Answer:
the rate constant of the reaction is approximately 0.0021 s^-1.
Explanation:
To calculate the rate constant of a first-order reaction, we can use the following equation:
ln([A]t/[A]0) = -kt
Where [A]t is the concentration of reactant at time t, [A]0 is the initial concentration of reactant, k is the rate constant, and t is time.
Given that the reaction is 45% complete after 400 s, we can assume that [A]t/[A]0 = 0.55 (since 100% - 45% = 55%). Plugging this value into the equation above, we get:
ln(0.55) = -k(400)
Solving for k, we get:
k = -ln(0.55)/400
k ≈ 0.0021 s^-1
A first-order reaction is 45% complete after 400 s. Therefore, 0.0021 s⁻¹ is the rate constant of the reaction.
What is rate constant?The chemical kinetics rate law, which connects the molecular concentration of reacting substances to reaction rate, uses the rate constant as a proportionality factor. The letter k in an equation designates it, which is also referred to as either the resultant rate constant and reaction rate coefficient.
The link among the molecular concentration of reactants with the rate for a chemical reaction is shown by the proportionality constant k. Utilising the molecular weights of each of the reactants with the sequence of the reaction, the rate constant can be calculated experimentally. As an alternative, the Arrhenius equation can be used to compute it.
ln([A]t/[A]0) = -kt
[A]t/[A]0 = 0.55
ln(0.55) = -k(400)
k = -ln(0.55)/400
k ≈ 0.0021 s⁻¹
Therefore, 0.0021 s⁻¹ is the rate constant.
To know more about rate constant, here:
https://brainly.com/question/20305871
#SPJ2
What is the normality of the solution that results when 4.0g of Al(NO3)3 (MW = 213.0) is dissolved in enough water to give
250mL of solution? What is the molarity of the solution?
the normality of the solution that results when 4.0g of Al(NO₃)₃ (MW = 213.0) is dissolved in enough water to give 250mL of solution the molarity of the solution is 0.0751 M.
To calculate the normality and molarity of the solution, we need to know the number of moles of Al(NO₃)₃ in the solution.
The number of moles can be calculated as:
moles = mass / molar mass
where mass is the mass of Al(NO₃)₃ and molar mass is the molecular weight of Al(NO₃)₃
Substituting the given values, we get:
moles = 4.0 g / 213.0 g/mol = 0.01878 mol
The volume of the solution is given as 250 mL, which is equivalent to 0.25 L.
The normality of the solution is defined as the number of equivalents of solute per liter of solution. For Al(NO₃)₃, each mole of the compound produces 3 moles of ions, so the number of equivalents of Al(NO₃)₃ is:
equivalents = moles x 3
Substituting the value of moles, we get:
equivalents = 0.01878 mol x 3 = 0.05634 eq
The normality can now be calculated as:
normality = equivalents / volume
Substituting the given values, we get:
normality = 0.05634 eq / 0.25 L = 0.225 N
Therefore, the normality of the solution is 0.225 N.
The molarity of the solution is defined as the number of moles of solute per liter of solution. The number of moles of Al(NO₃)₃ in 250 mL of solution is the same as the number of moles in 1 L of solution, which is 0.01878 mol. Therefore, the molarity of the solution is:
molarity = moles / volume
Substituting the given values, we get:
molarity = 0.01878 mol / 0.25 L = 0.0751 M
Learn more about solution here:
https://brainly.com/question/30665317
#SPJ1
Please solve whichever you can PICTURE INCLUDED! show work pls
The molar entropy from the question that we have here is 85.1kJ/K.mol as shown.
What is the molar entropy?The molar entropy of a substance can be calculated by dividing the total entropy of the substance by the number of moles present. The entropy of a substance can be determined experimentally by measuring its heat capacity or by analyzing its thermodynamic behavior under different conditions.
We know that;
Entropy = ΔH/T
= 1.6 * 10^4 * 10^3J/mol/187.95 K
= 85.1kJ/K.mol
For the bromide ion;
Rate = 5/1 * 2.7 * 10^-3 mol/s
= 1.35 * 10^-2 mol/s
Learn more about entropy:https://brainly.com/question/13135498
#SPJ1
using the balanced chemical reaction equations, and the energies of the reactants and products, calculate the combustion of glucose O2 = 498kj/1 mol o2, 1598kj/1mol H2O = 934kj/1mol H2O, use correct units
One mole of glucose burns to produce several gases. [tex]6600kJ[/tex] of power. Another way to put it is that the burning of glucose releases [tex]6600KJ/mol[/tex] thermal energy.
What's a straightforward explanation of combustion?A chemical reaction between two or more substances, typically containing oxygen, is called combustion. It results in the production of light and heat in the form of a flame.
The correct chemical formula for the burning of glucose
[tex]C6H12O6 + 6O2 \rightarrow 6CO2 + 6H2O[/tex]
We can determine the change in enthalpy for this reaction by using the values provided for the enthalpies of formation of the reactants and products:
Reactants:
[tex]C_6H_1_2O_6[/tex] : not given
[tex]O2: -498 kJ/mol \times 6 = -2988 kJ/mol[/tex]
Products:
[tex]CO_2[/tex]: not given
[tex]H2O -1598 kJ/mol \times 6 = -9588 kJ/mol[/tex]
[tex]\Delta H = (\epsilon products) - (\epsilon reactants)[/tex]
[tex]\Delta H = (-9588 kJ/mol + 0) - (0 + -2988 kJ/mol)[/tex]
[tex]\Delta H = -6600 kJ/mol[/tex]
Therefore, One mole of glucose burns to produce several gases. [tex]6600kJ[/tex] of power. Another way to put it is that the burning of glucose releases [tex]6600KJ/mol[/tex] thermal energy.
Learn more about combustion here:
https://brainly.com/question/15117038
#SPJ9
What volume will 1.02 mol of carbon monoxide gas occupy at STP?
1.02 mol of carbon monoxide gas will occupy a volume of approximately 22.8 liters at STP.
At STP (standard temperature and pressure), the temperature is 273.15 K (0°C) and the pressure is 1 atmosphere (atm). The molar volume of a gas at STP is 22.4 L/mol.
Using the ideal gas law, we can calculate the volume of 1.02 mol of carbon monoxide gas at STP: PV = nRT
where:
P = pressure = 1 atm
V = volume (unknown)
n = moles = 1.02 mol
R = gas constant = 0.0821 L·atm/(mol·K)
T = temperature = 273.15 K
V = (nRT)/P
putting the values,
V = (1.02 mol)(0.0821 L·atm/(mol·K))(273.15 K) / (1 atm)
V = 22.4 L/mol
V = 22.8 L
To know more about carbon monoxide here
https://brainly.com/question/11608350
12. 50cm³ of alcohol is mixed with 50cm³ of water. The volume of the mixture is 97cm³. Which o the following is the best explanation for this observation red?
The alcohol and water molecules sharing the same space leads to a more compact arrangement of the molecules in the combination, which is the best explanation for the observed drop in volume.
When alcohol and water are combined, what happens to the volume?In this illustration, adding water to alcohol results in a final volume that is roughly 10% lower than the combined volumes of the two liquids. The "vanishing volume" results from variations in how the solvent molecules are packed in the mixture compared to the pure components.
Why does the volume drop when alcohol and water are combined?Alcohol molecules slide into the spaces between the water molecules as it dissolves, reducing the volume.
To learn more about volume of alcohol visit:
brainly.com/question/29939079
#SPJ9
If 50cm³ of alcohol is mixed with 50cm³ of water. The volume of the mixture is 97cm³. What is the best explanation for this observation?
A. Water evaporates leading to decrease in volume of the mixture
B. Water and alcohol molecules react and form a compact solution
C. Alcohol being volatile evaporates and decreases the volume of the mixture
D. The alcohol and water molecules sharing the same space leads to the decrease in volume of the mixture
Give the IUPAC name for: image attached
The IUPAC name of the given compound is 1-bromo-3-ethylpentane.
What are the steps involved in writing IUPAC name?IUPAC (International Union of Pure and Applied Chemistry) naming is a system used to give standardized names to chemical compounds. The steps involved in doing IUPAC naming are as follows:
1. Identify the longest carbon chain: The parent chain is the longest continuous chain of carbon atoms in the molecule.
2. Number the carbon atoms: The carbon atoms in the parent chain are numbered starting from the end nearest to the substituent, and the substituents are given numbers based on the carbon to which they are attached.
3. Identify and name the substituents: Substituents are groups of atoms that replace hydrogen atoms on the parent chain. They are named according to their functional groups.
4. Write the name: The name of the compound is written by listing the names of the substituents in alphabetical order, along with their position on the parent chain.
5. Add prefixes and suffixes: Prefixes are added to indicate the number of substituents on the parent chain, and suffixes are added to indicate the functional group present.
6. Check the name: The final step is to check the name for accuracy and consistency with IUPAC rules.
It's important to note that the naming of complex organic compounds can involve additional rules and naming conventions beyond these basic steps.
Learn more about carbon here:
https://brainly.com/question/22530423
#SPJ9
What is the base conjugate acid pair in this balanced equation NH3+HNO3→NH4+ + NO3-
Answer:
The base conjugate acid pair is NH3 and NH4+.
How many grams of solute are in the following solution?
250mL of 0.39M acetic acid, CH3CO2H
There are 5.85 grams of acetic acid (CH3CO2H) in the given solution.
To calculate the grams of solute in the given solution, we first need to calculate the number of moles of solute (acetic acid) present in the solution.
We know the volume of the solution (250 mL) and the molarity of the solution (0.39 M). We can use the following equation to calculate the number of moles of solute:
moles of solute = molarity × volume (in liters)
First, we need to convert the volume from milliliters to liters:
250 mL = 0.250 L
Now we can use the equation to calculate the number of moles of acetic acid:
moles of CH3CO2H = 0.39 M × 0.250 L = 0.0975 moles
Finally, we can use the molar mass of acetic acid to convert the number of moles to grams:
molar mass of CH3CO2H = 60.05 g/mol
grams of CH3CO2H = moles of CH3CO2H × molar mass of CH3CO2H
grams of CH3CO2H = 0.0975 moles × 60.05 g/mol = 5.85 g.
Learn more about acetic acid here:
https://brainly.com/question/15202177
#SPJ1
I need help with these questions. If you help me i will mark you as most brainiest :) Thank you, have a great day!
Al, Cu, and Zn, Al are the metals in equations 1 and 2, respectively. Since aluminium is ranked higher on the activity series than copper, it can substitute for copper in chemical reactions.
Which metal in the experiment using metals and water reacts violently and ignites?Metal and Water Reaction: An Introduction Because of the intense interactions that certain metals have with water, such potassium and sodium, they will ignite if left outside.
Which metal reacts slowly when exposed to cold water yet swiftly when exposed to steam?Magnesium is therefore the most reactive of the listed metals, and as a result, its pace of reaction will be the quickest (to react with steam). Magnesium does not react with cold water, whereas metals with strong reactivity like potassium (K), sodium (Na), and calcium (Ca) do.
To know more about aluminium visit:-
https://brainly.com/question/25869623
#SPJ1
what is the current produced y 120 volts passing through a resistance of 0.2 ohms?
Calculate the Kelvin temperature to which 21.0 L of a gas at 34°C would have to be heated to change the volume to 41.0 L. The pressure and number of particles remain constant.
In order to convert the volume from 21.0 L to 41.0 L while maintaining the same pressure and particle number, the gas would need to be heated to a temperature of 580.49 K.
When the amount of moles and pressure are both constant?According to Boyle's law, the pressure and volume of a gas follow an inverse relationship when the gas's temperature and molecular composition are both constant.
This problem can be solved using the coupled gas law, which connects a gas's pressure, volume, and temperature:
(P1 V1) / T1 = (P2 V2) / T2
In this problem, we are given P1 = P2, V1 = 21.0 L, V2 = 41.0 L, and T1 = 34°C. We want to find T2 in Kelvin.
First, we need to convert T1 from Celsius to Kelvin:
T1 = 34°C + 273.15
T1 = 307.15 K
Next, we can rearrange the combined gas law to solve for T2:
T2 = (P2 V2 T1) / (P1 V1)
Substituting the given values, we get:
T2 = (1 atm * 41.0 L * 307.15 K) / (1 atm * 21.0 L)
T2 = 580.49 K
To know more about gas law visit:-
https://brainly.com/question/24519415
#SPJ1
sample gas has a pressure of 6.8 kPa at 539K. If the temperature decreases to 211K, then what will be the new pressure?
Gay-Lussac's Law-
[tex] \:\:\:\:\:\:\star\longrightarrow \underline{\sf \boxed{\sf \dfrac{P_1}{T_1}=\dfrac{P_2}{T_2}}}[/tex]
[tex] \:\:\:\:\:\:\star\longrightarrow \sf \underline{P_2=\dfrac{P_1 \:T_2}{T_1}}[/tex]
Where-
P₁ is the initial pressure.T₁ is the initial temperatureP₂ is the final pressure.T₂ is the final temperatureAs per question, we are given -
P₁ = 6.8 KPaT₁ =539 KT₂= 211KNow that we are given all the required values, so we can put them into the formula and solve for P₂:-
[tex] \:\:\:\:\:\:\:\:\:\:\:\:\longrightarrow \sf P_2=\dfrac{P_1 \:T_2}{T_1}\\[/tex]
[tex] \:\:\:\:\:\:\:\:\:\:\:\:\longrightarrow \sf P_2=\dfrac{6.8\times 211}{539}\\[/tex]
[tex]\:\:\:\:\:\: \:\:\:\:\:\:\longrightarrow \sf P_2 = \dfrac{1434.8}{539}\\[/tex]
[tex] \:\:\:\:\:\:\:\:\:\:\:\:\longrightarrow \sf P_2 = 2.661966.........\\[/tex]
[tex]\:\:\:\:\:\: \:\:\:\:\:\:\longrightarrow \sf\underline{ P_2 = 2.7 \:KPa}\\[/tex]
Therefore, If the temperature decreases to 211K, then the new pressure will become 2.7 KPa.
Plants capture the sun's energy and make food in the process of photosynthesis. Only about 0.1 percent of the sun's energy is captured by plants. Plants take carbon dioxide and water and, using the energy from sunlight, convert it into glucose (food) and oxygen. About one-half of the energy absorbed by plants is used right away. The other half is stored in plants as energy-containing food (carbohydrates).
A green maple leaf with the chemical equation of photosynthesis below it, its reactants above and to the left and its products to the right of it.
A green maple leaf with the chemical equation of photosynthesis below it. The chemical equation has reactants of coefficient 6, CO subscript 2, +, coefficient 6, H subscript 2, 0, a yields arrow with the label light above it and chlorophyll below it, and products of coefficient 6 C subscript 6, H subscript 12, 0 subscript 6, + coefficient 6 0 subscript 2. Above the leaf is a down arrow pointing to the center of the left. To the left of this arrow is a rain cloud labeled water and to the right is a beaming sun labeled light. To the left of the lead is a grey cloud of gas labeled carbon dioxide with an arrow pointing toward the leaf. To the right of the lead are two parallel arrows the top of which points to the label glucose and the bottom to the label oxygen.
2. How do you think energy from the sun ends up in the crust, tomato sauce, cheese, and meat on a slice of pizza?
The food chain that produces elements like the crust, tomato sauce, cheese, and meat on a pizza begins with the energy that plants absorb from the sun through photosynthesis.
What is photosynthesis?Green plants, algae, and some microorganisms transform solar energy into chemical energy in the form of organic compounds like carbohydrates through a process called photosynthesis. Light energy is absorbed by pigments, chiefly chlorophyll, which is present in the chloroplasts of plant cells, during photosynthesis. Next, using this energy, glucose (a form of sugar) and oxygen are produced from carbon dioxide and water.
By photosynthesis, plants use the sun's energy to create carbohydrates (like glucose). Following the consumption of these carbohydrates by herbivores, predators subsequently consume these carbs, and so on.
When it comes to a pizza, the wheat used to form the crust was probably grown in a field where it employed photosynthesis to take in energy from the sun. Like with other vegetables used as toppings, the tomatoes used to prepare the sauce were probably also grown in a field. Pizza's cheese is formed from milk, which comes from cows who eat grass and other plants that have undergone photosynthesis to receive solar energy. Last but not least, any meat added as a garnish originated from creatures that also ate vegetables for fuel.
In a sense, the sun's energy, which plants use to produce food, including the components in a pizza, is eventually harnessed by photosynthesis.
To know more about photosynthesis, visit:
brainly.com/question/29775046
#SPJ1
An unknown element contains 11 protons, 11 neutrons and 12 electrons, which of the following options do you think the unknown element is?
Answer:Sodium
Explanation:Sodium has 11 protons, 11 nuetrons, and 12 electrons
What volume would a 1.75 mole sample of O2 gas occupy, if it had a pressure of 2.7 atm, and a temperature of 35 °C?
Answer:
9 ans
Explanation:
cold 20 -11 =9 ans
summer 20-11=9 ans
Original Claims: In general, what types of substances tend to be acidic?
Fruit Juices
Beverages (Coffee/Soda/Milk)
Cleaning Products
Digestive Juices
Answer in this format.
Restate original Claim here. This claim was ______ (supported/ not supported) by the claim because ________.(give a brief description of the correct claim using terms pH, COLOR and pH PAPER)
For example, from the evidence,_____ (use THREE specific examples from your evidence of the pH value and color of the pH paper to support your answer)
Restate original Claim here. This claim was supported by the claim because the evidence showed that acidic substances have a pH value less than 7 and cause the pH paper to turn a certain color.
What is pH?
pH is a measure of the acidity or basicity of a solution. It is defined as the negative logarithm of the concentration of hydrogen ions (H+) in a solution. pH values range from 0 to 14, where 0 is the most acidic, 7 is neutral, and 14 is the most basic. A change of one unit in pH represents a tenfold change in the concentration of hydrogen ions.
For example, from the evidence, fruit juices such as lemon juice have a pH value of around 2-3 and turn the pH paper a red color, which indicates acidity. Beverages such as coffee and soda also have a low pH value, around 4-5, and turn the pH paper a slightly red color. Cleaning products such as vinegar have a pH value of around 2-3 and turn the pH paper a red color as well.
Learn more about pH from given link
https://brainly.com/question/26424076
#SPJ1
you take a 25g chalk piece outside and draw for 5 min the chalk weighs 5g after how many molecules of chalk did you leave outside on the concreate. the chalk is CaCO3.
AnswerTherefore, you left approximately 1.202 x 10^23 molecules of CaCO3 on the concrete after drawing with a 25g chalk piece outside for 5 minutes.
Explanation:
To solve this problem, we need to use the concept of conservation of mass, which states that matter cannot be created or destroyed, only transformed from one form to another. Therefore, the total mass of the chalk before and after drawing must be equal.
The mass of the chalk before drawing is 25 g. After drawing for 5 minutes, the mass of the chalk is 5 g. Therefore, the mass of chalk that was used for drawing is:
25 g - 5 g = 20 g
Next, we need to convert the mass of the chalk used to the number of molecules. The molar mass of CaCO3 is 100.09 g/mol, which means that one mole of CaCO3 contains 6.022 x 10^23 molecules.
To calculate the number of molecules of chalk used for drawing, we can use the following steps:
Calculate the number of moles of CaCO3 used:
20 g / 100.09 g/mol = 0.1998 mol
Calculate the number of molecules of CaCO3 used:
0.1998 mol x 6.022 x 10^23 molecules/mol = 1.202 x 10^23 molecules
Discuss two pre-requisite skills needed for students to learn the process of writing balanced chemical and ionic equations
Answer:
Explanation:Two pre-requisite skills needed for students to learn the process of writing balanced chemical and ionic equations are:
1. Understanding of the periodic table and elements: Students must have a solid foundation in the periodic table, including recognizing elements by their symbols and understanding their properties, groups, and electron configurations.
2. Knowledge of chemical bonding and compound formation: Students should be familiar with the different types of chemical bonds (ionic, covalent, and metallic) and know how to construct chemical formulas for compounds based on their component elements and valence electrons.
What is the volume of a 0.5 M solution of HCl if it contains 36.5 grams of solute?
Molar mass (H -1 g/mol)(Cl - 35.5 g/mol)
___ L (Answer Format: X)
Answer: 2 L or 2000 mL
Explanation:
A 1 molar (1 M) solution is equal to 1 mole of the solute dissolved in 1 L of solution.
For HCl (mw 36.5) 1 mole = 36.5 g
1 molar (1 M) = 1 mole/1 liter (or 36.5 g/L)
So
0,5 M = 1 mole/x
(x is the volume we are solving for)
Multiply both sides by x and you get
0.5x=1
Now multiple both sides by 2
X=2
So it’s 2L volume
Acetylene (C₂H₂) gas is often used in welding torches because of the very high heat produced when it reacts with oxygen (O₂) gas, producing carbon dioxide
gas and water vapor. Calculate the moles of water produced by the reaction of 2.2 mol of acetylene. Be sure your answer has a unit symbol, if necessary, and
round it to the correct number of significant figures
How many moles of gas are in a 34.2 L container at 1 atm of pressure and 273.15 K?
Answer:
1.525834 (1.53 when accounting for significant figures).
Explanation:
This problem relies on the Ideal Gas Law, PV = nRT, where P is pressure, V is volume, n is moles, R is a specific constant, and T is temperature. In this problem, we are solving for n, moles, so we would rewrite it as n = PV/RT. Since the units here are moles, liters, atmospheres, and kelvin, R would be the value in atmosphere liter per mole kelvin, or 0.0821. From here, you just enter the values in the fraction and calculate.
For the significant figures, I followed the measurement of 34.2 L, giving 3, although an argument could be made for 1 significant figure from 1 atm, I imagine your professor would want something more specific than 2.
Standard vinegar solutions are about 5% acetic acid by mass. What is the molarity of a 5% vinegar solution? The molar mass of acetic acid is 60.052 g/mol. The density of the solution is 1.01 g/mL.
Explanation:
To calculate the molarity of the vinegar solution, we first need to calculate the number of moles of acetic acid present in one liter of the solution.
Since the density of the solution is 1.01 g/mL, one liter of the solution will have a mass of 1.01 kg.
The mass of acetic acid in one liter of the solution can be calculated as follows:
mass of acetic acid = 5% × 1.01 kg = 0.0505 kg
The number of moles of acetic acid can be calculated using its molar mass:
moles of acetic acid = mass of acetic acid / molar mass of acetic acid
moles of acetic acid = 0.0505 kg / 60.052 g/mol
moles of acetic acid = 0.000841 mol
Therefore, the molarity of the vinegar solution is:
molarity = moles of acetic acid / volume of solution in liters
molarity = 0.000841 mol / 1 L
molarity = 0.000841 M
So, the molarity of a 5% vinegar solution is approximately 0.000841 M.
Calculate the mass of chlorine in 25 kg of CFCl3.
Can someone explain the steps please thanks
The mass of chlorine in 25kg of [tex]CFCl_3[/tex] is 6,435g where mass is a measure of the amount of matter in an object. It is measured in kilograms (kg) or grams (g).
The mass of [tex]CFCl_3[/tex] = 25kg
The molecular weight of [tex]CFCl_3[/tex] (also known as Freon-11) is = 137.37 g/mol.
It means one mole of [tex]CFCl_3[/tex] = 137.37 g.
Since chlorine is an element, one mole of chlorine is equal to its atomic weight, which is 35.45 g/mol.
Therefore, number of moles 25 kg of [tex]CFCl_3[/tex] contains =
(25 kg) / (137.37 g/mol) = 182.4 mol of [tex]CFCl_3[/tex].
To calculate the mass of chlorine in 25 kg of [tex]CFCl_3[/tex], we need to multiply the number of moles of chlorine by its atomic weight.
The mass of chlorine in 25 kg of [tex]CFCl_3[/tex] is = 182.4 mol * 35.45 g/mol = 6,435 g of chlorine.
Hence, the mass of chlorine in 25 kg of [tex]CFCl_3[/tex] is 6,435 g.
To learn more about mass click here https://brainly.com/question/11622869
#SPJ1
Which term describes the energy the reactant molecules must meet for a reaction to progress?
O average kinetic energy of reactants
O enthalpy
O activation energy
O average kinetic energy of products
Answer:
Activation Energy
Explanation:
Activation energy is the minimum amount of energy that reactant molecules must possess in order to undergo a chemical reaction. as it is necessary to break the bonds of between the molecules of the reactants.
hope you find this easy to understand....
Have any questions? Write in the comments.
give me brainliest if you found this answer useful
Part A
Identify the problem that the cold pack must address.
The cold pack is designed to address the problem of pain and swelling due to injury or inflammation.
What is cold pack?A cold pack, also known as a cold compress, is a medical device designed to provide cold therapy to a specific area of the body. It typically consists of a gel-filled plastic bag or pouch that is placed in the freezer for a period of time to lower its temperature.
When applied to the affected area, the cold temperature helps to reduce blood flow, which in turn reduces inflammation, swelling, and pain. Cold packs are commonly used to treat minor injuries such as sprains, strains, and bruises, as well as to alleviate pain and swelling associated with chronic conditions like arthritis.
Learn about cold pack here https://brainly.com/question/7745193
#SPJ1
How much heat has to be added to 235 g of iron at 25.0°c to raise the temperature of the iron to 250.0°c?
Answer:
23205 J or 2.37 × 10⁴ J or 23.7 kJ
Explanation:
The amount of heat required to change the temperature of a substance can be calculated using the formula: q = mcΔT, where q is the heat added, m is the mass of the substance, c is its specific heat capacity, and ΔT is the change in temperature.
The specific heat capacity of iron is 0.44 J/g K1. So, to raise the temperature of 235 g of iron from 25.0°C to 250.0°C (a change of 225°C), you would need to add:
q = (235 g) × (0.44 J/g K) × (225 K) = 23205 J
So you would need to add 23205 joules of heat to raise the temperature of 235 g of iron from 25.0°C to 250.0°C.
why doesn't catalyst shift the equilibrium position?
Answer:
catalysts do not shift the equilibrium position of a chemical reaction because they do not affect the free energy difference between reactants and products
Explanation:
To understand this better, let's consider an example. The Haber process is used to produce ammonia from nitrogen and hydrogen gas:
N2(g) + 3H2(g) ⇌ 2NH3(g)
This reaction is exothermic, meaning that it releases heat. According to Le Chatelier's principle, adding heat to an exothermic reaction will shift the equilibrium position towards the reactants (N2 and H2). Conversely, removing heat from the system will shift the equilibrium position towards the products (NH3).
Now, let's say we add a catalyst to this reaction. The catalyst will speed up both the forward and reverse reactions equally, without affecting their relative rates. This means that although the reaction will reach equilibrium faster with a catalyst present, it will still reach the same equilibrium position as it would without a catalyst.
Label each change as gradual or rapid:
Hurricane = ________
Volcanic eruption = ________
Regrowth after volcanic eruption = ________
Flooding = ________
Seasonal changes = ________
Oceans increasing temperature = ________
Global warming = ________
Fire = ________
Hurricane = Rapid
Volcanic eruption = Rapid
Regrowth after volcanic eruption = Gradual
Flooding = Rapid
Seasonal changes = Gradual
Oceans increasing temperature = Gradual
Global warming = Gradual
Fire = Rapid
Answer:
rapid
rapid
gradual
rapid
gradual
gradual
gradual
rapid
Explanation:
Consider the reaction. 2Pb(s)+O2(g)⟶2PbO(s) An excess of oxygen reacts with 451.4 g of lead, forming 338.4 g of lead(II) oxide. Calculate the percent yield of the reaction.
The reaction's per cent yield is 69.5%.
Calculation-We must compare the actual yield of the reaction to the theoretical yield of the reaction to get the per cent yield of the reaction.
First, we need to calculate the amount of Pb reacted using the given mass of Pb:
mass of Pb = 451.4 g
The molar mass of Pb is 207.2 g/mol, so the number of moles of Pb reacted is:
moles of Pb = mass of Pb / molar mass of Pb
moles of Pb = 451.4 g / 207.2 g/mol
moles of Pb = 2.179 mol
The theoretical yield of PbO can be calculated using the molar mass of PbO:
mass of PbO = moles of PbO × molar mass of PbO
mass of PbO = 2.179 mol × 223.2 g/mol
mass of PbO = 486.6 g
Therefore, the theoretical yield of PbO is 486.6 g.
The per cent yield of the reaction is:
per cent yield = (actual yield / theoretical yield) × 100%
per cent yield = (338.4 g / 486.6 g) × 100%
percent yield = 69.5%
to know more about per cent yield here;
brainly.com/question/19463038
#SPJ1
help please been asking for days LOLLL keep getting the wrong answers.
Answer:
22.24°C.
Explanation:
The change in temperature of the iron can be calculated using the formula: ΔT = Q / (m * c), where ΔT is the change in temperature, Q is the heat added, m is the mass of the substance and c is the specific heat capacity.
Substituting the given values into the formula: ΔT = 115 cal / (47.0 g * 0.11 cal/g⋅°C) ≈ 22.24°C
So, the change in temperature of the iron is 22.24°C.