No, not all antigens are foreign substances.
An antigen is any substance that can trigger an immune response, including the production of antibodies. Some antigens are naturally present in the body and are called "self" antigens which are usually not harmful, but in some cases, the immune system can mistakenly recognize them as foreign and attack them which can lead to autoimmune diseases.
Antigens bind together with antibodies and promote the elimination of harmful pathogens present in the body. They alert other parts of the immune system to take over which helps to neutralize the threat from pathogens.
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Using the balanced equation
how many
3Ba+Al2(SO4)3-->2Al+3BaSO4,
grams of aluminum will be produced if 1.0 g of Ba react with 1.80 g of
Al2(SO4)3?
O.14
0.26
0.28
O.13
Grams of aluminum that will be produced if 1.0 g of Ba react with 1.80 g of Al2(SO4)3 will be 0.28g Al. Hence option c) is correct.
What is balanced equation?A balanced equation is a chemical equation where mass is conserved and there are equal numbers of atoms of each elements on both the sides of equation.
Given, 1.80 g of Al2(SO4)3 and 1.0 g of Ba
So, (1.8 g)/(341.96 g) = 0.00526 moles of Al2(SO4)3
And, 1 mole = 341.96g Al2(SO4)3
Now, (0.00526 moles of Al2(SO4)3)*(2 moles of Al)
= 0.01052 moles of Al
So, (0.01052 moles of Al)*(27 grams of Al)
= 0.28g Al
Hence, option c is correct.
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What is the molecular weight of MgCl2
The molecular weight of MgCl₂ is 94 g/mol.
What is molecular weight?This refers to the total mass of a compound. It is equivalent to the sum of the individual atomic masses of each atom in the molecule.
Steps to determine the molecular formula of the molecule.
Determine the atomic mass of each element in the molecule.Multiply each element's atomic mass by the number of atoms of that element in the molecule. This number is represented by the subscript next to the element symbol in the molecular formula.Add these values together for each different atom in the molecule.The total will be the molecular mass of the compound.Atomic number of Cl =17
Atomic number of Mg = 12
Mass number of Cl = 35
Mass number of Mg = 24
Calculating the molecular weight of MgCl₂
MgCl₂
=(12* 2) + (35*2)
= 24 + 70
= 94 g/mol.
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when might the BAC of a dead body be misleading or unhelpful
Answer: Blood alcohol levels at autopsy are valid up to 48 hours after death when simple principles are observed in the collection and storage of samples. Alcohol levels in samples of blood taken from the intact heart are as significant as levels of blood from the femoral veins.
Explanation:
Answer:
If the victim was submerged in water
Explanation:
hydrates (1 question)
6) When 10.000 g of a hydrated compound are analyzed in the laboratory, the following analysis is obtained: 1.425 g of water, 5.462 g of lead, 1.266 g of carbon, 1.687 g of oxygen, and 0.160 of hydrogen. What are the name and formula of the compound?
The name and formula of the compound can be determined by analyzing the data given in the question. Based on the information provided, the compound contains lead, carbon, oxygen, and hydrogen. The molecular formula for the compound can be determined by adding up the number of atoms of each element present.
From the data given, the compound contains 1.266 g of carbon, which is equivalent to 1.266/12.01 = 0.105 mol of carbon atoms. It also contains 5.462 g of lead, which is equivalent to 5.462/207.2 = 0.026 mol of lead atoms. The compound also contains 1.687 g of oxygen, which is equivalent to 1.687/16.00 = 0.105 mol of oxygen atoms, and 0.160 g of hydrogen, which is equivalent to 0.160/1.01 = 0.158 mol of hydrogen atoms.
The molecular formula for the compound is therefore Pb(C2H2O2). However, it is also mentioned that the compound is hydrated, which means that it contains water. The 1.425 g of water present in the compound is equivalent to 1.425/18.02 = 0.079 mol of water molecules. The compound 1 likely Pb(C2H2O2)·xH2O, where x represents the number of water molecules present in the compound.
How many moles of magnesium atoms react with 1 mole of oxygen molecules?
1 mole of magnesium atoms will react with 2 moles of oxygen molecules. This is because the chemical equation for the reaction between magnesium and oxygen is: Mg + O2 → MgO.
What is chemical equation?A chemical equation is a symbolic representation of a chemical reaction, showing the reactants (starting materials) on the left side and the products (resulting substances) on the right side. The symbols used to represent the reactants and products are chemical formulas, which use the symbols of the elements in the reaction. The arrow between the reactants and products indicates the type of reaction taking place. The coefficients next to the symbols and formulae of entities indicate the number of moles of each species that are involved in the reaction. The overall reaction is balanced when the number of atoms of each element on the left side of the equation is equal to the number of atoms of that element on the right side of the equation.
This equation shows that for every 1 mole of magnesium atoms, 2 moles of oxygen molecules are required for the reaction to take place. Therefore, 1 mole of magnesium atoms will react with 2 moles of oxygen molecules.
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Let us assume that Cd(OH)2(s) is completely insoluble, which signifies that the precipitation reaction with NaOH(aq) (presented in the transition) would go to completion.
Cd2+(aq)+2NaOH(aq) → Cd(OH)2(s)+2Na+(aq)
If you had a 0.300 L solution containing 0.0220 M of Cd2+(aq) , and you wished to add enough 1.25 M NaOH(aq) to precipitate all of the metal, what is the minimum amount of the NaOH(aq) solution you would need to add? Assume that the NaOH(aq) solution is the only source of OH−(aq) for the precipitation.
Answer:
The minimum amount of NaOH(aq) solution needed to add is 0.0560 L. This can be calculated by using the following equation:
Moles of Cd2+ = 0.0220 M x 0.300 L = 0.0066 mol
Moles of NaOH = 0.0066 mol x 2 = 0.0132 mol
Volume of NaOH = 0.0132 mol/1.25 M = 0.0560 L
Explanation:
Map of structure of an Atom?
Atoms are made up of a very tiny, positively charged nucleus that is encircled by a sea of negatively charged electrons. Despite often being less than a tenth of an atom's size, the nucleus makes up more than 99.9% of the atom's mass.
What is the structure of an Atom?The term "atomic structure" describes the structure of an atom, which has a nucleus (centre) that contains both protons (positively charged) and neutrons (neutral). The centre of the nucleus is circled by the negatively charged electrons.
Positively charged protons, negatively charged electrons, and neutral neutrons make up the three types of subatomic particles that make up an atom. Nearly equal in mass, protons and neutrons are found in the dense nucleus of the atom.
Thus, Atoms are made up of a very tiny, positively charged nucleus that is encircled by a sea of negatively charged electrons.
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To write a number in scientific notation:
a.)move the decimal place until there is a number between one and ten
b.) Write x 10 to the right of the number
C.)count the number of times the decimal had to move and write this as an exponent
D) if it was a BIG number, it should be positive if it was a small number (less than 1) it should be negative
3.00 x 108 m/s should be written in scientific notation. Medical Notation (numbers less than 1.0) Add a decimal place after the decimal, to the right. To the left of the decimal point, there should only be one number. The brand-new number ranges from 1.0000 to 9.9999.
How to write a number in scientific notation?For the purpose of providing an exact result, certain elements of scientific notation must be included. In scientific notation, all numbers have the format "m x 10n. Important components for determining the scientific notation include the following:
Decimal: You move the decimal a specific number of times to the right or left of the coefficient to discover the scientific notation until it becomes a number equal to or greater than one and less than 10.
Coefficient: To calculate this value, the decimal point must move a predetermined amount of times. An amount that is one or larger and less than ten is referred to as a coefficient.
Base: The base number is always 10. The exponent comes into play when multiplying to arrive at the final solution.
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1.5 billion plastic bottles are bought world-wide each day. These bottles are about 9.8 inches in length (1 meter = 3.28 ft). If the Earth's diameter is about 40,000 km at the equator, how many times could you encircle the Earth with the bottles laid end to end?
Hint: Your DA table should have 5 conversion factors
The number of times 1.5 billion plastic bottles laid end to end could encircle the Earth would be 9.34 times.
Dimensional analysisSize of bottle = 9.8 inches
1 foot = 12 inches
Size of 9.8 inches bottles in foot = 0.8167 ft
Also, 3.28 ft = 1 meter
0.8167 ft = 0.8167x1/3.28
= 0.2490 meter
1000 meter = 1 km
0.2490 meter = 0.2490/1000
= 0.000249 km
Total number of bottles = 1.5 billion
Total length of 1.5 billion bottles laid end to end in kilometers = 1,500,000,000 x 0.000249 = 373,500 km
Number of times the bottle could encircle the earth = 373,500/40000
= 9.34 times
Thus, 1.5 billion plastic bottles would encircle the Earth about 9.34 times if laid end to end.
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Which of these is an example of a physical property?
A. Iron combines with oxygen to rust.
B. Potassium reacts in water to form a base.
C. Sodium metal is soft and malleable.
D. Sodium ignites when placed in water.
Remember: all EM waves travel at the same __________. The equation for speed is __________ times the __________. So, for the answer to always be 300,000km/s, as one number goes __________, the other must go __________. All EM waves are __________. The higher the __________, the more __________ in the wave.
All the EM waves travel at the same speed. The equation for speed is frequency (v) times the wavelength (λ). Speed of light equals 300000 km/s. Hence one number goes to 3 × 10⁸ m and other number is 1 s⁻¹.
What is an electromagnetic wave ?Electromagnetic waves are waves moving without a medium through vacuum. They are accompanied with an electric field and magnetic field. The speed of an electromagnetic wave is the product its wavelength and frequency.
c = νλ
Therefore, the given passage can be filled as follows:
All the EM waves travel at the same speed. The equation for speed is frequency (v) times the wavelength (λ). Speed of light equals 300000 km/s. Hence one number goes to 3 × 10⁸ m and other number is 1 s⁻¹.
All EM waves are energetic. The higher the frequency the more energy in the wave.
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List all the metals in the alkaline earth metals group
Answer:
beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba), and radium (Ra).
Alkaline earth metals are those that have two valence electrons in their outermost shell.
Barium (Ba), Radium (Ra), Strontium (Sr), Magnesium (Mg), Calcium (Ca), and Beryllium (Be) are the six alkaline earth metals.
By donating their outermost electrons, they take on the noble gas electron configuration, which increases their stability. When electrons are transferred to an atom with an electronegative charge, the alkaline earth metals get a positive charge.
The second column of the periodic table contains alkaline earth metals, which are very reactive metals. These metals are the building blocks of the entire world. These metals are typically found as sulfates in nature.
A few examples of minerals are gypsum, calcium sulfate, epsomite, magnesium sulfate, barite, and barium sulfate.
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the bond between br atoms in a br2 molecule is
Answer:
COVALENT
Explanation:
covalent and is formed by the sharing of two valence electrons.
I understand how a change in the size of the moon jellies' resource population can change the number of births in the moon jelly population.
Responses
Explain your answer choice.
A change in the size of the moon jellies' resource population can change the number of births in the moon jelly population because the big size of the resources can produce more births.
How do moon jellies reproduce?When there is more energy storage molecules present in the moon jellies, they can reproduce more, in more births. Fewer deaths would also lead to the jelly population increasing. The sea turtle population, and the moon jellies consumer population is also decreased.
There must be a change to the birth rate or the death rate in the moon jelly population. Within a population, organisms are born and dying continuously. If the number of births and deaths in a given time interval are equal, then the population size will remain stable.
So we can conclude that a large population of resources will lead to more births.
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What is a flame test used for?
A. To identify an unknown sample by its emission spectrum
B. To determine the ionization energies of electrons
C. To remove impurities from a sample through burning
D. To identify an unknown sample by its melting point
The flame test used for to identify an unknown sample by its emission spectrum
What is the purpose of a flame test?A metal or metalloid ion discovered in an ionic compound can be identified, or at least its potential identification, using the flame test, a qualitative chemical test. It's possible for the compound to emit a distinctive colour that may be seen with the unaided eye if it's placed in a gas burner's flame. To determine whether metal and metalloid ions are present in the sample, chemists employ a qualitative examination known as a flame test. The metal ions heated in the gas burner don't all produce colour. The quickest and most straightforward method for determining whether group 1 metal ions are present in the chemical is a flame test. A wire or wooden splint is dipped into a sample solution or coated with the substance to be tested.To learn more about flame test refers to:
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Answer: to identify an unknown sample by its emission spectrum
Explanation:
Average Volume of A Drop. 15 Drops for 1 ML
Note that if the water volume (ML) in a graduated cylinder is 30.0 and the volume of a drop of water is 1.00 and the number of drops is 15, the average drop volume (ML) is 2.0 mL.
What is average drop volume?Average drop volume is a measurement of a droplet's average volume. It is employed in a wide range of applications, including laboratory experimentation, medical research, and medication delivery systems.
It aids in deciding the proper amount of liquid to utilize in a certain condition. It also aids in the creation of novel pharmaceuticals and assuring exact and constant dosing in medical treatments.
You may calculate the average drop volume by dividing the total amount of water (30.0 mL) by the number of drops (15). That is to say:
(30.0 mL divided by 15 drops = 2.0 mL/drop)
Hence where the number of drops is 15mL and the volume of one drop is 1.00mL, the average Volume of a Drop is 2.0mL
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Which statement about the elements in Group 0 is correct?
Tick () one box.
A. All elements in the group are very reactive.
B. All elements in the group form negative ions.
C. The boiling points increase down the group.
D. The relative atomic masses (Ar) decrease down the group.
The boiling points increase down the group.Thus, option C is the answer.
Group 0, also known as the noble gases, is a group of chemical elements in the periodic table. These elements are all characterized by having a full valence shell of electrons, which gives them little tendency to gain or lose electrons and makes them generally unreactive. As a result, the elements in Group 0 are not very reactive and do not form many compounds.
The boiling points of the elements in Group 0 generally increase as you go down the group. This trend is due to the increasing atomic radius of the elements as you go down the group. The larger the atomic radius, the more space there is between the atoms in a substance, and the more energy is required to overcome the attractive forces between the atoms. This results in a higher boiling point.
In contrast, the relative atomic masses (Ar) of the elements in Group 0 generally decrease as you go down the group. This is because the atomic radius increases as you go down the group, but the number of protons in the nucleus (and therefore the atomic mass) does not change significantly. As a result, the relative atomic mass decreases as the atomic radius increases.
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I need help please in this:(
Answer:
That would be A sir or Miss
Explanation: Tell me if I am wrong, Also hope this helped you!
what is a difference between mass and volume
Answer:
Volume is how much space the object is taking up, whereas mass is the measurement of the amount of matter in the object.
Explanation:
Please help me fill in the blanks
Electrons first occupy the position in lowest possible energy.
orbital diagrams:-
The higher the energy level, the Third energy the electrons in that level have. On the orbital diagram, fill in the boxes to label the representations of an orbital and a sublevel. 2 electrons can occupy a single orbital, and these electrons have Opposite spin. Within a sublevel, all the orbitals fill with one electron, each of which has the Positive spin before a second electron fills any of the orbitals.
what is Orbital?
Each energy position is made up of areas known as an orbital. An orbital is an area of probability in which electrons can be set up. Each energy position, except for the first, has further than one orbital. Each orbital has a specific shape.
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Which one of the following pairs are the common languages of science?
A. English & Latin
B. Mathematics & Units
C. Standards & Measures
D. English & French
Answer:
a whole new world too be into
Explanation:
During the electrolysis of molten sodium chloride, which ion discharges at the anode?
Answer:
it should be chlorine gas
Explanation:
A 1.00 L volume of HCl reacted completely with 2.00 L of 1.50 M Ca(OH)2 according to the balanced chemical equation below. 2HCl + Ca(OH)2 Right arrow. CaCl2 + 2H2O What was the molarity of the HCl solution? 0.375 M 1.50 M 3.00 M 6.00 M
Mass can be calculated by using moles which can be further calculated from multiplication of Molarity to volume. Therefore, the molarity of the HCl solution is 3M. the correct option is option C.
What is molarity?
Molarity can be calculated by dividing number of moles of solute by volume of solution in litre. Molarity is affected by temperature. Its unit is mole/litre. It measure the concentration of any solute in a solution.
Other concentration terms are molality, normality and mole fraction. Molarity can be used to find out the ionic strength of any solution
Mathematically,
2HCl + Ca(OH)[tex]_2[/tex] [tex]\rightarrow[/tex] CaCl[tex]_2[/tex] + 2H[tex]_2[/tex]O
Molarity of HCL× Volume of HCL=Molarity of Ca(OH)[tex]_2[/tex] ×Volume of Ca(OH)[tex]_2[/tex]
Molarity of HCL× 1.00 L=1.50 M× 2.00 L
Molarity =3M
Therefore, the molarity of the HCl solution is 3M. the correct option is option C.
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1. what are the methods of vegetative propagation
2.give examples of organisms exihibiting each type
3.tubers-definitio example potatoes
science subject
Natural vegetative propagation uses bulbils, aerial shoots, roots, underground stems, and subaerial stems. Utilizing unique vegetative components, artificial vegetative propagation is accomplished.
What is vegetative propagation, and how does it work?The production and growth of a new plant through asexual means or from a plant fragment is known as vegetative propagation. There is no gamete production or fertilization throughout the process of propagation.
What are some instances of vegetative tuber propagation?In this procedure, tubers—modified roots—grow into new plants. In some plant species, adventitious buds even grow on the roots. If the correct circumstances are present, these buds develop into new plants or sprouts. Sweet potato and dahlia are two examples.
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The heat of vaporization for benzaldehyde is 48.8 kJ/mol, and its normal boiling point is 451.0 K. Use this information to determine benzaldehyde's vapor pressure (in torr) at 49.5°C. Report your answer to three significant digits.
The vapor pressure at 49.5 °C is:
DP = 48.8 kJ/mol / 8.314 J/mol*K * (1/451.0 K - 1/322.65 K) * 49.5
DP = 0.24 torr (approx)
The vapor pressure of benzaldehyde at 49.5°C is approximately 0.24 torr.
How to calculate heat of vaporization?The heat of vaporization (ΔHvap) and the normal boiling point (Tb) can be used to determine the vapor pressure of a liquid at a given temperature using the Clausius-Clapeyron equation. The Clausius-Clapeyron equation states that the change in vapor pressure (DP) with temperature (DT) is directly proportional to the heat of vaporization (ΔHvap) and inversely proportional to the absolute temperature (T) in kelvin.
DP/DT = ΔHvap / R * (1/T)
where R is the gas constant.
We can use this equation to solve for the vapor pressure of benzaldehyde at 49.5°C.
First, convert 49.5°C to kelvin:
T = 49.5°C + 273.15 = 322.65 K
Next, we need to use the Clausius-Clapeyron equation to solve for vapor pressure at a temperature T and the normal boiling point Tb:
DP/DT = ΔHvap / R * (1/T) = ΔHvap / R * (1/Tb - 1/T)
DP = ΔHvap / R * (1/Tb - 1/T) * DT
The vapor pressure at 49.5 °C is:
DP = 48.8 kJ/mol / 8.314 J/mol*K * (1/451.0 K - 1/322.65 K) * 49.5
DP = 0.24 torr (approx)
The vapor pressure of benzaldehyde at 49.5°C is approximately 0.24 torr.
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The vapor pressure of the benzaldehyde is 196 torr.
What is the vapor pressure?We know that the vapor pressure would have to do with the ease that we can use to convert the substance that is in question from liquid to gas. When we have two substances that are at different temperatures than we have;
ln(P2/P1) = -ΔH/R(1/T1 - 1/T2)
P2 = final pressure
P1 = initial pressure
R = gas constant
T1 = initial temperature
T2 = final temperature
Thus;
ln(P2/1) = -48.8* 10^3/8.314(1/451 - 1/322.5)
lnP2 = -5869.6(0.0022 - 0.0031)
lnP2 = 5.28
P2 =e^5.28
P2 = 196 torr
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URGENT PLEASE HELP
1) The following balanced chemical equations are for based on the combustions of various fuels. Calculate the heats of combustion for each reaction
a. C2H5OH(l) + 3O2(g) à 2CO2(g) + 3H2O(g)
b. 2C4H10(g) + 13O2(g) à 8CO2(g) + 10H2O(g)
c. C3H8(g) + 5O2(g) à 3CO2(g) + 4H2O(g)
2) Express the heats of combustion from the above reactions as energy changes per mole of fuel combusted. State the reason why energy changes are often expressed per mole of reactant.
3) An Electric Generator burns gasoline to produce electricity. The balanced equation is below:
2C8H18(l) + 25O2(g) à 16CO2(g) + 18H2O(g)
a. Calculate the energy change for the burning of gasoline.
b. If the generator produces 2000kJ of electrical energy for every mole of gasoline combusted calculate the efficiency of the generator.
Answer:
Explanation:
1) The following balanced chemical equations are for based on the combustions of various fuels. Calculate the heats of combustion for each reaction a. C₂H₂OH + ...
help me i need it asap
Which example is a biotic factor of an aquarium ecosystem?
plastic plants placed in the gravel
algae growing on the glass
rock structure
gravel on the bottom of the aquarium
Which examples are an abiotic factor of an aquarium ecosystem? Select all that apply.
rock structure
temperature of the water
amount of algae on the glass
number of fish
Which example describes an abiotic factor interacting with a biotic factor?
The temperature of the air affecting the wind direction
Water eroding a rock
Cows eating nearby grass
The amount of sunlight affecting the growth of a plant.
Students in Ms. Brown's class are making observations in the garden outside of the school. They make a list of all the abiotic and biotic factors in their notebook. Part of the list is below:
Gravel
Grass
Butterfly
Sunflower
Bird feeder
Flowerpots
Which items on the list are a part of the garden ecosystem?
Grass, butterfly, sunflower
None of the listed items are a part of the ecosystem
All the listed items are part of the ecosystem
Gravel, bird feeder, flowerpots
The biotic factor of an aquarium ecosystem is algae growing on the glass.
The abiotic factors of an aquarium ecosystem are rock structure, temperature of the water, and amount of sunlight.
The example that describes an abiotic factor interacting with a biotic factor is the amount of sunlight affecting the growth of a plant.
All the listed items in Ms. Brown's class, including gravel, grass, butterfly, sunflower, bird feeder, and flowerpots, are a part of the garden ecosystem.
What is an ecosystem?An ecosystem is a community of living organisms (biotic factors) interacting with each other and with their physical environment (abiotic factors) in a specific area. It includes all the living and non-living components of the environment that interact with each other. Examples of ecosystems include a coral reef, a forest, a desert, and even an aquarium or a garden. Ecosystems can be large or small and can be found on land or in water. They are essential for the survival of living organisms as they provide food, shelter, and other resources necessary for life.
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Which electron configuration represents a transition element?
01s²2s²2p³
01522s22p635²
1s²2s²2p63s²3p64s²3d7
1s22s22p63s23p64s²3d¹04p4
The electronic configuration which represents a transition element is 1s²2s²2p⁶3s²3p⁶4s²3d⁷
What is a transition element?Transition elements are placed between the metallic S-block elements and nonmetallic P-block elements in the periodic table. They are D-block elements and have features similar to both metals and nonmetals, to some extent. This is why they are called transition elements.
One remarkable feature of these elements happens during the addition of electrons to them. Contrary to S and P-block elements, electrons are added to the penultimate shell, not the last shell. These elements often feature partially filled d-orbitals and have multiple oxidation states.
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Please show all of your work, I need to understand all steps:
A student collected time (t) and concentration ([A]) data at
295 K for the reaction 2A→B. These time and concentration data are shown in the table to the right. The student then plotted graphs of [A] versus t (Figure 1) , ln[A] versus t (Figure 2) , and 1/[A] versus t (Figure 3) .
Figure 1:
t (s) (A)(M) ln(A) 1/ (A)
0.00 0.500 −0.693 2.00
20.0 0.389 −0.944 2.57
40.0 0.303 −1.19 3.30
60.0 0.236 −1.44 4.24
80.0 0.184 −1.69 5.43
i.) What is the rate of the reaction?
ii.) What is the value of the rate constant for this reaction?
iii.)
Next, the student ran the same reaction at a different temperature and measured a different reaction rate, with the following results:
T(K) k(s-1)
295 0.0125
325 0.0357
What is the activation energy of this reaction?
Express your answer to three significant figures and include the appropriate units.
Answer:
a because the x and y value is the same
What is the number of moles of K+ ions are present in 250 mL of a 0.4M KCl solution?
a. 0.1 mol c. 0.62 mol
b. 0.16 mol d. 1.6 mol
The concentration terms are molality, normality and mole fraction. Molarity can be used to find out the ionic strength of any solution. Therefore, 0.025 is the number of moles of K+ ions are present in 250 mL of a 0.4M KCl solution.
What is molarity?Molarity can be calculated by dividing number of moles of solute by volume of solution in litre. Molarity is affected by temperature. Its unit is mole/liter. It measure the concentration of any solute in a solution.
Mathematically,
Molarity= number of moles of solute/volume of solution in litre
Substituting values in equation 1
0.4M=number of moles of solute/0.25
number of moles of solute=0.025moles
Therefore, 0.025 is the number of moles of K+ ions are present in 250 mL of a 0.4M KCl solution.
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