----------------------------------------------------------------------------------------------------------------
b) HSeO4 - + NH3 <=> NH4 + + SeO4 2-
Here HSeO4 - can free one H so it would be the acid, and SeO4 2- is the base.
NH3 receives H+ from acid, so it is the base, and NH4+ is the acid.
---------------------------------------------------------------------------------------------------------------
c) HCO3- + OH - <=> CO3 2- + H2O
HCO3- gives away one H, so it is the acid, and CO3 2- is the base
(HCO3-,CO3 2-) acid-base pair.
OH- receives the H+ and becomes H2O. OH- is the base and H2O acid.
H2O can be acid and base, remember that. In this case it is the acid.
---------------------------------------------------------------------------------------------------------------
d) C5H5NH + + H2O <=> C5H5N- + H3O+
C5H5NH has the H, but on the right it doesn't, so it would be th acid. C5H5N- is the base.
H2O here is a base, because it receives the H+, and becomes H3O+ (the acid).
---------------------------------------------------------------------------------------------------------------
a) cite the major differences between activation and concentration polarizations. (b) under what conditions is activation polarization rate controlling? (c) under what conditions is concentration polarization rate controlling?
Activation polarization is occuring due to the evolution or deposition of some gases taking place in a redox reaction. Concentration polarization occurs between two electrodes when uneven distribution of ions occurs in the boundary.
What is polarization?Polarization is the process of charge separation between two species or the potential difference occurred due to the concentration gradient.
The two types of polarization occuring are activation polarization and concentration polarization. In activation polarization there occurs difference by the accumulation of gases.
For example the evolution of gases from the hydrogen electrode immersed in an electrolyte causes a polarization between the two electrodes.
In concentration polarization, there will be a concentration gradient of ions in the boundary of two electrodes occured due the electroanalytical reaction.
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Calcium chloride can be used to
melt ice during winter. A 750 mL
sample of melted snow was
collected and the calcium chloride
analyzed. The sample contained
1.54 g of calcium chloride.
Calculate the percent by mass
concentration of calcium chloride
The percent by mass concentration of calcium chloride is 0.20%
What is mass concentration?
Mass concentration, which is a quantity to measure this same concentration of a solute in the solution, is similar to molar concentration, molality, and mass fraction. It reveals how much of a solute there is in a certain volume of solution. Let's use coffee as an example to try to understand it. By combining coffee, sugar, and hot water, a straightforward instant coffee can be made. 10 g of coffee and 5 g of sugar are required to make a typical cup (250 mL) of coffee. Depending on individual preferences, the sum may change. We will need twice as much of the ingredients—20 g of caffeine and 10 g of sugar—to make two cups (500 mL).
When the mass of a solute as well as the mass of a solution are given, the mass percent is employed to express this same concentration of a solution:
Mass Percent=Mass of Solute/Mass of Solution×100%
% by mass = mass of substance/ mass of solution * 100 %
= 1.54/750*100 % = 0.20%
The percent by mass concentration of calcium chloride is 0.20%
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When you put aspirated spinach leaf disks in a beaker of sodium bicarbonate and place them in different colors of light, some disks float faster & more abundantly than others dependent on what color, if any, they were in. What made them able to float?.
The release of O₂( oxygen gas) from the process of photosynthesis is made disks to be able to float.
What is Photosynthesis?Photosynthesis can be described as the process in which green plants manufacture their food in the presence of sunlight which is trapped by the chlorophyll of the leaves. They are also called primary producers and they use compounds such as water and carbon dioxide.
The spinach leaf disks intake carbon dioxide from a sodium bicarbonate solution and sink to the bottom of a beaker. When the beaker is exposed to light, the disks use carbon dioxide gas and water to produce oxygen gas and glucose. Oxygen gas released from the leaves due to photosynthesis forms tiny bubbles that make the leaves float.
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help pleasee! will
give brainliest +80 pts
Answer: type the compound into your search bar then it should tell you what it is for 3. you should look up "what is the formula for -----" same thing for #4
Explanation:
Answer:
2.a. germanium tetrahydride
2.b. dinitrogen tetrabromide
2.c. diphosphorus pentasulfide
2.d. selenium dioxide
2.e. nitrogen trihydride
2.f. silicon dioxide
3.a. PO3
3.b. SiCl4
3.c. N2O5
3.e. N2O4
3.f. CO
4.a CO2
4.b. SF6
4.c. N2Cl4
4.d. CI4
4.e. PF5
4.f. P2O5
****All numbers are subscripts, please do not write them as is, but to the bottom right of them like shown in the options from question 2.
Explanation:
To name covalent compounds (NM+NM), we use prefixes.
To name covalent compounds goes as follows:
First, name the first element in the formula the normal name it has (ex. Nitrogen, Oxygen). If the first element is present more than once shown by a subscript, use a prefix that will indicate how many there are present (ex. mono, di, tri).
Next, name the second element in the compound using prefixes aswell if present more than once. These elements though, will end with -ide instead of their original name (ex. monoxide, dibromide, trichloride).
it has been found that ddt in the soil decomposes by a first-order reaction with a half-life of 12.0 years. how long would it take ddt in a soil sample to decompose from a concentration of 195 ppbm (parts per billion by mass) to 15 ppbm?
The ddt in the soil with half-life of 12 years needs 44.4 years to decompose.
We need to know about the half-life of the radioactive elements to solve this problem. The radioactive element will decay over time and follow the equation
N = No(1/2)^(t/t'')
where N is the final quantity, No is the initial quantity, λ is the decaying constant, t is time and t'' is the half-life of a radioactive element.
From the question above, we know that
t'' = 12 yr
N = 15 ppbm
No = 195
By substituting the given parameter, we can calculate the required for decomposing
N = No(1/2)^(t/t'')
15 = 195(1/2)^(t/12)
1/13 = (0.5) ^ (t/12)
t/12 = ⁰'⁵log(1/13)
t/12 = 3.7
t = 44.4 years
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