The amount of copper (in moles) in a 35.8-g pure copper sheet = 0.564 moles.
Given:
Mass = 35.8 g
Molar mass of copper = 63.5 g/mol
It home contains copper, a lovely and practical metallic element, both in its pure form and as chemical compounds. The International System of Units uses the mole (symbol: mol) as the unit of material quantity (SI). The amount of a substance determines how many elementary entities of that substance are present in an object or sample.
Moles can be calculated using the formula:
Number of moles = Mass/ Molar mass
Putting values in above equation, we get
Number of moles = 35.8 g / 63.5 g/mol
Number of moles = 0.564 moles
So, The amount of copper (in moles) in a 35.8-g pure copper sheet = 0.564 moles.
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need help on chemistry homework
Use the density of palladium (d = 12.1 g/cm3) to determine the volume in cubic centimeters of a sample that has a mass of 44.1 ounces.
(1 ounce = 28.35 grams)
The volume of the palladium is 103.3 cubic centimeters.
What is the density?The term density has to do with the ratio of the mass to the volume of a substance. We can see here that the density of the palladium has been given as 12.1 g/cm3. However, the mass of the substance has been given in ounces.
We know that;
1 ounce = 28.35 grams
44.1 ounces = 44.1 ounces * 28.35 grams/1 ounce
= 1250.23 g
Density = mass/volume
volume = mass/Density
volume = 1250.23 g/12.1 g/cm3
volume = 103.3 cubic centimeters
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Name 3 sources for ions in seawater
The facts you find in reference source that support your data in an experiment
The facts you find in reference source that support your data in an experiment is known to be called research.
What is known to be a research?Research is known to be a term that is defined as as a kind of "creative and methodical form of activity done to improve the body of knowledge.
It entails the objective gathering, organizing, and analysis of data in order to improve comprehension of a subject or issue.
The Research is described as the thoughtful analysis of studies pertaining to a certain issue or problem utilizing scientific methodologies.
Therefore, since Research is a methodical inquiry, one can say that he facts that you find in reference source that support your data in an experiment is known to be called research.
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would you expect an atom to have a charge?
Answer:
An atom consists of a positively charged nucleus, surrounded by one or more negatively charged particles called electrons. The positive charges equal the negative charges, so the atom has no overall charge; it is electrically neutral.
The specific gravity of granite is 2.80. If the weight density of water is 62.4 lbs/ft3, what is the weight density of granite?
Based on the specific gravity of granite, the weight density of granite is 174.72 lbs/ft³.
What is specific gravity?The specific gravity of a substance is the ratio of the density of the given substance to that of the ratio of a reference substance usually water.
Specific gravity is also known as relative density of that substance.
Specific gravity is dimensionless since it is the ratio of two similar quantities.
Considering the given data:
The specific gravity of granite is 2.80.
This means that the ratio of the weight density of granite and that of water is 2.80.
The weight density of water = 62.4 lbs/ft³
The weight density of granite = ?
2.80 = weight density of granite/ weight density of water
The weight density of granite = 2.80 * weight density of water
The weight density of granite = 2.80 * 62.4 lbs/ft³
The weight density of granite = 174.72 lbs/ft³
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express the number 0.000114 in scientific notation.
its correct
How many electrons must each atom gain or lose to acquire an electron configuration identical to the noble gas nearest to it in atomic number?
Li lose one electron to acquire an electronic configuration. I must accept one electron, N accept three electron and Al lose three electron to acquire noble gas electronic configuration.
For Li,
Li belongs to first group of the periodic table and have 3 as atomic number. So, it lose one electron to acquire stable electronic configuration like as Helium.
For I,
I belongs to 17th group of the periodic table and have 53 as atomic number. So, it accept one electron to acquire stable electronic configuration like as Xenon.
For N,
N belongs to 15th group of the periodic table and have 7 as atomic number. So, it gain three electron to acquire stable electronic configuration like as Neon.
For Al,
Al belongs to 3rd group of the periodic table and have 13 as atomic number. So, it lose three electron to acquire stable electronic configuration like as Neon.
Thus, we concluded that Li lose one electron to acquire an electronic configuration. I must accept one electron, N accept three electron and Al lose three electron to acquire noble gas electronic configuration.
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Which of the following statements is FALSE in regards to herpes?
A. A symptom of herpes is flu-like symptoms.
B. Herpes simplex symptoms will occur in about a week of contraction.
C. Only herpes simplex I affects the face as a cold sore and herpes simplex Il affects the genitals.
D. There is no cure for HSV.
Answer:
B. is false
Explanation:
-there is no cure for hsv,
-herpes simplex I does affect the face as a cold sore, and herpes simplex II does affect the genitals
- a symptom of herpes can be flu like symptoms, everyone is different, some people don't even have any symptoms at all
Dr. R needs to make 153 mL of a 1.25 M solution of ZrCl2. What mass of ZrCl2 is needed to prepare this solution?
The mass of ZrCl₂ needed to prepare the solution, given the data is 30.98 g
How to determine the mole of ZrCl₂We'll begin by obtaining the mole of ZrCl₂. This can be obatined as follow:
Volume = 153 mL = 153 / 1000 = 0.153 LMolarity = 1.25 MMole of ZrCl₂ =?Mole = Molarity x Volume
Mole of ZrCl₂ = 1.25 × 0.153
Mole of ZrCl₂ = 0.191 mole
How to determine the mass of ZrCl₂ neededWe can obtain the mass of ZrCl₂ needed to prepare the solution as follo:
Molar mass of ZrCl₂ = 91.22 + (35.5 × 2) = 162.22 g/molMole of ZrCl₂ = 0.191 mole Mass of ZrCl₂ =?Mass = mole × molar mass
Mass of ZrCl₂ = 0.191 × 162.22
Mass of ZrCl₂ = 30.98 g
Thus, the mass of ZrCl₂ needed to prepare the solution is 30.98 g
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Which of the following is an intensive property of a sample of water?
A. Mass
B. Molar mass
C. Number of moles
D. Volume
Molar mass is an intensive property of a sample of water.
The molar mass of a certain chemical entity is its mass per unit quantity (symbol M, SI unit kgmol1). Always identify the chemical in question in accordance with the definition of the mole. A substance's molar mass is the volume of the material that contains one mole of the substance. Its basic definition is the weight of a single mole of a substance. The atomic mass of each substance is multiplied by the subscript of that element in the chemical formula to determine the molar mass.
One mole of a specific compound or material has a mass of 1 molar. We are aware that the number of moles in a compound (n) can be expressed as the ratio of the compound's given mass to its molar mass. This is measured in g mol1, the standard unit. However, the SI unit, kg mol 1, is quite uncommon. The amount of particles in 1 mole of the substance is equal to the number of atoms present in 12g of the 12C isotope.
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A + B <-------> AB is an example of what type of chemical reaction
Answer:
Synthesis reaction
Explanation:
In synthesis reactions, two or more atoms/molecules combine to form a larger molecule.
These reactions follow the general structure: A + B <-----> AB.
For the reaction
Ti(s)+2F2(g)→TiF4(s)
compute the theoretical yield of the product (in grams) for each of the following initial amounts of reactants.
1. 4.0 g Ti , 4.0 g F2
2. 2.2 g Ti , 1.8 g F2
3. 0.225 g Ti , 0.283 g F2
The theoretical yields in each case are;
1) 13.64 g
2) 5.82 g
3) 0.92 g
What is the theoretical yield ?We know that the stoichiometry of the reaction is the tool that we could use to obtain the parameters that has to do with a given reaction. We have the reaction; [tex]Ti(s)+2F_{2}(g)------- > TiF_{4} (s)[/tex]
1) Number of moles of Ti = 4.0 g/48 g/mol = 0.08 moles
Number of moles of [tex]F_{2}[/tex] = 4.0 g/38 g/mol = 0.11 moles
If 1 mole of Ti reacts with 2 moles of [tex]F_{2}[/tex]
0.08 moles reacts with 0.08 moles * 2 moles/1 mole
= 0.16 moles
[tex]F_{2}[/tex] is the limiting reactant
Mass of [tex]TiF_{4}[/tex]= 0.11 moles * 124 g/mol = 13.64 g
2) Number of moles of Ti = 2.2 g /48 g/mol = 0.045 moles
Number of moles of [tex]F_{2}[/tex]= 1.8 g/38 g/mol = 0.047 moles
If 1 mole of Ti reacts with 2 moles of [tex]F_{2}[/tex]
0.045 moles of Ti reacts with 0.045 moles * 2 moles/1 mole
= 0.09 moles
[tex]F_{2}[/tex] is the limiting reactant
Mass of TiF4 = 0.047 moles * 124 g/mol = 5.82 g
3) Number of moles of Ti = 0.225 g/48 g/mol = 0.0047 moles
Number of moles of [tex]F_{2}[/tex] = 0.283 g/38 g/mol = 0.0074 moles
If 1 mole of Ti reacts with 2 moles of [tex]F_{2}[/tex]
0.0047 moles of Ti reacts with 0.0047 moles * 2 moles/1 mole
=0.0094 moles
[tex]F_{2}[/tex] is the limiting reactant
Mass of [tex]TiF_{4}[/tex]= 0.0074 moles * 124 g/mol = 0.92 g
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A student wants to measure out a 0.163 mol sample of barium fluoride (BaF2). How many grams of is this?
Additional Information:
If needed, Molar Mass of BaF2 is 175.34 g/mol
If needed use 6.022 x 1023 for Avogadro's number.
Format your answer:
With three significant figures
Include the correct unit.
Answer:
28.6 grams BaF₂
Explanation:
To find the amount of BaF₂ in grams, you need to multiply the given value (moles) by the molar mass. The molar mass is a ratio which describes the mass (g) of BaF₂ per every 1 mole. It is important to arrange the ratio in a way that allows for the cancellation of units (moles should be in the denominator).
Molar Mass (BaF₂): 175.34 g/mol
0.163 moles BaF₂ 175.34 grams
---------------------------- x ----------------------- = 28.58042 = 28.6 grams BaF₂
1 mole
suppose that you and a friend see brightly colored pigeons like these at a nature park. because pigeons are usually gray and white, you both wonder where these colors came from suddenly, your friend says i have a theory these birds must get their colors from eating food that has the same colors
The correct answer is no. The explanation given by my friend is not a scientific theory, that's why it is not correct.
What is a scientific theory?A scientific theory is a well-organized explanation that frequently includes a scientific hypothesis and scientific principles to explain a collection of facts or events in the natural world.
Scientists use the word "theory" a little differently than the public, according to Jaime Tanner, a biology professor at Boston's Emerson College. Most people use the word "theory" to describe an opinion or hunch, but in science, the term relates to how we interpret the data.
A scientific theory is a phenomenon that has been observed and verified. For a declarative assertion to be elevated to the status of a theory, it must first have been tested in the form of experiments by several researchers and found to be accurate. A statement can be considered a hypothesis if it is stated on the basis of perception, with little or no experimental evidence to back it up. A theory is something entirely different.
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4. The following precipitation reaction can be used to determine the amount of copper ions dissolved in solution.
A chemist added 5.00 × 10−2 L of a solution containing 0.173 mol L−1 Na3PO4(aq) to a 5.00 × 10−2 L sample containing CuCl2(aq). This resulted in a precipitate. The chemist filtered, dried, and weighed the precipitate. If 1.21 g of Cu3(PO4)2(s) were obtained, and assuming no copper ions remained in solution, calculate the following:
a. the concentration of Cu2+(aq) ions in the sample solution.
b. the concentrations of Na+(aq), Cl−(aq), and PO43−(aq) in the reaction solution (supernatant) after the precipitate was removed.
a) In the sample solution, concentration of Cu^2+ ions = 0.191 mol L-1
b) Concentration of Na+ = 0.0865 mol L-1
Concentration of Cl- = 0.1908 mol L-1
Concentraion of PO42- = 0.0199 mol L-1
Reaction of Na3PO4 and CuCl2 gives 1.21 g of Cu3(PO4)2 as a precipitate. But after precipitation, no Cu2+ ions are left which means, the number of moles of Cu2+ present will be 3 × 3.18 mmol = 9.54 mmol ( same for CuCl2 as it contains only 1 Cu+ ion) ( From the formula 1 mole of Cu3(PO4)2 will give 3 moles of Cu2+ ions). the concentration of Cu2+ ions in the sample will be 9.54 × 10^-3/ 5.00 ×10^-2 = 0.191molL-1Now in the final mixture, we have 0.1 L of solvent. ( 5.00 ×10^-2 + 5.00 ×10^-2 ).Number of moles of Na+ = Volume × Molarity = 5.00 × 10^-2 L ×0.173 mol L-1 = 8.65 mmol ( As it is not present in the precipitate, we have to take the initial number of moles)Concentration of Na+ = 8.65 × 10^-3/ 0.1 == 0.0865molL-1Number of moles of Cl - = 2 × 9.54 = 19.08 mmol ( From the formula one mole of CuCl2 gives 2 moles of Cl- )Concentration of Cl- = 19.08× 10^-3 0.1 = 0.1908molL-1 Number of moles of PO42- = Number of moles in Na3PO4 - Number of moles in the precipitate = 8.35 - 2 ×3.18 = 1.99 mmol ( In Na3PO4 there is only one PO42- whereas in the Cu3(PO4)2 there are 2 PO42-Concentration of PO42- = 1.99× 10-³ / 0.1= 0.0199molL-1To know more about Concentration visit : https://brainly.com/question/17639158
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Atoms of C-12, C-13, and C-14 have the
same number of protons but a different number of neutrons.
same number of neutrons but a different number of protons.
same number of electrons but a different number of protons.
same number of protons but a different number of electrons.
Answer:
same number of protons but different number of neutrons.
Which of these is a way to tell if something is a compound?
Answer:
Answer: Image 3 is a compound.
Explanation: A compound is something that consists of two or more different elements bonded chemically.
A molecule is formed when two or more elements combine chemically.
An element is described as something which cannot be broken down by any chemical means.
We are given 4 images.
Image 1 is an element as it is showing the shell structure of Oxygen (O) element.
Image 2 is an element as only 1 element is known that is Magnesium (Mg).
Image 3 is a compound as in the structure 2 elements are shown which is bonded together. Elements present in this are Carbon (C) and Oxygen (O).
Image 4 is a molecule as in the structure 2 H-atoms combine chemically, but it cannot be considered as compound as the two elements are not different.
Explanation:
Explain how fomation of lines indicate the presence of energy level
Calculate the number of nitrogen atoms in a 80.0 g sample of dinitrogen tetroxide (N₂O4).
Be sure your answer has a unit symbol if necessary, and round it to 3 significant digits.
The number of atoms of nitrogen in an 80.0 g sample of dinitrogen tetroxide (N₂O4) is 1.047 * 10²⁴ atoms.
What is the number of nitrogen atoms in an 80.0 g sample of dinitrogen tetroxide (N₂O4)?The number of nitrogen atoms in an 80.0 g sample of dinitrogen tetroxide (N₂O4) is calculated as follows:
Molar mass of N₂O4 = 92 g/mol
Moles of N₂O4 in 80.0 g sample = 80/92
Moles of N₂O4 in 80.0 g sample =0.87 moles
Moles of nitrogen in the sample = 0.87 * 2
Moles of nitrogen in the sample = 1.74 moles
1 mole of nitrogen contains 6.0 * 10²³ atoms
Number of atoms of nitrogen = 1.74 * 6.0 * 10²³ atoms
Number of atoms of nitrogen = 1.047 * 10²⁴ atoms
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1.Differences between ions and charge??
Explain how the interdependent relationship between advances in technology and scientific discoveries has enhanced
our understanding of the universe.
The interdependent relationship between advances in technology and scientific discoveries has enhanced our understanding of the universe. schooling, merchandising, and different multidisciplinary efforts by way of fostering higher information about the multidimensional nature of research.
Development in technological know-how and technology studies seeks to improve the techniques of technology and technology studies, Clinical expertise is used to create new technologies. New technology regularly allows scientists to explore nature in distinct ways and make new discoveries.
Technological know-how is the have a look at the natural world through a scientific approach i.e. collecting facts via a systematic procedure. And era is in which we observe science to create gadgets that can solve issues and perform distinct responsibilities. technology is literally the utility of science.
Society drives technological improvements and scientific inquiry. technology offers us a perception of what form of technology we should doubtlessly create and a way to create them, even as technology allows us to behave in addition to medical studies.
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What is the mass of phosphorus in a 45 kg person?
Answer:
Mass of phosphorus = (435kg)(0.01) = 0.45 kg
Scrub all right, had to drink a poisonous substances that paralyzes body resulting in death what is most likely the exclamation for how the substance produced paralysis
The body's muscles become increasingly paralyzed as a result of tetrodotoxin's interference with the signaling process from nerves to muscles. Toxic exposure to tetrodotoxin may be lethal.
Scrub all right, had to drink a poisonous substances that paralyzes body resulting in death.
What is most likely the exclamation for how the substance produced paralysis?
Tetrodotoxin (TTX), a neurotoxin, is extremely poisonous.
Tetrodotoxin is a sodium channel blocker. It stops neurons from firing action potentials by clinging to the voltage-gated sodium channels in nerve cell membranes and obstructing sodium ions from entering the neuron, which are crucial for an action potential's rising phase.
Due to the neurological system's inability to communicate, muscles are unable to contract in response to nerve inputs. It works by selectively blocking sodium channels.
The majority of its occurrences are in the livers and sex organs of several fish species, such as puffer fish, globefish, and toadfish (order Tetraodontiformes) (gonads).
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Please explain and answer
To have only two significant figures we must have to add a decimal point and two zeros.
What are significant figures?The term significant figures refers to the figures that we could assign a place value. These are the figures that could be assigned a place in a string of digits. The nonzero values to which it is possible that we could give a place can be called a significant figure.
Having established that, we can see that the number 52 has two significant figures. The number 5.209 has three significant figures. If we want the value 52 to retain having only two significant figures then we have to add a decimal point and two zeros.
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Initially, 0.880 mol of A is present in a 3.00 L solution.
2A(aq)↽−−⇀2B(aq)+C(aq)
At equilibrium, 0.150 mol of C is present. Calculate K.
The equilibrium constant is 0.026.
What is the equilibrium constant of the reaction?Let us recall that the equilibrium constant is a number that shows us the extent to which reactants are converted into products. In other words, a large positive value of the equilibrium constant indicates that most of the reactants have been converted into products.
Initial concentration of A = 0.880 mol /3.00 L = 0.29 M
Equilibrium concentration of C = 0.150 mol /3.00 L = 0.05 M
We can set up the ICE table thus;
2A(aq) ⇄ 2B(aq) + C(aq)
I 0.29 M 0 0
C -2x +2x +x
E 0.29 - 2x 2x 0.05 M
Where
x = 0.05
At equilibrium;
[A] = 0.29 - 2(0.05 ) = 0.19 M
[B] = 2(0.05) = 0.1 M
[C] = 0.05 M
K = [B] [C] /[A]
K = 0.1 * 0.05/ 0.19
K = 0.026
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Calculate the moles of ammonia present in a 4.206 g sample of ammonia which has a molar mass of 17.30 g/mol
Answer:
The moles of ammonia present will be "0.274 moles".
Molar mass:
A particular element's molar mass would be the mass of either the material that contains 1 mole of material. It should be the weight of such mole of something in basic words.
To determine the molar mass, multiply the atomic mass per each substance by the component's subscript throughout the chemical equation.
Given:
Weight in grams, w = 4.652 g
Molar mass, m = 17.030 g/mol
We know,
→ Number \ of \ moles (n)= \frac{Weight(w)}{Molar \ mass(m)}Number of moles(n)=
Molar mass(m)
Weight(w)
By substituting the values,
n = \frac{4.652}{17.030}n=
17.030
4.652
= 0.274=0.274 moles
Thus the response above is right
The correct symbol for Cl with 20 neutrons and 14 electrons is
Select one:
a. 1735 CI+
b.1735 Cl
C. 1737C15+
d. 1735Cl
e. 1737 C1³+
E. The oxidation number of chlorine with 14 electron is written as 17, 37 CL⁺³.
What is oxidation number?Oxidation number of an atom/ion is the number of electrons an atom/ion that the molecule has either gained or lost compared to the neutral atom.
What is oxidation number of chlorine?Chlorine is a non metal with atomic number of 17 (17 electron, and 17 proton).
Chlorine also has an oxidation number of -1.
When the number of electron of the chlorine has been reduced to 14, it implies that the chlorine ion has been reduced by losing 3 electrons.
The oxidation number of chlorine with 14 electron is written as follows;
= CL (14) = 17 CL⁺³
mass number = 17 + 20 = 37
= 17, 37 CL⁺³
Thus, the oxidation number of chlorine with 14 electron is written as 17, 37 CL⁺³.
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What is the relationship between KMT and Sea Level Rise?
CER format
3-4 sentences
Sea level may rise as a result of the expansion of seawater and the melting of land-based ice due to a warming environment.
What is the sea level?The sea level is the fundamental level for calculating height and depth on Earth. Since the ocean is one continuous body of water, its surface tends to seek a constant level. The sea surface is not actually level due to winds, currents, river discharges, fluctuations in gravity, and temperature.
Why is sea level important?People are impacted by sea level changes through flooding, the inability of rivers to empty into the ocean due to the sea being too high, and the surge of seawater onto the land during storms. Our drinking water and the ability to cultivate crops could be harmed if sea water gets into farms and reservoirs.
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If 7.50 mol of NH₃ and 8.15 mol of O₂ react in the following reaction, how many moles of H₂O will be formed? 4 NH₃ (g) + 5 O₂ (g) → 4 NO (g) + 6 H₂O (g)
If 7.50 mol of NH₃ and 8.15 mol of O₂ react in the following reaction. The number of moles of H₂O that will be formed is 9.84 moles.
What are moles?The mole is a SI unit of measurement that is used to calculate the quantity of any substance.
Using the molar coefficients in the balanced equation, 6 moles of water are formed for every 4 moles of NH₃.
6 moles of water are formed for every 5 moles of O₂.
So (7.5 moles NH₃)(6 moles H₂O)/4 moles NH₃) = 11.25 moles water
For (8.20 moles O₂) / (6 moles H₂O)(5 moles O₂) = 9.84 moles H₂O.
So O₂ is the limiting reagent, and we can only make as much product as allowed by the limiting reagent.
Thus, the number of moles is 9.84 moles of water.
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A 25.0-g sample of pure iron at 85 °C is dropped into
75 g of water at 20. °C. What is the final temperature
of the water-iron mixture?
A sample of 25.0-g pure iron at the 85 °C is dropped into 75 g of water at 20°C. 22.25 °C is the final temperature of the water-iron mixture.
What is Specific Heat Equation ?The specific heat equation is represented as
Q = mcΔT
where,
Q = heat energy in Joules
m = mass of substance
c = specific heat
ΔT = change in temperature in K
For iron given that
m = 25 g
c = 0.45 J/g°C
T₁ = 85°C
Now by putting the values in the above formula then we get
Q₁ = mcΔT
= 25 × 0.45 × (T₂ - 85)
= 11.25 × (T₂ - 85)
For water given that
m = 75 g
c = 4.184 J/g°C
T₁ = 20°C
Now,
Q₂ = mcΔT
= 75 × 4.184 × (T₂ - 20)
= 313.8 × (T₂ - 20)
Now,
Heat is generated by the iron = Heat is gained by the water.
Q₁ = -Q₂
11.25 × (T₂ - 85) = - 313.8 × (T₂ - 20)
325.05 T₂ = 7232.25
T₂ = 22.25 °C
22.25 °C is the final temperature of the water-iron mixture.
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