Answer:
9 tablets.
Explanation:
2.21gg is 2210mg
2210/250= 8.84
An initial sample of iridium-192 is prepared pure, with no contamination of other isotopes. After a certain amount of time, one finds that the sample includes 4.4% osmium-192. How much time has passed since the initial sample was prepared?
Hence, 8.12 days had passed because the initial sample is made according to the isotopes.
Simply put, what is an isotope?Atoms that have the same protons and neutrons but different quantities of neutrons are called isotopes. Despite having almost equal chemical properties, they have different masses, which affects their physical characteristics.
This allows us to write: N/N0 (= 0.956 = (1/2)(t/T).
When we take the logarithmic of both sides, we obtain:
t/T*log(1/2) = log(0.956) = log(0.956)
When we solve for t/T, we get:
t/T = log(0.956)/log(1/2)=0.110
By dividing both sides by T, we can finally find t:
t = (0.110) (0.110) * T
Iridium-192 has a 73.83-day half-life. Therefore:
t = (0.110) (0.110) 8.12 days divided by 73.83 days.
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To be considered a cognitive psychologist, you typically need what degree?
All cognitive psychologists work in academia performing research. T OR F
If you want to pursue a career in cognitive psychology, it is important to participate in a DIS during your undergraduate career. T or F
A Ph.D. or Psy.D. in psychology with a cognitive psychology concentration is normally required to be categorized as a cognitive psychologist. Thus, the choice is between a Ph.D. and a Psy.D.
All cognitive psychologists work in academia performing research. T OR FFalse. While most cognitive psychologists do their study in academic institutions, some may work in governmental, nonprofit, or commercial organizations.
If you want to pursue a career in cognitive psychology, it is important to participate in a DIS during your undergraduate career. T or FFalse. It is not compulsory to pursue a career in cognitive psychology, even though taking part in a Directed Independent Study (DIS) during your undergraduate studies may be advantageous to get research experience in the field. Other options for developing one's research abilities and experience include working in a lab or doing an internship.
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What is pasteurisation
Castration is the method of storing milk there was discovered by Louis Pasteur
Explanation:
Castration is the method of storing milk there was discovered by Louis Pasteur
Which of these is an example of an agricultural use for radiation?
A. making heavy isotopes to find new elements.
B. irradiating wheat to kill fungus.
C. diagnostic procedures that image inside the body, such as a PET scan.
D. locating leaks in a water line in a building.
Irradiating wheat to kill fungus is an example of an agricultural use for radiation.
option B.
What is irradiation?Irradiation of agricultural products is a process in which ionizing radiation (such as gamma rays or electron beams) is used to eliminate harmful organisms such as bacteria, viruses, fungi, and insects that may be present in the products. The process involves exposing the product to a controlled dose of radiation, which kills or sterilizes the harmful organisms without significantly affecting the quality, taste, or nutritional value of the product.
Thus, irradiation can be used to eliminate pests and diseases in agricultural products, including grains, fruits, and vegetables. Irradiation of wheat can be used to eliminate fungi, insects, and other harmful organisms, improving the shelf life and quality of the product.
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classification, dietry source,biochemical function and specific deficiency disease of vitamins
Answer:
Vitamins are essential organic compounds that are required in small amounts to maintain various physiological processes in the human body. They are classified into two groups: fat-soluble vitamins (A, D, E, and K) and water-soluble vitamins (B-complex vitamins and vitamin C).
The dietary sources and biochemical functions of each vitamin are as follows:
Vitamin A - Found in liver, fish, eggs, and dairy products. It is required for vision, immune function, and growth.
Vitamin D - Found in fatty fish, eggs, and fortified dairy products. It is required for bone health and helps the body absorb calcium.
Vitamin E - Found in nuts, seeds, and vegetable oils. It acts as an antioxidant and helps protect cells from damage.
Vitamin K - Found in green leafy vegetables and certain fruits. It is required for blood clotting.
B-complex vitamins - Found in meat, fish, poultry, whole grains, and fortified cereals. They play various roles in energy production, nervous system function, and red blood cell formation. Examples include:
Vitamin B1 (Thiamine) - Required for energy production and nerve function. Deficiency can cause beriberi.
Vitamin B2 (Riboflavin) - Required for energy production and cell growth. Deficiency can cause skin and eye disorders.
Vitamin B3 (Niacin) - Required for energy production and proper digestion. Deficiency can cause pellagra.
Vitamin B5 (Pantothenic Acid) - Required for energy production and hormone synthesis. Deficiency is rare.
Vitamin B6 (Pyridoxine) - Required for protein metabolism and immune function. Deficiency can cause anemia and neurological problems.
Vitamin B7 (Biotin) - Required for energy production and proper metabolism. Deficiency is rare.
Vitamin B9 (Folate) - Required for cell growth and development. Deficiency can cause anemia and birth defects.
Vitamin B12 (Cobalamin) - Required for nerve function and DNA synthesis. Deficiency can cause anemia and neurological problems.
Vitamin C - Found in citrus fruits, strawberries, kiwi, and bell peppers. It acts as an antioxidant and is required for collagen synthesis. Deficiency can cause scurvy.
In summary, vitamins are essential nutrients required for a range of functions in the body. They can be obtained through a balanced diet, and deficiency of any vitamin can lead to various health problems.
Explanation:
Water has a specific heat of 4.184 J/g°C. If the temperature of 250 g of
water changes from 22.9°C to 14.7°C, how much heat energy was removed
from the water?
A gaseous compound has a density of 1.50 g/L
at 27.1 °C
and 1.34 atm.
What is the molar mass of the compound?
Answer:
To find the molar mass of a gaseous compound given its density, temperature, and pressure, we can use the ideal gas law and the definition of density.
The ideal gas law is PV = nRT, where P is the pressure of the gas, V is the volume, n is the number of moles of the gas, R is the gas constant, and T is the temperature of the gas in Kelvin.
We can rearrange this equation to solve for the number of moles, n:
n = PV/RT
The density of a gas, d, is defined as the mass of the gas divided by its volume:
d = m/V
where m is the mass of the gas.
We can use the molar mass of the gas, M, to relate the mass of the gas to the number of moles:
m = nM
Combining these equations, we can solve for the molar mass of the gas:
M = m/n = (dV)/n = (dVRT)/P
Plugging in the given values, we get:
M = (1.50 g/L) x (0.08206 L·atm/mol·K) x (300.1 K) / (1.34 atm)
M = 64.4 g/mol
Therefore, the molar mass of the gaseous compound is approximately 64.4 g/mol.
Explanation:
A 550.0 mL sample of gas at 40.0 °C and 895 torr is transferred to a second vessel where the temperature is 0.0 °C and the pressure is 745 torr. What is the volume of the second vessel?
The volume of the second vessel is approximately 450 mL. In physics and chemistry, pressure is an important concept that is used to describe the behavior of gases, liquids, and solids under different conditions.
What is Pressure?
It is a scalar quantity and is expressed in units such as pascals (Pa), pounds per square inch (psi), atmospheres (atm), or torr. Pressure is created by the collision of particles (atoms or molecules) with the walls of a container, and it can be influenced by factors such as temperature, volume, and the number of particles present.
The first step is to use the combined gas law to relate the initial conditions to the final conditions:
(P1V1)/T1 = (P2V2)/T2
where P is pressure, V is volume, and T is temperature, with subscripts 1 and 2 representing the initial and final conditions, respectively.
Plugging in the given values, we get:
(895 torr)(550.0 mL)/(313.15 K) = (745 torr)(V2)/(273.15 K)
Solving for V2, we get:
V2 = (895 torr)(550.0 mL)/(313.15 K) * (273.15 K)/(745 torr) ≈ 450 mL
Therefore, the volume of the second vessel is approximately 450 mL.
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calculate the weight 'm' grams of 5.6L of chlorine gas cl2 at NTP.
The weight of 5.6 L of chlorine gas Cl₂ at NTP is 17.75 grams
How do i determine the weight of the chlorine gas at NTP?The volume of a gas at normal temperature and pressure, NTP, is given as
22.4 L = 1 mole of a gas
With the above information, we can obtain the weight (in grams) of the 5.6 L of chlorine gas Cl₂. This is shown below.
The following data were obtained from the question:
Volume chlorine gas, Cl₂ at NPT = 5.6 L1 mole of chlorine gas, Cl₂ = (2 × 35.5) = 71 gramsWeight of chlorine gas =?At normal temperature and pressure, NTP, the volume of chlorine gas is given as follow:
22.4 L = 1 mole of chlorine gas, Cl₂
22.4 L = 71 grams of chlorine gas, Cl₂
Therefore,
5.6 L = (5.6 L × 71 grams) / 22.4 L
5.6 L = 17.75 grams of chlorine gas, Cl₂
Thus, we can conclude from the above calculation that the weight of the gas at NTP is 17.75 grams
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How many moles of Argon are present in 11.2 grams of argon gas?
Answer:
0.280 moles
Explanation:
We can convert from grams to moles through molar mass.
Stoichiometry
Stoichiometry is the study of the relationship between quantities of substances. Part of stoichiometry is converting between different quantity measurements such as grams (g) and moles (mols).
One way to convert between g and mols is molar mass. Molar mass is the number of grams in one mole of a substance. Molar mass is a constant that can be found on periodic tables.
Conversion
First, we need to look at a periodic table and find that the molar mass of Argon (Ar) is 39.948 g/mol. To convert between units, set up a multiplication problem where the unwanted units (grams in this case) are in the numerator at one point and then in the denominator. Having the units in opposite positions allows the units to cancel out.
[tex]\frac{11.2g}{1} *\frac{1mol}{39.948g} =0.280mol[/tex]So, there are 0.280 moles of Argon in 11.2 grams. Note that this answer has been rounded according to significant figures rules.
A balloon filled with exhaled air has a volume of 16.0 L at 1.08 atm. If the balloon is perfectly elastic, what is the volume of the balloon if it is taken into the mountains where the pressure is is 0.877 atm and the temperature is the same.
Answer:
be at a pressure of 0.987 atm if the temperature remains constant? P, V₁ = P2 V2 ... A helium-filled balloon has a volume of 50.0L at 25.0°C and 1.08atm.
Explanation:
right
Calculate the number of moles of C2H6
(nC2H6
) in 7.93×1023
molecules of C2H6
According to the mole concept, there are 1.316 moles of ethane in 7.93×10²³ molecules of ethane.
What is a mole?Mole is defined as the unit of amount of substance . It is the quantity measure of amount of substance of how many elementary particles are present in a given substance.
It is defined as exactly 6.022×10²³ elementary entities. The elementary entity can be a molecule, atom ion depending on the type of substance. Amount of elementary entities in a mole is called as Avogadro's number.
Number of moles=number of molecules/Avogadro's number= 7.93×10²³/6.023×10²³=1.316
Thus, there are 1.316 moles of ethane in 7.93×10²³ molecules of ethane.
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A sample of potassium (K, found in Group 1) and a sample of iodine (I, found in Group 17) react, forming potassium iodide (KI), which is used to treat thyroid conditions. Complete the statements to describe this reaction. The reaction occurs because electrons are pulled away from the more | less electronegative element by the more | less electronegative element. The more electronegative element is found in Group 1 [ Group 17. The less electronegative element is found in Group 1 Group 17.
The words that complete the blanks are;
1) Less
2) More
3) Group 17
4) Group 1
What is electronegativity?Electronegativity is a measure of an atom's ability to attract electrons towards itself when it forms a chemical bond with another atom. It is a relative property, meaning that it is determined by comparing the electronegativities of two or more elements.
Electronegativity values are typically determined on a scale of 0 to 4, with 4 being the highest electronegativity value. Fluorine, the most electronegative element, has an electronegativity value of 4.0, while other elements have values that are lower than 4.0.
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Calculate the number of moles of Cu in 1.25x10^25 atoms of Cu
Answer: 1.25.173.
Explanation:just caluate
Lithium has an atomic mass of 6.941 amu. Lithium has two common isotopes.
Lithium has an atomic mass of 6.941 amu. Lithium has two common isotopes as lithium-6 and lithium-7.
What are isotopes?
Isotopes are the elements which have same atomic number but different mass number. For example - Carbon has three isotopes- C-12, C-13, C-14. If an element is found to have different isotopes in nature then it’s average atomic mass can be calculated as
Average atomic mass = (m×a + n×b) / (m+n)
Where a = Atomic mass of isotope A of element X
b = Atomic mass of isotope B of element X
A and B are present in m:n ratio in nature.
Therefore, Lithium has an atomic mass of 6.941 amu. Lithium has two common isotopes as lithium-6 and lithium-7.
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An object that is at rest will begin to move if which of the following is true?
The surface on which it rests is frictionless.
The mass of the object is sufficient.
Gravity on the object can be reduced.
Unbalanced forces act on the object.
Answer:
D. Unbalanced forces act on the object
Explanation:
Newton's First Law of Motion states that an object at rest will remain at rest unless acted on by an outside force.
the object will begin to move when unbalanced forces act on it
Explanation:
Newton's first law of motion states that 'a body or an object will continue to be in its state of rest until it's acted upon by an external force'
What is the water of crystallization for a hydrate composed of 45.1% water? The anhydrous salt has a mass of 178 amu.
The 8 anhydrοus salt has a mass οf 178 amu..
What is mοle?A mοle is the atοm's elementary particle, an iοn. The mοle οf the substance is always related tο the Avοgadrο number. The mοle is always assοciated with the weight οr mass οf the element οr substance. The standard unit οf a mοle is mοl. The mοle is a significant factοr οf the reactant and prοducts tο fοrm an equatiοn. A mοle calculates the atοm, iοn, and substance weighs.
The amοunt οf matter in a bοdy is referred tο as its mass. The kilοgrams is the kilοgrams, which is the SI unit οf mass (kg). Mass is defined as: Mass = Density /Vοlume.
mass οf water =45.1% = 45.1 g
means that 45.1 g οf water in 100 g salt
hence mass οf anhydrοus salt(As)= 100 g - 45.1 g = 54.9 g
mοlar mass οf anhydrοus salt (As) = 178 amu=178 g /mοl
mοlar mass οf water (H2O)=18.015 g /mοl
1st step:- Find mοl οf water
mοl οf water = mass οf water / mοlar mass οf water
= 45.1 g / 18.015 g /mοl
= 2.5035 mοl
2nd step:- find mοl οf Anhydrοus salt
mοl οf Anhydrοus salt (As) = mass οf anhydrοus salt / mοlar mass οf anhydrοus salt
= 54.9 g / 178 g /mοl
= 0.3084 mοl
3rd step:-calculate water οf crysatlisatiοn
= mοl οf water / mοl οf Anhydrοus salt
= 2.5035 mοl / 0.3084
= 8.118
= 8 (apprοx)
hence tοtal 8 mοl οf water present in Anhydrοus salt(As) = As*8H20
Therefοre, 8 anhydrοus salt has a mass οf 178 amu.
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what is the iupac name for the following compound? question 20 options: heptaneA. hexaneB. heptaneC. octaneD. nonane
Answer:
what is the IUPAC name for the following compound? question 20 options: heptane A. hexane B. heptane C. octane D. nonane
C. Octane
Explanation:
Can someone help explain how to solve this question? A 250 ml flask contains 0.75 miles of O2, 0.13 miles of N2, and enough moles of H2 that produces a partial pressure of 0.74 atm. The temperature of the gas mixture is 297k. Calculate the total pressure of the flask and calculate the mole fraction of H2.
Find the concentration of I in 0.10 M AgNO, saturated with AgI. Include activity coefficients in the solubility-product
expression. The Ksp of AgI is 8.3 x 10-17.
The concentration of I in 0.10 M AgNO, saturated with AgI in the solubility product is 8.3 x 10^-16 M.
Solubility product calculation.The solubility product expression for AgI is:
Ksp = [Ag+][I-]
At equilibrium, the concentration of Ag+ ions is equal to the solubility of AgI, which is equal to the molar solubility of AgI in 0.10 M AgNO3. Let's assume that the molar solubility of AgI is x. Then, the equilibrium concentrations of Ag+ and I- ions are:
[Ag+] = 0.10 M + x
[I-] = x
The solubility product expression can be written as:
Ksp =[tex]\sqrt{x}[/tex] ([Ag+] * [I-])
Substituting the equilibrium concentrations into the solubility product expression, we get:
Ksp = √(0.10 M + x) * (x)
Using the quadratic equation, we can solve for x:
Ksp =√ 8.3 x 10^-17
0.10 M is much greater than x, so we can assume that (0.10 M + x) ≈ 0.10 M
Ksp = (0.10 M) * (x)
x = Ksp / (0.10 M)
x = 8.3 x 10^-16
So, the molar solubility of AgI is 8.3 x 10^-16 M. Since the concentration of I- ions is equal to the solubility of AgI, the concentration of I- ions is also 8.3 x 10^-16 M.
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Which of the following is not an assumption in Bohr's theory. a) Energy is not dissipated when electrons move in an orbital b) Electrostatic force balances force tending to throw electron out of orbital c) Pairing of electrons reduces orbital stability d) Electrons move from one orbital to another by either absorbing or radiating energy
Answer: C
Explanation: The assumption that pairing of electrons reduces orbital stability is not part of Bohr's theory.
Bohr's theory of atomic structure mainly focuses on the behavior of electrons in the atom and makes several key assumptions:
a) Energy is not dissipated when electrons move in an orbital (postulate of quantization)
b) Electrostatic force balances force tending to throw electron out of orbital (Coulomb's law)
d) Electrons move from one orbital to another by either absorbing or radiating energy (postulate of transitions)
Therefore, the correct answer is option (c) Pairing of electrons reduces orbital stability.
Type your answer here:
Table 1. Measurements Taken from a Simulation of a [insert mass value] kg Ball Released from Various Heights on a Ramp
Mass of ball (kg) Drop height on-ramp (m) Potential energy (J) Time to travel 1.0 m (s) Speed (m/s) Kinetic energy (J)
0.5
1.0
1.5
2.0
2.5
3.0
Conclusions
1. What conclusions can you draw about how the amount of potential energy stored in a system changes as a ball is placed at varying heights on a ramp? Write an evidence-based claim.
Type your answer here:
2. What conclusions can you draw about how the final kinetic energy of a ball in a system changes as a ball is placed at varying heights on a ramp? Write an evidence-based claim.
Type your answer here:
3. Develop a model (diagram) that shows how different amounts of gravitational potential energy (GPE) are stored in the earth-ball system when the ball is raised to different heights on the ramp.
Type your answer here:
4. How did you use what you learned from the first part of the experiment to design a marble run?
Type your answer here:
I used the results from the first part of the experiment to design a marble run by understanding the principles of potential and kinetic energy.
What is kinetic energy?Kinetic energy is the energy of motion. It is the energy an object has due to its motion. When an object is moving, it has kinetic energy. This energy is dependent on the mass of the object and its velocity. Kinetic energy can be calculated by multiplying the mass of the object by the square of its velocity and then dividing the result by two. Kinetic energy is one of the two main types of energy, along with potential energy. It has the ability to cause change within a system, such as breaking chemical bonds. When an object is at rest, it does not have kinetic energy. However, as soon as it begins to move, it acquires kinetic energy. Kinetic energy can be changed or transferred from one object to another, or from one form to another.
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Which of these is an example of an agricultural use for radiation?
A. making heavy isotopes to find new elements.
B. irradiating wheat to kill fungus.
C. diagnostic procedures that image inside the body, such as a PET scan.
D. locating leaks in a water line in a building.
An example of an agricultural use for radiation is option B which is irradiating wheat to kill fungus is an example of an agricultural use for radiation.
Radiation in agriculture explained.Radiation in agriculture refers to the use of various forms of ionizing radiation (such as gamma rays, X-rays, and electron beams) for agricultural purposes. This includes using radiation to improve crop yield and quality, preserve food, and control pests and diseases. Radiation can also be used to induce mutations in plants, which can lead to the development of new varieties with desirable traits such as increased yield, disease resistance, and drought tolerance. Additionally, radiation can be used to sterilize soil and agricultural products, such as spices and herbs, to eliminate harmful pathogens and pests. Overall, the use of radiation in agriculture has the potential to improve food safety, increase productivity, and reduce waste in the agricultural industry.
Therefore, radiation can be used to kill harmful organisms such as fungi and bacteria that can cause disease and spoilage in crops, as well as to improve breeding and seed production in plants.
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Consider the balanced equation:
2 CH4 (g) + 3 O2 (g) + 2 NH3 ---> 2 HCN (g) + 6 H2O (g)
If 203.6 g of NH3 is reacted with excess CH4 and O2, what mass in grams of HCN is produced?
The mass (in grams) of HCN produced when 203.6 g of NH₃ reacts with excess CH₄ and O₂ is 323.4 g
How do I determine the mass of HCN produced?The mass of HCN produced when 203.6 g of NH₃ reacts with excess CH₄ and O₂ can be obtained as follow:
2CH₄(g) + 3O₂(g) + 2NH₃ -> 2HCN(g) + 6H₂O(g)
Molar mass of NH₃ = 17 g/molMass of NH₃ from the balanced equation = 2 × 17 = 34 g Molar mass of HCN = 27 g/molMass of HCN from the balanced equation = 2 × 27 = 54 gFrom the balanced equation above,
34 g of NH₃ reacted to produce 54 g of HCN
Therefore,
203.6 g of NH₃ will react to produce = (203.6 × 54) / 34 = 323.4 g of HCN
Thus, the mass of HCN produced is 323.4 g
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Please put the steps in order from 1-5 first correct answer gets Brainliest.
5. This energy is released with wavelengths and frequencies within the visible portion of the electromagnetic spectrum.
3. The excited state is not a stable configuration for the atom because there are lower energy
sublevels not filled, so e' eventually fall back to original energy levels (ground state)
1. Electrons start in the most stable arrangement, called the ground state
2. Electrons absorb energy from heat or electricity and move to a higher energy level, this is called the excited state
4. When they fall back, the electrons have to release the energy absorbed to
move to the excited state.
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Using a 500 mL beaker, a teacher stirred sugar into some water. The sugar seemed to disappear during the stirring process. The beaker was then placed on the teacher’s demonstration desk. A few days later all of the water evaporated, and sugar appeared in the bottom of the beaker. Which is the best evidence that no chemical reaction occurred? A.All the sugar evaporated. B.Sugar combined with water to form a new substance. C.Sugar is still in the beaker. D.All the sugar dissolved faster due to stirring by the teacher.
The best evidence that no chemical reaction occurred in the process described is that the sugar is still in the beaker after the water has evaporated. Therefore, the correct answer is C.
What is a chemical reaction?The chemical, known as the reactant, is changed into a new substance, the product, during a chemical reaction. Here, the atoms that make up the reactants are rearranged to form products. This is an irreversible process.
In the process described in the question, sugar was simply dissolved in water to form a sugar-water solution. This is a physical change, not a chemical change, because the sugar molecules remained intact and did not undergo a chemical reaction with the water molecules. The sugar molecules were simply dispersed throughout the water, making them invisible to the eye.
When the water evaporated, the sugar molecules were left behind and re-crystallized in the bottom of the beaker. This process did not involve a chemical reaction, only a physical change.
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Which of the following correctly describes delocalized valence electrons in a metal?
Group of answer choices
Valence electrons move from outer orbitals to inner orbitals of each atom.
Valence electrons move from inner orbitals to outer orbitals of each atom.
Valence electrons move between atoms in shared orbitals.
Valence elctrons move out of the orbitals and go into the air.
Valence electrons move between atoms in shared orbitals- correctly describes delocalized valence electrons in a metal
Why are valence electrons important and what do they do?
The outermost or valence shell electrons, known as valence electrons, are crucial because they shed light on an element's chemical characteristics and are the ones that are acquired, lost, or shared during a chemical reaction. In general, when an atom's outermost electron shell is complete, it is at its most stable and least reactive.
The number of valence electrons for neutral elements is the same as the number of the atom's main group. A periodic chart element's column can be used to determine its main group number. For instance, carbon, which belongs to group 4, has four external electrons.
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Find the ΔHr0 for the reaction : 2HCl(aq) + Ca(OH)2(s) → CaCl2(s) + 2H2O(l)
The standard enthalpy change of reaction for the given reaction is -46.9 kJ/mol. Since the enthalpy change is negative, it indicates that the reaction is exothermic and releases energy in the form of heat.
What is Enthalpy?
Enthalpy (H) is a thermodynamic property that describes the total heat content of a system at constant pressure. It is a measure of the internal energy of a system, which includes the energy required to create or destroy the system as well as the energy required to maintain its temperature and pressure.
The standard enthalpy change of reaction (ΔHr0) can be determined using the standard enthalpies of formation (ΔHf0) of the reactants and products.
2HCl(aq) + Ca(OH)2(s) → CaCl2(s) + 2H2O(l)
The standard enthalpy change of reaction can be calculated using the following equation:
ΔHr0 = Σ(nΔHf0(products)) - Σ(nΔHf0(reactants))
ΔHf0(HCl(aq)) = -167.2 kJ/mol
ΔHf0(Ca(OH)2(s)) = -986.1 kJ/mol
ΔHf0(CaCl2(s)) = -795.8 kJ/mol
ΔHf0(H2O(l)) = -285.8 kJ/mol
Substituting the values into the equation, we get:
ΔHr0 = [2(ΔHf0(H2O(l))) + ΔHf0(CaCl2(s))] - [2(ΔHf0(HCl(aq))) + ΔHf0(Ca(OH)2(s))]
ΔHr0 = [2(-285.8 kJ/mol) + (-795.8 kJ/mol)] - [2(-167.2 kJ/mol) + (-986.1 kJ/mol)]
ΔHr0 = (-571.6 kJ/mol - 795.8 kJ/mol) - (-334.4 kJ/mol - 986.1 kJ/mol)
ΔHr0 = -1367.4 kJ/mol + 1320.5 kJ/mol
ΔHr0 = -46.9 kJ/mol
Therefore, the standard enthalpy change of reaction for the given reaction is -46.9 kJ/mol. Since the enthalpy change is negative, it indicates that the reaction is exothermic and releases energy in the form of heat.
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What can you deduce about the molecular composition of the reactants in a chemical reaction with the following atomic masses?
Reactants: (12 + 1 + 1 + 1 + 1) + (24 +16) = 56 u
Stoichiometric amounts relate to the proportional amounts of reactants and products in a balanced chemical equation.
What transpires during a chemical reaction to the molecules of the reactants?
Only atoms from the reactants can wind up in the products of a chemical reaction. No atoms are annihilated or made into new ones. To create the products, the reactants come into contact with one another, the bonds between their atoms are broken, and the atoms then rearrange and establish new bonds.
The frequency of collisions between the two reactants will grow as the reactant concentration rises. There are times when collisions don't cause a response (atoms misaligned or insufficient energy, etc.). More collisions and reaction possibilities result from higher concentrations.
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Zn + 2HCI H2 + ZnCI2 caculate the grams of zinc chloride produced if .236 grams of zinc react completely
The grams of zinc chloride produced if .236 grams of zinc react completely is 0.492 grams
Grams calculation
The balanced chemical equation for the reaction is:
Zn + 2 HCl → H2 + ZnCl2
The molar mass of Zn is 65.38 g/mol and the molar mass of ZnCl2 is 136.29 g/mol.
To calculate the grams of zinc chloride produced, we first need to find the number of moles of zinc used in the reaction:
moles of Zn = mass of Zn / molar mass of Zn
moles of Zn = 0.236 g / 65.38 g/mol
moles of Zn = 0.00361 mol
From the balanced chemical equation, we can see that the stoichiometric ratio of Zn to ZnCl2 is 1:1. This means that 0.00361 mol of Zn will produce 0.00361 mol of ZnCl2.
To calculate the mass of ZnCl2 produced, we can use the following equation:
mass of ZnCl2 = moles of ZnCl2 x molar mass of ZnCl2
mass of ZnCl2 = 0.00361 mol x 136.29 g/mol
mass of ZnCl2 = 0.492 g
Therefore, if 0.236 grams of zinc react completely, 0.492 grams of zinc chloride will be produced.
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