Answer:
0.041 grams of carbon-14 remaining.
Explanation:
The half-life of carbon-14 is the time it takes for half of the original amount of carbon-14 to decay. In this case, the half-life of carbon-14 is 5,730 years. This means that after 5,730 years, half of the original amount of carbon-14 will remain, and half will have decayed.
In this problem, we are given that a fossilized tree branch originally contained 4.30 grams of C-14, and we are asked how much C-14 would be left after 50,000 years. To find this, we need to calculate how many half-lives have occurred over this time period, and then find the resulting amount of C-14.
We can use the formula N = N0 * (1/2)^(t/t1/2) to calculate the amount of C-14 after a given number of half-lives, where N0 is the initial amount of C-14, t is the total time elapsed, and t1/2 is the half-life of the substance.
Plugging in the given values, we get N = 4.30 g * (1/2)^(50000 years / 5730 years/half-life) = 0.041 g.
So, after 50,000 years, the tree branch will have 0.041 grams of carbon-14 remaining.
ALLEN
One of the main terms used in physics to describe the radioactive decay of a specific sample or element over a predetermined amount of time is half-life, also known as half-life period. After 50,000 years, the tree branch will have 0.041 grams of carbon-14 remaining.
What is half-life?A radioactive material's half-life is typically described as the amount of time it takes for one half of its atoms to decay or change into another substance. Ernest Rutherford made the first discovery of the theory in 1907. It is typically denoted by the letters Ug or t1/2.
Understanding half-lives is crucial because they allow you to determine if a sample of radioactive material is safe to handle. A sample is deemed safe when its radioactivity is below detection thresholds. Ten half-lives later, something occurs.
We can use the formula N = N0 * (1/2)^(t/t1/2)
N = 4.30 g * (1/2)^(50000 years / 5730 years/half-life) = 0.041 g.
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A student runs an experiment to figure out if the size of a wire changes how well it conducts electricity. She uses 5 different widths of copper wire and attaches each to a multimeter to measure
the resistance in the wires. The data collected is shown below.
Wire 1-12 Ohms
Wire 2-17 Ohms
Wire 3-9 Ohms
Wire 4-14 Ohms
Wire 5-6 Ohms
What is the independent variable in this experiment?
A. The multimeter.
B. The resistance values.
C. The material of the wires, copper.
D. The widths of the wires.
The independent variable is the the widths of the wires.
What is the independent variable?
In an experimental setup, the independent variable is the variable that is manipulated or changed by the researcher. It is also referred to as the "predictor variable" or the "explanatory variable."
The idea behind manipulating the independent variable is to observe its effect on another variable, which is called the dependent variable. The dependent variable is the variable that is thought to be affected by the independent variable.
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If you are inflating a balloon that has 0.0200 mol of Helium and a volume of 0.150 m3. How many moles of Helium are there if the new volume of the balloon is 0.90 m3?
__________moles Helium
The concept Avogadro's law is used here to determine the number of moles of Helium. The number of moles of He is 0.0033 mol.
What is Avogadro's law?The Avogadro's law states that equal volumes of all gases under similar conditions of temperature and pressure contain equal number of molecules. Mathematically it is expressed as:
V ∝ n
1m³ = 1000 L
0.150 m³ = 150 L
0.90 m³ = 900 L
For two different gases, equation is:
V₁n₁ = V₂n₂
n₂ = V₁n₁ / V₂
= 150 × 0.0200 / 900
= 0.0033 mol
Thus the number of moles of 'He' is 0.0033 mol.
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Each of the following are either a weak acid or a weak base that will partially ionize to form 2 ions. Complete the ionization equation for each.
HCN + H2O ⇌
HF + H2O ⇌
NH4OH + H2O ⇌
C5H5N + H2O ⇌
A weak acid or a weak base is a substance that partially ionizes to form two ions in aqueous solution.
What exactly do you mean by aqueous solution?
An aqueous solution is basically a solution in which the solvent is water. Aqueous solutions can contain salts, acids, bases and other compounds. These solutions are often used in chemistry, biology and medicine for a variety of purposes.
HCN + H2O ⇌ H+ + CN- (weak acid)
HF + H2O ⇌ H+ + F- (weak acid)
NH4OH + H2O ⇌ NH4+ + OH- (weak base)
C5H5N + H2O ⇌ H+ + C5H5N- (weak acid)
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How many grams of Mn are in 1.07x10^24 atoms
The mass (in grams) of Mn present in 1.07×10²⁴ atoms is 97.735 grams
How do I determine the mass of Mn present?We'll begin by obtaining the number of mole of Mn. This can be obtained as follow:
From Avogadro's hypothesis,
6.02×10²³ atoms = 1 mole of Mn
Thus,
1.07×10²⁴ atoms = (1.07×10²⁴ atoms × 1 mole) / 6.02×10²³ atoms
1.07×10²⁴ atoms = 1.777 moles of Mn
Now, we shall determine the mass (in grams) of Mn. Details below:
Number of mole of Mn = 1.777 moles Molar mass of Mn = 55 g/mol Mass of Mn =?Mole = mass / molar mass
Cross multiply
Mass = Mole × molar mass
Mass of Mn = 1.777 × 55
Mass of Mn = 97.735 grams
Thus, from the above calculation, it is evident that the mass of Mn is 97.735 grams
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How many moles of anions are in 34.8 g of AlF3 A l F 3 ?
There are 0.610 moles of anion which are present in 34.8 g of aluminium trifluoride compound or AlF₃.
What is a mole?Mole is defined as the unit of amount of substance . It is the quantity which measures amount of substance of how many elementary particles are present in a that given substance.
It is defined as exactly 6.022×10²³ elementary entities. The elementary entity can be a molecule, atom ion depending on which type of substance is present. Amount of elementary entities which are present in a mole is called as Avogadro's number.
Number of moles of anion =mass/molar mass= 34.8/57= 0.610
Thus, there are 0.610 moles of anion present in 34.8 g of aluminium trifluoride or AlF₃.
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A phosphate-ion (PO43-) level in a water sample is 93.1 ppm (or mg/L). What is the concentration of this phosphate sample in molarity? Density of water is 1 g/mL Note: In the field of water quality, ppm and mg/L are the same unit.
Answer:
The molarity of a solution can be calculated by dividing the number of moles of solute by the volume of the solution in liters. To calculate the number of moles of solute in a solution, we first need to find the mass of the solute.
Since the concentration of the phosphate sample is given in mg/L (ppm), we can convert this to grams by multiplying by 0.001:
93.1 mg/L x 0.001 g/mg = 0.0931 g/L
Next, we can find the number of moles of solute by dividing the mass of solute by its molar mass:
0.0931 g ÷ (1 mol/94 g) = 0.000989 mol/L
Finally, we can find the molarity of the solution by dividing the number of moles of solute by the volume of the solution:
0.000989 mol ÷ (1 L) = 0.000989 M
In going from room temperature (25 C) to 20 C above room temperature, the rate of reaction triples. Calculate the activation energy for the reaction .
Answer: 67890iuhnm, m
Explanation:b ghjit6789 k k
think about the sugar and water as made up of tiny particles
Both sugar and water are made of molecules and atoms.
What is meant by atoms and molecules?A tiny or very small particle of a chemical element is known as an atom, which may or may not present independently. Molecules are defined as a groups of atoms has the bond fuse together which represents the smallest part of a compound. Two or more identical or different atoms are chemically bonded with each other.
The smallest particle of a material that has all of the physical and chemical properties of the material. Molecules are made up of only one or more than one atom. Sugar has a solid state of matter whereas water has a liquid state of matter. Sugar which is a solid has more hard particles as compared to water whereas a liquid has less compact particles.
So we can conclude that both are made of molecules and atoms.
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Commercial vinegar contains close to 5 g of acetic acid (ch_3cooh) per 100 ml (1 l = 1000 ml) of solution. What is the molarity of acetic acid in vinegar?.
If commercial vinegar contains around 5 g of acetic acid (ch 3cooh) per 100 ml (1 l = 1000 ml) in solution, its molarity is 0.83 M.
Molarity is the amount of solute in moles per litre of solution.
Acetic acid's mass is reported as 5.0 g, and the solution's volume is 100.0 mL.
We divide the grammes of acetic acid by the molar mass in order to convert them from grammes to moles.
Acetic acid's chemical formula is CH₃COOH. Molar mass of acetic acid is equal to 2(12.01), 4(1.01), 2(16), 24.02, 4.04, and 32 grammes per mol. Acetic acid has a molecular weight of 5.0/60.06, or 0.083 moles.
Transform mL to L.
1 L equals 1000 mL, as we are aware.
The solution's molarity is equal to 0.083moles per 0.1000L, or 0.83M, thus we divide by 1000 to convert from mL to L. 100/1000 = 0.1000 L
Therefore, 0.83 M of acetic acid is present in vinegar.
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Calculate the number of carbon atoms in a 140.0 g sample of glucose (C6H1206).
Be sure your answer has a unit symbol if necessary, and round it to 4 significant digits.
There are 2.81 × 10^24 moles number of carbon atoms in a 140.0 g sample of glucose (C6H1206).
What is molar mass ?The term molar mass of a substance is defined as the mass in grams of one mole of the compound. In a substance, the amount of entities present e.g., atoms, molecules, ions. A mole of any substance is 6.022×10²³ molecules.
To calculate, we need to know the number of moles present in 140 grams of carbon.
number of moles = mass/molar mass
molar mass of glucose is = 180 g/mol
Therefore, the number of moles will be ;
140/180 = 0.7778 mole
1 mole of glucose contains 6 moles of carbon;
Then, 0.7778 moles will contain = 4.667 moles
the number of atoms in 1 mole is 6.02 × 10^23 atoms
The number of atoms in 4.667 moles will be :
4.667 × 6.02 × 10^23
= 2.81 × 10^24 atoms
Thus, 2.81 × 10^24 moles number of carbon atoms in a 140.0 g sample of glucose (C6H1206).
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Question 11 of 20:
Select the best answer for the question.
11. A gray dog pulled a sled with a mass of 25 kilograms 100 meters. A brown dog
pulled a sled with the same mass across the same distance, but in half the time.
Which statement compares the two correctly?
O A. Both dogs used the same amount of work, and the brown dog used less power.
O B. Both dogs did the same amount of work, and the brown dog used more power.
O C. The brown dog did more work and used less power.
O D. The brown dog did less work, and both dogs used the same amount of power.
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Both dogs used the same amount of work, and the brown dog used less power.
What is the difference between work and power?Work and power are both concepts in physics that are related to the transfer of energy, but they are not the same thing. Work refers to the amount of energy transferred to or from an object as a result of a force acting on it over a certain distance, whereas power refers to the rate at which work is done.
In other words, work is a measure of the total energy transferred, while power is a measure of how quickly that energy is transferred. Mathematically, work is defined as the product of the force applied to an object and the distance over which that force is applied, while power is defined as the rate of doing work, or the amount of work done per unit time.
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Calculate the freezing point of 0.300 molal aqueous solution of magnesium chloride,
(MgCl₂). Assume that the MgCl₂ has ionized completely and the Kf= 1.853 °C / molal
Answer: answer of the question is given below
Explanation:
Answer:
0.556 °C.
Explanation:
The freezing point depression of a solution can be calculated using the equation:
ΔTf = Kf x molality
Where ΔTf is the change in freezing point, Kf is the molal freezing point depression constant, and molality is the concentration of solute in mol/kg.
For magnesium chloride, Kf = 1.853 °C/molal. The molality of the solution can be calculated as follows:
molality = moles of solute / mass of solvent (in kilograms)
= 0.300 mol / (0.300 mol x 1000 g/mol) = 0.300 g/1000 g = 0.0003 kg/kg = 0.300 mol/kg
Now, substituting the values into the equation:
ΔTf = Kf x molality
= 1.853 °C/molal x 0.300 mol/kg
= 0.556 °C
So the freezing point of the 0.300 molal aqueous solution of magnesium chloride will be lower than the freezing point of pure water by 0.556 °C.
ALLEN
If Earth is 1.50 × 10^(8 km from the sun , what is the distance in Gm?
The distance of the Earth from the sun in gigameters is 1.50 × 10⁻⁴ Gm
How to convert km to Gm?A unit conversion is the expression of the same property in a different unit of measurement. To convert kilometers to gigameters, you need to divide the number of kilometers by 10¹². Here's the formula: Gigameters = Kilometers / 10¹²
To convert the distance from kilometers to gigameters (Gm), divide the number of kilometers by 10¹².
So, 1.50 × 10⁸ km ÷ 10¹² = 1.50 × 10⁻⁴ Gm
Therefore, the distance from the Earth to the Sun is approximately 1.50 × 10⁻⁴ Gm.
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How many grams of copper (i) nitrate (cuno 3 ) are required to produce 44. 00 grams of aluminum nitrate (al (no 3 )3 )?.
To determine how many grams of copper (I) nitrate (CuNO3) are required to produce 44.00 grams of aluminum nitrate (Al(NO3)3), we need to use stoichiometry and the balanced chemical equation that relates the two compounds.
The balanced chemical equation for the reaction is: 3CuNO3 + 2Al -> 3Cu + 2Al(NO3)3 This equation tells us that 3 moles of CuNO3 react with 2 moles of Al to produce 2 moles of Al(NO3)3 and 3 moles of Cu.
We can use this information to calculate the amount of CuNO3 required to produce 44.00 grams of Al(NO3)3 as follows: Calculate the molar mass of Al(NO3)3: Al(NO3)3 = 1(26.98) + 3(14.01 + 3(16.00)) = 213.00 g/mol
Convert the given mass of Al(NO3)3 to moles: moles Al(NO3)3 = 44.00 g / 213.00 g/mol = 0.2065 mol Use the stoichiometric ratio from the balanced chemical equation to determine the moles of CuNO3 required: 3 moles CuNO3 / 2 moles Al(NO3)3 = x moles CuNO3 / 0.2065 moles Al(NO3)3 x moles CuNO3 = 3/2 x 0.2065 mol = 0.3097 mol
By using the balanced chemical equation, we can relate the amount of one compound to the amount of another compound in the reaction. This allows us to use stoichiometry to calculate the amount of one compound required to produce a given amount of another compound.
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What is the net ionic equation for the following reaction?
H2O2 + 2KI + 2HCl → 2H2O + I2 + 2KCl
H[tex]_2[/tex]O[tex]_2[/tex] + 2ICl [tex]\rightarrow[/tex] I[tex]_2[/tex] + 2OH⁻ is the net ionic equation for the given reaction. The net ionic equation is frequently employed in acid-base neutralization, double displacement, and redox processes.
What is net ionic equation?The net ionic equation is indeed a chemical equation for something like a reaction that only includes the species that are involved in the reaction. The net ionic equation is frequently employed in acid-base neutralization, double displacement, and redox processes.
In those other terms, the net ionic includes elements to water-based processes involving strong electrolytes.
H[tex]_2[/tex]O[tex]_2[/tex] + 2KI + 2HCl → 2H[tex]_2[/tex]O + I[tex]_2[/tex]+ 2KCl
H[tex]_2[/tex]O[tex]_2[/tex] + 2K⁺+2I⁻ + 2H⁺ + 2Cl⁻ → 2H⁺ + 2OH⁻ + I[tex]_2[/tex]+ 2K⁺ + 2Cl⁻
H[tex]_2[/tex]O[tex]_2[/tex] + 2ICl [tex]\rightarrow[/tex] I[tex]_2[/tex] + 2OH⁻
Therefore, H[tex]_2[/tex]O[tex]_2[/tex] + 2ICl [tex]\rightarrow[/tex] I[tex]_2[/tex] + 2OH⁻ is the net ionic equation for the given reaction.
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3. In chemistry, a structural isomer of a compound is another compound whose molecule has the same number of atoms of each element, but with logically distinct bonds between them. Consider an alkene compound. Draw all possible structural isomers for an alkene with a molecular formula C6H12.
[4 marks]
All the possible structural isomers for the molecular formula C₆H₁₂ are given here. All of them has the same number of carbon and hydrogen atoms but with different structures.
What are structural isomers ?Isomers are compounds with the same chemical formula but different structures, spatial conformation, geometry, functional groups etc. There are are different kinds of isomers.
Structural isomers are compounds with same formula but different structures. In the case alkanes, alkenes or alkynes, the position of the branches or groups attached can be of different but formula stay the the same.
Here, the compound with the formula, C₆H₁₂ have structures similar of alkenes and can have ring structures as shown in the image. The position of the double bond or the branches are different in each isomers.
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What property is dependent on the mass of the object?
A: temperature
B: phase
C: state
D: heat
Answer:
D Heat
Explanation:
Tell me if you need explain
ALLEN
Length: 2:00:00
ge 1:
2 3
5
I
Silas Calderon: Attempt 1
What do the domains Bacteria and Archaea have in common?
Prokaryotes, single-celled microorganisms without nuclei, include both bacteria and archaea.
Describe prokaryotes.
Prokaryotes are creatures without a nucleus or other organelles in their cells. Bacteria and archaea, two separate groupings of prokaryotes with allegedly independent evolutionary histories, are separated into. The majority of prokaryotes are tiny, single-celled creatures with a straightforward structure.
Both of them are microscopic, single-celled organisms with a wide range of forms. Bacteria and archaea both contain only one circular chromosome and no membrane-bound organelles. Archaea can contain flagella to help with movement, just like bacteria may.
Although there are many different shapes that bacteria and archaea can take, cocci, bacilli, and spirilli are the three that are most frequently found. In comparison to ordinary eukaryotes, bacteria and archaea are both typically tiny organisms.
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The chemical formula for cesium chloride is Cs Cl.
A chemist measured the amount of cesium chloride produced during an experiment. She finds that 30.8 g of cesium chloride is produced. Calculate the number
of moles of cesium chloride produced.
Round your answer to 3 significant digits.
The number of moles of cesium chloride produced 0.183 moles.
How to calculate number of moles?The number of moles of a substance can be calculated by dividing the mass of the substance by its molar mass.
According to this question, the chemical formula for cesium chloride is CsCl. A chemist measured the amount of cesium chloride produced during an experiment. She finds that 30.8 g of cesium chloride is produced.
The molar mass of Cesium chloride is 168.36 g/mol
Moles = 30.8g ÷ 168.36g/lol
moles = 0.183 moles
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What type of reaction would most likely occur when magnesium reacts with bromine?
you gonna get magnesium bromide MgBr2
Magnesium is metal and bromine is non-metal, and the combination of the two produces an ionic compound called magnesium bromide
Used as a catalyst.
Used for position-specific analysis of Triglycerols.
Widely used as an anticonvulsant for the treatment of neuropathy.
It is used as a mild sedative.
Which of the following is
the correct way to express
0.0000321 in scientific
notation?
A. 3.21 x 105
B. 32.1 x 106
C. 3.21 x 10-5
D. 32.1 x 10-6
If each household emits 60 metric tons of co2 on average and 21 metric tons are from transportation, how many are from the bus?.
If each household emits 60 metric tons of CO2 on average, and 21 metric tons are from transportation, the remaining CO2 emissions from a household would be 60 - 21 = 39 metric tons.
However, it is not possible to determine how many metric tons of CO2 are specifically from the use of buses, as this information is not specified. The 21 metric tons of CO2 emissions from transportation could come from a variety of sources, including buses, cars, trains, and airplanes. Without further information, it is not possible to determine exactly how many of the 21 metric tons of transportation-related CO2 emissions are specifically from the use of buses. To determine this information, you would need data that breaks down the total transportation-related CO2 emissions into smaller categories, such as emissions from individual modes of transportation. So, while it's known that each household emits an average of 60 metric tons of CO2 per year, with 21 of those metric tons being from transportation, it is not possible to determine the exact amount of CO2 emissions from the use of buses without additional information.
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a specie with initial concentration 1.4×10^-2 mol L-1 decay by first order kinetics with a rate constant 2.35×10^2L mol-1 s-1. what is the half-life if this specie?
Answer:
293 ms
Explanation:
The half-life of a first-order reaction can be calculated using the following formula:
t1/2 = 0.693 / k
Where t1/2 is the half-life and k is the rate constant.
For this reaction, the rate constant is 2.35 x 10^2 L/mol/s, so:
t1/2 = 0.693 / (2.35 x 10^2 L/mol/s) = 0.293 / (2.35 x 10^2) s = 0.000293 s = 293 ms
Answer:
0.293 / 2.35 × 10^2 seconds.
Explanation:
The half-life of a first order reaction can be calculated using the equation:
t1/2 = 0.693 / k
where t1/2 is the half-life, k is the rate constant, and 0.693 is the natural logarithm of 2.
Substituting the values given in the question:
t1/2 = 0.693 / 2.35 × 10^2 L mol-1 s-1 = 0.293 / 2.35 × 10^2 s
So, the half-life of the species is approximately 0.293 / 2.35 × 10^2 seconds.
Question 6 of 10
Which shows an isomer of the molecule below?
O A.
OB.
O C.
O D.
The molecule D shows an isomer of the molecule given below. Therefore, option D is correct.
What is an isomer ?The term Isomer is defined as the compounds that contain exactly the same number of atoms, i.e., they have exactly the same empirical formula, but differ from each other by the way in which the atoms are arranged.
Isomerism is the phenomenon in which more than one compounds have the same chemical formula, but they have different chemical structures.
Therefore, given molecule and D molecule are isomers of each other because they have the same number of atoms, but they differ in arrangement of the atoms.
Thus, option D is correct.
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In the laboratory, a student adds 14.0 g of manganese(II) nitrate to a 250. mL volumetric flask and adds water to the mark on the neck of the flask. Calculate the concentration (in mol/L) of manganese(II) nitrate, the manganese(II) ion and the nitrate ion in the solution.
[Mn(NO3)2] = ?M
[Mn2+] = ?M
[NO3-] = ?M
The number of moles of 14 g of manganese nitrate is 0.078 moles. Then molarity of the solution is 0.312 M. The molarity of Mn²⁺ in the solution is 0.312 M and the molarity [NO₃⁻] is 0.624 M.
What is molarity ?Molarity of a solution is the ratio of number of moles of the solute to the volume of solution in liters. It is the common term for representing the concentration of a solution.
Molar mass of manganese nitrate = 178.9 g/mol
no.of moles in 14 g = 14/178.9 = 0.078 moles.
then molarity of [Mn (NO₃)₂] = 0.078/0.25 L = 0.312 M.
In one mole of the solution there is one mole of Mn²⁺.
then [Mn²⁺ ] = [Mn (NO₃)₂] = 0.312 M.
One mole of the compound contains 2 moles of the nitrate ions. Hence,
[NO₃⁻] = 2 × 0.312 = 0.626 M.
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Using tabulated ∆° values in the text, determine the enthalpy change (in kJ) that occurs during the formation of water from its elements.
32 ()+2 ()→22(l) ∆=?
The enthalpy of formation of H₂ and O₂ are zero. Then , the enthalpy of formation of water is 285 kJ.
What is enthalpy of formation ?Enthalpy change of a chemical reaction of physical change is the change in heat energy absorbed or evolved during the change or reaction. It is represented as ΔHf⁰.
The enthalpy of formation of elements in molecular state is zero. Hence the enthalpy of formation of H₂ and O₂ are zero.
The enthalpy of formation of water = -285 kJ.
enthalpy of reaction = enthalpy of products - enthalpy of reactants.
ΔHr = -285 kJ - 0+0 = - 285 kJ.
Therefore, the enthalpy change during the formation of water from its elements is - 285 kJ.
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Your complete question is as follows:
Using tabulated ∆Hf° values in the text, determine the enthalpy change (in kJ) that occurs during the formation of water from its elements:
2 H2 (g) + O2 (g) → 2 H2O (l) ∆H = ?
Colorimetric Analysis of Asprin Chem Lab:
Students prepared a solution by hydrolyzing 0.3219 g of a crushed aspirin tablet in NaOH and then diluting with DI water in a 100-mL volumetric flask. Next, they transferred 1.50 mL of the solution to a 50-mL volumetric flask and diluted to the mark with FeCl3-KCl-HCl solution. The absorbance of the dilution was 0.346. Using their standard curve, they determined the concentration to be 5.02 × 10e-4 mol/L. If an aspirin tablet weighs 0.4267 g, determine the mass of ASA (in mg) per tablet.
*Note the answer is 400 mg and the Molarity of the standard solution is unknown.
-To account for not using the whole crushed tablet multiply by the ratio of m(tablet)/m(tablet used).
-I'm not sure which step in the calculations to apply this ratio.
-Any help would be greatly appreciated!
The mass of ASA - Acetylsalicylic acid per tablet is 214.9 mg. The number of moles present in the tablet, is 0.001190.
For this experiment it is important to find the number of moles of ASA present in the solution. By doing this we will get the amount of ASA in the tablet also.
Students prepared a solution by hydrolyzing 0.3219 g of a crushed aspirin tablet in NaOH and then diluting with DI water in a 100-mL volumetric flask.
Number of moles = mass of ASA / molar mass of ASA
The molar mass of ASA = 180.16 g/mol
Therefore, Number of moles = 0.3219 g / 180.16 g/mol
= 0.001785 mol.
Now finding the number of moles present in the tablet,
Moles in tablet = (moles of ASA from solution) x (mass of tablet / mass of solution)
= 0.001785 mol x (0.4267 g / 0.3219 g x 1.50 mL / 50 mL)
= 0.001190 mol
Now finding the mass of ASA,
Mass of ASA per tablet = (moles of ASA in tablet) x (molar mass of ASA)
= 0.001190 mol x 180.16 g/mol
= 0.2149 g or 214.9 mg
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what is spaced practice what is spaced practice
Spaced practice is a learning strategy where the time between learning sessions is increased over time.
How is spaced practice applied?In this approach, material is studied multiple times, with increasing intervals between each session. This type of practice is thought to enhance long-term retention and improve memory compared to massed practice, where all the material is studied in one single session.
Spaced practice is often used in education and training programs, especially for subjects that require memorization or recall of information. The idea behind spaced practice is that it allows time for the material to be consolidated in memory, rather than simply being repeated in short-term memory.
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Estimate the number of photon emitted in one second from a LED lamp of 50 watts, if the band-gap energy of the LED is 2.0 eV and with 90% energy conversion from electricity to light energy
Number of photons emitted = 2167200 photons/second
What are photons emitted?Photons are particles of light that are emitted from atoms. They exist in a wide range of energies and wavelengths and can be emitted from both natural and artificial sources.
Photons are emitted when an electron in an atom moves from a higher energy state to a lower energy state.
1. Number of photons emitted = (Energy conversion efficiency) × (Power in Watts) × (eV/J) × (Avogadro's number) × (1/Energy of band gap)
Number of photons emitted = (0.9) × (50) × (1.6 x 10-19/1) × (6.02 x 1023) × (1/2.0)
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Consider how sodium chloride and butane interact with water: ______is more Iikely to dissolve In water because it is_____and is attracted to the______of water:
Sodium chloride is more likely to dissolve in water because it is polar and is attracted to the polar molecules of water. On the other hand, butane is nonpolar and is not attracted to the polar molecules of water, so it is less likely to dissolve.
Sodium chloride, also known as table salt, has ionic bonds, meaning it is composed of positive and negative ions. The positive sodium ion and negative chloride ion are attracted to the polar water molecules, which have a positive charge at one end and a negative charge at the other. This attraction between the ions of salt and the polar water molecules leads to the dissolution of salt in water.
Butane, on the other hand, is a nonpolar substance. It is composed of nonpolar carbon and hydrogen atoms arranged in a linear structure. These nonpolar atoms are not attracted to the polar water molecules, so they do not dissolve well in water. In fact, butane is a hydrocarbon and is one of the components of natural gas. It is a fuel that is used for heating and cooking, and it is not soluble in water.
In conclusion, the solubility of a substance in water depends on its molecular structure and the type of bonds it contains. Polar substances tend to dissolve well in water because they are attracted to the polar water molecules, while nonpolar substances are less likely to dissolve because they are not attracted to the polar water molecules.
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