The enthalpy change of the reaction is 52.6604 kJ/mol.
What is Enthalpy?
Enthalpy is a thermodynamic property that describes the amount of heat released or absorbed by a system at constant pressure. It is represented by the symbol H and is measured in units of joules (J) or kilojoules (kJ).
To find the enthalpy change of the reaction (ΔH), we can use the formula:
ΔH = q / n
where q is the heat absorbed or released by the reaction, and n is the number of moles of Ca that reacted.
First, we need to calculate the heat absorbed by the solution. We can use the formula:
q = m × c × ΔT
where m is the mass of the solution (in grams), c is the specific heat capacity of the solution (in J/g°C), and ΔT is the change in temperature (in °C).
We can calculate the mass of the solution using its density:
mass = volume × density
mass = 200.0 mL × 1.00 g/mL
mass = 200.0 g
The change in temperature is:
ΔT = 29.2 °C - 26.2 °C
ΔT = 3.0 °C
Now we can calculate q:
q = 200.0 g × 4.184 J/g°C × 3.0 °C
q = 2510.4 J
Next, we need to calculate the number of moles of Ca that reacted. We can use the mass of Ca and its molar mass:
n = m / M
The molar mass of Ca is 40.08 g/mol.
n = 1.911 g / 40.08 g/mol
n = 0.0476 mol
Finally, we can calculate the enthalpy change of the reaction:
ΔH = q / n
ΔH = 2510.4 J / 0.0476 mol
ΔH = 52660.4 J/mol
Converting to kJ/mol:
ΔH = 52.6604 kJ/mol
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the reaction of -COOH and -NH₂:
a) forms urea
b) creates a peptide bond
c) forms glycogen
d) forms a ketone body
The reaction of -COOH and -NH₂ creates a peptide bond.
What is peptide bond?Peptide bond is defined as a type of amide type covalent chemical bond which is formed between the two simultaneous molecules of amino acid in such a way that carboxyl group of one molecule of amino acid get attached to the NH₂ group of another molecules of Amino acid.
Formation of Peptide bondPeptide bond is formed by the elimination of water molecules.
The hydroxyl group from the carboxyl and proton hydrogen cation from NH₂ group.
Thus, we concluded that the reaction of -COOH and -NH₂ creates a peptide bond by losing—OH from the -COOH and H+ from the -NH₂.
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4. Long answer type questions: a. b. C. d. e. f. g. h. j. i. What are the constituent gases of air? Why is the surrounding air not seen with the eyes? How do you prove that air supports burning? How do you show that air occupies space? How do you prove that air has weight? How is air useful to us? Mention any three points. Write any three properties of air. How can you say that air exerts force? Write any four effects of air pollution. Write any three causes of air pollution and any two control measures of it.
1. The constituent gases of air are:
Nitrogen Oxygen Argon Carbon Dioxide2. The surrounding air is not seen with the eyes because it is transparent. Air molecules are not visible to the na-ked eye, and they do not scatter or absorb visible light significantly. Therefore, air appears colorless and transparent.
What is air?3. To prove that air supports burning, you can perform an experiment with a burning candle. Place a glass jar or bell jar over a lit candle, ensuring that the jar is airtight. As the candle burns, it consumes oxygen from the air inside the jar. Eventually, the candle flame will go out due to the lack of oxygen, proving that air (specifically oxygen) is necessary for burning.
4. To show that air occupies space, you can perform a simple experiment using a plastic bottle or syringe. Fill the bottle or syringe with water, ensuring there are no air bubbles. Then, cover the opening tightly and try to compress the air inside. You will find that it is not possible to compress the air significantly, indicating that air occupies space.
5. To prove that air has weight, you can use a sensitive balance or scale. Weigh an airtight container or balloon, and then fill it with air. The weight of the container or balloon with the added air will be greater than its initial weight, demonstrating that air has weight.
6. Air is useful to us in various ways. Three points highlighting the importance of air are:
Breathing and RespirationCombustion and Energy ProductionClimate Regulation7. Three properties of air include:
Air is Compressible: Air can be compressed or expanded under different conditions, allowing it to fill various spaces and containers.Air has Mass: Air molecules have mass, which means air itself has weight. It exerts pressure on objects and surfaces.Air Exerts Pressure: Due to the collisions of air molecules with surfaces, air exerts pressure in all directions. This pressure is known as atmospheric pressure.Air exerts force in various ways. For example, air pressure allows objects like airplanes to fly by providing lift. Air resistance or drag opposes the motion of objects moving through the air, creating a force that can affect their speed and trajectory.
8. Four effects of air pollution include:
Respiratory ProblemsEnvironmental Damage:Climate ChangeHuman Health Impacts9. Causes of pollution:
Industrial EmissionsVehicle EmissionsResidential and Agricultural Activities10. Two control measures for air pollution include:
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The "Ring of Responsibility" requires a next to water bodies. O 50-foot 43 3-foot O 5-foot O 15- to 25-foot untreated buffer zone
The "Ring of Responsibility" requires a 15- to 25-foot untreated buffer zone next to water bodies.
What is buffer zone?A buffer zone is an area of land that separates two or more countries, states, or territories, and is often demilitarized. The purpose of a buffer zone is to provide a space for negotiations and to reduce the possibility of conflict and war. Buffer zones can also be used to protect sensitive natural resources or habitats, such as areas of wilderness or wildlife. Buffer zones can be permanent or temporary, and can range in size from a few miles to hundreds of miles. In addition to physical barriers, buffer zones can also include economic, political, and social measures to reduce tensions between two or more parties. Buffer zones are an important tool in international relations, as they can help to prevent armed conflict and promote peaceful resolution of disputes.
This buffer zone is intended to prevent pollutants from entering the water body and protect it from potential environmental damage.
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State what you would expect to happen to the cell potential when the following changes are made to the corresponding cells. Confirm your prediction by using the Nernst equation in each case.
(a) The pressure of hydrogen in the left-hand compartment is increased.
(b) The concentration of HCl is increased.
(c) Acid is added to both compartments.
(d) Acid is added to the right-hand compartment.
(e) The molar concentration of silver nitrate in the left-hand compartment is increased.
(f) The pH of the right-hand compartment is decreased.
871g of sodium chloride is how many moles
Answer:
14.9 mol
Explanation:
To find the number of moles in a given mass of a sample of sodium chloride (NaCl), we can multiply the number of grams in the sample by the molar mass of sodium chloride, which is 58.44 g/mol.
871 g × (1 mol / 58.44 g)
= 871/58.44 mol
≈ 14.9 mol
Note that we rounded to 3 significant figures in the final answer because that is how many significant figures were given in the mass measurement of the sodium chloride sample.
a liter of over the counter cough syrup contains a total of 15.0g of codeine. How many moles of codeine is that is given AW of C=12.0 amu, Aw of H = 1.0 amu, AW oN = 14.0 amu amd AW OF O = 16.0 amu
The number of mole in the 15.0 grams of codeine, C₁₈H₂₁NO₃ is 0.05 mole
How do I determine the number of mole?We know that the mole of a substance is related to it's mass and molar mass according to the following formula:
Mole = mass / molar mass
Therefore, with the above formula, we can determine the number of mole. Details below
Mass of codeine, C₁₈H₂₁NO₃ = 15.0 grams Molar mass of codeine, C₁₈H₂₁NO₃ = (12×18) + (1×21) + 14 + (16×3) = 216 + 21 + 14 + 48 = 299 g/mol Number of mole of codeine, C₁₈H₂₁NO₃ =?Mole = mass / molar mass
Number of mole of codeine, C₁₈H₂₁NO₃ = 15/ 299
Number of mole of codeine, C₁₈H₂₁NO₃ = 0.05 mole
Thus, the number of mole is 0.05 mole
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1.write the balanced equation for
CuCl2+HNO3+AgNO3=
What is the general molecular formula for phenol?
1
1
The general molecular formula for phenol is C6H5OH. It is an aromatic organic compound with a hydroxyl group bonded to a carbon atom of a cyclic structure. The ring structure has alternate double and single bonds. The formula of phenol is C6H5OH. Benzene has the formula C6H6. It is a hexagonal ring of six carbon atoms bonded with alternate single and double bonds. Each carbon atom in benzene has a bond with a hydrogen atom. In phenol, a hydroxyl group replaces one of the hydrogen atoms.
The reaction of CuCl2, HNO3, and AgNO3 is a redox reaction. In a redox reaction, one substance loses electrons and is oxidized, while another substance gains electrons and is reduced. In this reaction, CuCl2 is oxidized to Cu2+, HNO3 is reduced to NO, and AgNO3 is reduced to Ag.
The balanced equation for the reaction is:
CuCl2 + 2HNO3 + 2AgNO3 → Cu2+ + 2NO + 2AgCl
The products of the reaction are copper(II) ions, nitrogen monoxide gas, and silver chloride precipitate.
Here are some of the properties of phenol:
Phenol is a white crystalline solid that is soluble in water.
Phenol has a strong, characteristic odor.
Phenol is a mild acid.
Phenol is toxic and can cause burns to the skin and eyes.
Phenol is used in a variety of products, including disinfectants, antiseptics, and plastics.
convert 5 liters into kiloliters
Answer:0.005
Explanation:kilo means 1000 do you divide 5 by 1000 and you get.005
Answer: 0.005 kilolitres
Explanation:
5 liters = 0.005 kilolitres
Why? Because liters - kilolitres: ÷ 1000
SHOWING ALL WORK... Calculate the percent composition of nitrogen in Methyl Orange (C14H14N3NaO3S)
answer and explanation
to determine the percentage by mass of N on methyl orange.
We must first calculate the molar mass of methyl orange:
Carbo: 14 x 12.0 = 168
Hydrogen: 14 x 1.00 = 14
Sodium: 1 x 22.0 = 22.0
Nitrogen: 3 x 14.00 = 42
Oxygen: 3 x 15.99 = 47.97
Sulphur: 1 x 32.0 = 32.0
Total Methyl orange molar mass = 327,33 g/mol
Percentage mass of Nitrogen = mass of nitrogen/ mass of methyl orange x 100
42/327.33 x100
= 12.8%
A solid powder is composed of molecules containing silver (Ag), nitrogen (N), and oxygen (O) atoms. All of the molecules are identical. How is this substance classified? (A) as a heterogeneous mixture (B) as a homogeneous mixture (C) as a compound (D)as an element
Answer: I had this answer on my test and got it correct. The answer is C
Explanation: the explanation is above
Calculate the number of moles in 11.0 grams of NaOH . Please show your work to receive credit.
Answer: 0.275 moles
Explanation: Na- 22.99g (on periodic table)
O- 16g and H- 1.01
22.99 + 16 + 1.01 = 40g/mol of NaOH
11g of NaOH / 40g / mol of NaOH = 0.275mol NaOH
7) How many molecules of CO2 are in 2.5 L at STP?
By using the ideal gas law and Avogadro's number, we find that there are approximately 6.72 × 10^22 molecules of CO2 in 2.5 L at STP.
To determine the number of molecules of CO2 in 2.5 L at STP (Standard Temperature and Pressure), we can use the ideal gas law and Avogadro's number.
Avogadro's number (N_A) is a fundamental constant representing the number of particles (atoms, molecules, ions) in one mole of substance. Its value is approximately 6.022 × 10^23 particles/mol.
STP conditions are defined as a temperature of 273.15 K (0 °C) and a pressure of 1 atmosphere (1 atm).
First, we need to convert the volume from liters to moles of CO2. To do this, we use the ideal gas law equation:
PV = nRT,
where P is the pressure, V is the volume, n is the number of moles, R is the ideal gas constant, and T is the temperature in Kelvin.
Since we have STP conditions, we can substitute the values:
(1 atm) × (2.5 L) = n × (0.0821 L·atm/(mol·K)) × (273.15 K).
Simplifying the equation:
2.5 = n × 22.4149.
Solving for n (the number of moles):
n = 2.5 / 22.4149 ≈ 0.1116 moles.
Next, we can calculate the number of molecules using Avogadro's number:
Number of molecules = n × N_A.
Number of molecules = 0.1116 moles × (6.022 × 10^23 particles/mol).
Number of molecules ≈ 6.72 × 10^22 molecules.
Therefore, there are approximately 6.72 × 10^22 molecules of CO2 in 2.5 L at STP.
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How many grams of NaCl
You would recover 36.525g of NaCl after evaporating all of the water.
How to find the how many grams of NaCl that would be recover when all water is evaporated off of this solution?To find the grams of NaCl that would be recovered after evaporating all the water, we can use the following formula:
mass = moles * molar mass
Where:
Moles = Molarity * Volume
Molarity = 0.250 M
Volume = 2500.0 mL = 2.5 L
Molar mass of NaCl = 58.44 g/mol
mass = 0.250 M * 2.5 L * 58.44 g/mol
mass = 36.525 g
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In a closed system, If a gas is transported to a container with double the volume of the previous container, the gas was held in, what is the gases' new volume?
The volume of the gas is fixed and will not change.
The volume of the gas will be half the original volume.
The volume of the gas will be the original volume squared.
The volume of the gas will be double the original volume.
Answer:
The volume of the gas is fixed and will not change.
Explanation:
The volume of the gas will not change because there is no change in temperature. Temperature increases the volume of gases enclosed in a container.
The Sun has been shining on this swimming pool all day. The water is much warmer than it was in the morning. Describe what is happening to the water in terms of temperature, particle speed, and kinetic energy.
Answer:
The waters' temp increased
Explanation:
The temperature of the water in the swimming pool has increased due to the heat from the Sun. As a result, the particles in the water are moving faster and have a higher kinetic energy than in the morning.
An instantaneous dipole occurs when a molecule's moving electrons are briefly more concentrated in one place than another, causing the molecule to become temporarily polarized.
True
False
An instantaneous dipole occurs when a molecule's moving electrons are briefly more concentrated in one place than another, causing the molecule to become temporarily polarized.
The correct option is True.
What are dipoles?Dipoles refer to a separation of charges where one end of a substance has a positive charge while the other end has a negative charge.
In chemical compounds, dipoles occur within a molecule that has covalently bonded atoms or atoms that share electrons in the covalent bond.
The dipole may be permanent dipoles or temporary dipoles.
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Which of the following is an incorrect representation for a neutral atom?
36Li
613C
3063Cu
1530P
This representation suggests that the element is phosphorus (P) with a mass number of 30, which is incorrect. The correct mass number for phosphorus is approximately 30.97. The incorrect representation for a neutral atom is 36Li
To determine the correct representation for a neutral atom, we need to consider the atomic number (Z) and mass number (A) of the element. The atomic number represents the number of protons in the nucleus, while the mass number represents the sum of protons and neutrons.
Let's analyze the given representations:
36Li:
This representation suggests that the element is lithium (Li) with a mass number of 36, which is incorrect. The correct mass number for lithium is approximately 6.94.
613C:
This representation suggests that the element is carbon (C) with a mass number of 13, which is correct. Carbon has different isotopes, and 13C represents one of its stable isotopes.
3063Cu:
This representation suggests that the element is copper (Cu) with a mass number of 63, which is correct. Copper has different isotopes, and 63Cu represents one of its stable isotopes.
1530P:
This representation suggests that the element is phosphorus (P) with a mass number of 30, which is incorrect. The correct mass number for phosphorus is approximately 30.97.
Therefore, the incorrect representation for a neutral atom is 36Li, as it does not match the known properties of lithium.
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Vinegar is sold at the grocery store with a concentration of 5.0 % acetic acid. How many grams of acetic acid are in 28 g of Vinegar?
White vinegar typically consists of 93%–96% water and 4–7% acetic acid. It can be used to cooking, bake, cleaning, and get rid of weeds. It can also help you lose weight and lower your blood sugar and cholesterol. Consumption is safe in moderation, but excessive consumption or when combined with certain medications could be harmful.
Apple cider vinegar is widely used in cooking and as a salad dressing because it contains acetic acid and nutrients like vitamins C and B vitamins. But at the same time, it's been utilized customarily as medication. It helps in losing weight.
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How many molecules are in 7.62 L of CH4, at 87.5°C and 722 torr
Answer: There are \(1.469 \times 10^{23}\) molecules present in 7.62 L of \(CH_4\) at \(87.5^{o}C\) and 722 torr.
Explanation:
Given : Volume = 7.62 L
Temperature = \(87.5^{o}C = (87.5 + 273) K = 360.5 K\)
Pressure = 722 torr
1 torr = 0.00131579
Converting torr into atm as follows.
\(722 torr = 722 torr \times \frac{0.00131579 atm}{1 torr}\\= 0.95 atm\)
Therefore, using the ideal gas equation the number of moles are calculated as follows.
PV = nRT
where,
P = pressure
V = volume
n = number of moles
R = gas constant = 0.0821 L atm/mol K
T = temperature
Substitute the values into above formula as follows.
\(PV = nRT\\0.95 atm \times 7.62 L = n \times 0.0821 L atm/mol K \times 360.5 K\\n = \frac{0.95 atm \times 7.62 L}{0.0821 L atm/mol K \times 360.5 K}\\= \frac{7.239}{29.59705}\\= 0.244 mol\)
According to the mole concept, 1 mole of every substance contains \(6.022 \times 10^{23}\) atoms. Hence, number of atoms or molecules present in 0.244 mol are calculated as follows.
\(0.244 mol \times 6.022 \times 10^{23}\\= 1.469 \times 10^{23}\)
Thus, we can conclude that there are \(1.469 \times 10^{23}\) molecules present in 7.62 L of \(CH_4\) at \(87.5^{o}C\) and 722 torr.
A spoonful of table salt dissolve in a bowl of soup is what change?
Answer:
Dissolving a solid in liquid, such as table salt in water, is a physical change because only the state of the matter has changed.
Explanation:
When a spoonful of table salt (sodium chloride, NaCl) dissolves in a bowl of soup, a physical change occurs because, the chemical composition of the salt (sodium chloride) remains the same; it's just dispersed in the liquid. This change is known as dissolution or dissolving.
Here's what happens;
Physical Mixing: When you add the salt to the soup, the salt crystals mix with the liquid soup. The salt particles spread out and become evenly distributed throughout the soup.
Solute and Solvent: In this process, the salt is the solute, and the soup is the solvent. The solute is the substance being dissolved (salt), and the solvent is the substance that does the dissolving (soup).
Ion Formation: As the salt crystals dissolve, the sodium (Na+) and chloride (Cl-) ions that make up the salt separate from each other. The water molecules in the soup surround and interact with these ions, helping to pull them apart from the crystal structure.
Ionic Interaction: The charged ions from the salt interact with the polar molecules in the soup, particularly the water molecules. This interaction forms a solution, where the salt ions are evenly dispersed throughout the liquid.
Homogeneity: The resulting mixture appears uniform and homogeneous. You can't easily distinguish the salt from the soup, and the taste of the soup becomes salty due to the presence of dissolved salt ions.
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1)
If I have 45 liters of helium in a balloon at 25°C and increase the
temperature of the balloon to 55° C, what will the new volume of the
balloon be?
Answer:
52.8 Liters
Explanation:
Gay-Lussacs law states that P1/T1 = P2/T2
if:
P1 = 45T1 (in Kelvins) = 25 + 273.1 =298.1P2= ?T2 = 55 + 273.1 = 328.1then:
45/298.1 = P2/328.1
P2 = 52.8
The new volume of the balloon is 52.8 Liters this can be calculated by using gas laws.
Charles law:Charles law states the volume occupied by a fixed amount of gas is directly proportional to its absolute temperature. It is given by
V₁/T₁ = V₂/T₂
What information do we have?
V₁ = 45 L
T₁ = 25 + 273.1 =298.1 K
T₂ = 55 + 273.1 = 328.1 K
To find:
V₂= ?
On substituting the values:
45/298.1 = V₂/328.1
V₂ = 52.8 L
Thus, the volume of the balloon is 52.8 liters.
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Please help, its due today! I'll also make you brainiest (put them in an order that's simple, look at the picture and you'll see what I mean) Thank you and God bless! <33
On beaches there are often areas of grassy dunes where people are prohibited from walking. How do these protected areas preserve ecosystem services? Use the graphic organizer to categorize the following as either examples of land reclamation of protecting biodiversity.
Answer:
Preventing erosion – Land Reclamation
Protecting nesting areas – Protecting Biodiversity
Preventing littering – Land Reclamation
Preventing habitat disruption – Protecting Biodiversity
Protecting native species – Protecting Biodiversity
Preventing contamination of soil – Land Reclamation
Explanation:
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How is this compound classified C4H6O4
The compound C4H6O4 can be classified as a dicarboxylic acid. In this case, the presence of four carbon atoms (C4) indicates that it is a relatively larger molecule.
The molecular formula also contains six hydrogen atoms (H6) and four oxygen atoms (O4). The presence of oxygen and carbon atoms suggests the possibility of carboxyl groups (-COOH) in the compound. Carboxyl groups are functional groups consisting of a carbonyl group (C=O) and a hydroxyl group (-OH) attached to the same carbon atom.
Since the compound contains four oxygen atoms, it is possible that it contains two carboxyl groups. A compound with two carboxyl groups is classified as a dicarboxylic acid. Dicarboxylic acids are organic compounds that have two carboxyl functional groups.
They are characterized by their ability to donate two protons (H+) and act as acids. Therefore, based on the molecular formula C4H6O4, the compound is classified as a dicarboxylic acid.
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A sea turtle is 3feet below the surface of the sea ??? Help me ple
Identifying Short-Term Changes
Egrets are birds that walk into the shallow waters of
marshes and wetlands to catch fish and insects with
their long beaks.
Which short-term environmental change is most likely
to directly affect a population of egrets along the coast
of Florida?
Odrought
O earthquake
O forest fire
Answer:
drought
Explanation:
on edge 2021
Answer:
drought
Explanation
its right on edge
A gas has a volume of 50.0 mL at a temperature of 10.0 K and a pressure of 760. kPa. What will be the new volume when the temperature is changed to 20.0 K and the pressure is changed to 380. kPa?
To solve this problem using the gas laws, we need to use the Ideal Gas Law. This law states that the product of the pressure and the volume of a gas is proportional to the absolute temperature.
The equation of the Ideal Gas Law is the following:
\(\boxed{\large\displaystyle\text{$\begin{gathered}\sf \bf{\dfrac{P_1V_1}{T_1}=\frac{P_2V_2}{T_2} } \end{gathered}$} }\)
Where:
P₁ = initial pressure = 760 kPaV₁ = initial volume = 50.0 mL = 0.050 LT₁ = initial temperature = 10.0 KP₂ = Final pressure = 380 kPaT₂ = final temperature = 20.0 KV₂ = Final volume = ?We clear for V₂:
\(\boxed{\large\displaystyle\text{$\begin{gathered}\sf \bf{V_2=\frac{P_1V_1T_2}{P_2T_1 } } \end{gathered}$} }\)
Where:
P₁ = initial pressure V₁ = initial volumeT₁ = initial temperatureP₂ = Final pressureT₂ = final temperatureV₂ = Final volumeSubstituting the known values:
\(\boxed{\large\displaystyle\text{$\begin{gathered}\sf \bf{V_2=\frac{760\not{kPa}\times0.050 \ L\times20.0\not{k} }{ 380\not{kPa}\times10.0\not{k} } } \end{gathered}$} }\)
\(\boxed{\large\displaystyle\text{$\begin{gathered}\sf \bf{V_2=\frac{760 \ L}{3800 } } \end{gathered}$} }\)
\(\boxed{\boxed{\large\displaystyle\text{$\begin{gathered}\sf \bf{V_2\approx0.2 \ Liters} \end{gathered}$} }}\)
When the temperature changes to 20.0 K and the pressure changes to 380 kPa, the new volume will be approximately 0.2 L (200.0 mL).What is the area civilization began?
Answer: Mesopotamia
Civilizations first appeared in Mesopotamia (what is now Iraq) and later in Egypt. Civilizations thrived in the Indus Valley by about 2500 B.C.E., in China by about 1500 B.C.E., and in Central America (what is now Mexico) by about 1200 B.C.E. Civilizations ultimately developed on every continent except Antarctica.
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Diazomethane has the following composition by mass: 28.57% C, 4.80% H, and 66.64% N. The molar mass of diazomethane is 42.04 g/mol. Find the molecular formula of diazomethane.
Answer:
CH2N2
Explanation:
To find the molecular formula, we must first find the empirical formula as follows:
28.57% C - 28.57g of Carbon
4.80% H - 4.80g of Hydrogen
66.64% N - 66.64g of Nitrogen
Next, we convert this mass values to mole by dividing by their respective atomic mass.
C = 28.57/12 = 2.38mol
H = 4.80/1 = 4.80mol
N = 66.64/14 = 4.76mol
Next, we divide each mole value by the smallest mole value (2.38mol)
C = 2.38mol ÷ 2.38 = 1
H = 4.80mol ÷ 2.38 = 2.01
N = 4.76mol ÷ 2.38 = 2
The empirical ratio of C, H and N is therefore 1:2:2. Hence, the empirical formula is CH2N2
To calculate the molecular formula;
(CH2N2)n = 42.04 g/mol
{12 + 1(2) + 14(2)}n = 42.04
{12 + 2 + 28}n = 42.04
{42}n = 42.04
n = 42.04/42
n = 1.00009
Since n = 1, molecular formula is CH2N2
A metal sample weighs 57.3g and has volume of 6.3mL what is the density of the sample
Answer:
9.10 g/mLExplanation:
The density of a substance can be found by using the formula
\(density = \frac{mass}{volume} \\\)
From the question we have
\(density = \frac{57.3}{6.3} \\ = 9.095238...\)
We have the final answer as
9.10 g/mLHope this helps you
Consider the following reaction:
2NO(g)+O2(g)→2NO2(g)
Estimate ΔG∘ for this reaction at each of the following temperatures and predict whether or not the reaction will be spontaneous. (Assume that ΔH∘ and ΔS∘ do not change too much within the give temperature range.) I need to find the temperature are 298K and 702K. For 298K It is simple because at standard temperature
ΔG∘ = DG(products)- DG(reactants).
Answer:
A. \(\mathbf{\Delta G^0 = -72.6 \ kJ/mol}\) ; as such the reaction is said to be spontaneous since the value of \(\mathbf{\Delta G^0 }\) is negative.
B. \(\mathbf{\Delta G^0_{702 \ K} = -13.29 \ kJ/mol.K}}\) and the reaction is spontaneous
Explanation:
The equation for this chemical reaction is :
\(2NO_{(g)} +O_{2(g)} \to 2NO_{2(g)}\)
Using the following relation to calculate \(\Delta G^0\);
\(\Delta G^0 = [2(\Delta G^0_{NO_{2(g)}}] - [1(\Delta G^0_{O_{2(g)}})+ 2(\Delta G^0_{NO_{g}})]\)
At 298 K; the standard Gibbs Free Energy for the formation are as follows:
\(\Delta G^0_{NO_{2(g)}} = 51.2 \ kJ/mol\)
\(\Delta G^0_{O_{2(g)}} = 0\)
\(\Delta G^0_{NO_{g}}= 87.6 \ kJ/mol\)
Replacing them into the above equation;
\(\Delta G^0 = [2(51.2 \ kJ/mol}] - [1(0)+ 2(87.6 \ kJ/mol})]\)
\(\Delta G^0 = [102.4 \ kJ/mol}] - [175.2 \ kJ/mol})]\)
\(\mathbf{\Delta G^0 = -72.6 \ kJ/mol}\)
Thus; \(\mathbf{\Delta G^0 = -72.6 \ kJ/mol}\) ; as such the reaction is said to be spontaneous since the value of \(\mathbf{\Delta G^0 }\) is negative.
B.
Using the same above chemical equation;
The relation used for calculating \(\mathbf{\Delta G^0}\) of the reaction when the temperature is 702 K is:
\(\Delta G^0_{702 \ K} = \Delta H^0_{xn} - T \Delta S^0_{rxn}\)
where;
\(\Delta G^0_{702 \ K} =\) Gibbs free energy of the reaction at 702 K
\(\Delta H^0_{xn}\) = standard enthalpy of the reaction = -116.2 kJ/mol
\(\Delta S^0_{rxn}\) = standard entropy of the reaction = -146.6 J/mol/K
Temperature T = 702 K
\(\Delta G^0_{702 \ K} = -1162. \ kJ/mol - 702 \ K ( -146.6 \ J/mol. K (\dfrac{1 \ kJ }{1000 \ J})\)
\(\Delta G^0_{702 \ K} = -1162. \ kJ/mol - 702 \ K ( 0.1466 \ kJ/mol.K})\)
\(\Delta G^0_{702 \ K} = -13.2868 \ kJ/mol.K}\)
\(\mathbf{\Delta G^0_{702 \ K} = -13.29 \ kJ/mol.K}}\)
Thus \(\mathbf{\Delta G^0_{702 \ K} = -13.29 \ kJ/mol.K}}\) and the reaction is spontaneous