3.08 moles of carbon are in the sample.
What are moles?
A Mole is defined as a chemical unit, defined to be 6.022 x 10 23 ( Avogadro's Constant) entities. In science, this is often usually molecules or atoms. The mass of a mole is the gram formula mass of a substance.
Their averages are equal
moles of carbons / 5 = moles of o
19/5 = moles of c
3.08 = moles of c
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From a bag containing 5 nickels, 8 dimes, and 7 quarters, 5 coins are drawn at random and all at once. what is the probability of getting 2 nickels, 2 dimes, and 1 quarter? how many total electrons
The probability of getting 2 nickels, 2 dimes, and 1 quarter is; 0.1264
What is probability ?The area of mathematics known as probability deals with numerical descriptions of how likely it is for an event to happen or for a claim to be true. The probability of an occurrence is a number between 0 and 1, with 1 representing certainty and 0 representing impossibility of the event.
The higher the probability of an event, the more probable it is to occur. Tossing a fair (unbiased) coin is a straightforward illustration. Since there are no other possible outcomes and the coin is fair, the probability of both "heads" and "tails" is half. Since there are no other conceivable outcomes, the probability of either "heads" or "tails" is equal to one.
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you have been given four substances that are all white solids at room temperature. List three specific test that you could perform to figure out whether they are ionic or molecular compunds.
Answer:
The three tests to determine whether the solid is ionic or molecular compound are explained below
What is a Compound?
Chemical substances known as compounds are made up of two or more elements that are bonded chemically in a certain order. Chemistry is the study of the chemical, physical, and structural characteristics of material entities. Realizing that not all gases, liquids, and solids are created equal is crucial.
Explanation:
Firstly, the sample of the substance is taken in a test tube and heated over a flame. If the substance melts, then it is a covalent simple molecular compound and if no melting occurs then it may be either ionic or covalent ionic compound.
Secondly, Dissolve the substance in water or any other polar solvent. If it dissolves, then it can be either ionic or covalent simple molecular compound.
Next, electrolysis can be performed with the aqueous solution, if sample remains unmelted, dissolved in water and conducts electric current, then it is an ionic compound.
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John ordered 1.25 kg of zinc for an experiment when he weighed it, he measured 1.13 kg what is the percent error of Johns measurement
How many chlorine molecules
are in 6.5 moles of chlorine?
Answer:
6.5 x ( 6.02x 10^23)= 3.913 x10^24
Explanation:
questionyou heat two substances, a and b. both substances change color. when cooled, both substances return to their original colors.what most likely happened in this situation?
Two substances, a and b were heated. Both substances change color. when cooled, both substances return to their original colors.
What is a physical change and examples?Changes within the size or form of matter are examples of physical change. Physical changes include transitions from one state to a different , like from solid to liquid or liquid to gas. Cutting, bending, dissolving, freezing, boiling, and melting are a number of the processes that create physical changes.
Why it's a physical change?Physical changes occur when objects or substances undergo a change that doesn't change their chemical composition. This contrasts with the concept of chemical process in which the composition of a substance changes or one or more substances combine or break up to form new substances.
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a 52-gram sample of water that has an initial temperature of 10.0 °c absorbs 4,130 joules. if the specific heat of water is 4.184 j/(g °c), what is the final temperature of the water? 11 °c 19 °c 29 °c 51 °c
The final temperature of the water is 29 degrees.
What is heat energy?
The results of the movement of minute particles known as atoms, molecules, or ions in liquids, solids, and gases are nothing but heat. heat can be transferred from one substance to another and the flow because of the temperature difference between two objects is known as heat.
It is given that,
Mass of sample of water, m = 52 grams
Initial temperature, Ti = 10 degree
Heat absorbed, Q = 4,130 J
The specific heat of water is 4.184 J/(g C)
So, the ultimate temperature of the water is 28.98-degrees.
The option C is correct.
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of the 20 standard amino acids, only is not optically active. the reason is that its side chain .
Glycine is the only amino acid that is not optically active because it does not have a carbon chiral center.
The simplest amino acid is glycine. Because it is the only amino acid without an asymmetrical carbon atom, it differs from all the other amino acids. Glycine is therefore optically inactive. No stereoisomers exist in it. This amino acid is necessary for the manufacture of bile acids, porphyrins, creatine phosphate, and other amino acids as well as nucleic acids.
When compared to the other amino acids, glycine is integrated into proteins and enzymes at a rate of 7.5%, making it the second most prevalent amino acid on a molar basis. Glycine shares a similar ability to block neurotransmitter impulses in the central nervous system with gamma-aminobutyric acid and glutamic acid.
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examine the following order of elution of compounds containing certain functional groups from fastest to slowest, and indicate which mistake has been made.hydrocarbons, olefins, ethers, amines, ketones, aldehydes, esters, alcohols, aromatics, and carboxylic acidsamines and aromatics are switched.ethers and esters are switched.alcohols and aromatics are switched.aromatics and esters are switched.aldehydes and esters are switched.
The Elution sequence of compounds containing certain functional groups from the fastest to the slowest is hydrocarbons, olefins, ethers, halo carbons, aromatics, ketones, aldehydes, esters, alcohols, amines and acids.
Elution:
Elution in organic and analytic chemistry refers to the process in which one material is extracted from another material by washing it with the help of a solvent.
In an elution sequence, regardless of the polarity of the compounds, the solvent which is more polar, its chemicals elutes faster. Therefore, amending the polarity of the solvent will not change the order of elution of compounds. It might seem contradictory as a polar solvent seems to convey polar compounds beyond the non-polar compounds.
Contemplating the solvents and the chemicals will fight for the stationary phase locations conductive to help us visualize the intention. Slow elution would be created by the molecules which were remained to attach to the stationary phase due to poor ability of a less polar solvent to compete. Molecules and a polar solvent successfully asserted for the stationary phase locations.
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How is force and gravity work together with simple objects?
Force and gravity work together with simple objects exert an equal attractive force
Gravity or gravitational force is the force of attraction between any two objects in the universe and the force of attraction depends on the mass of the object and the square of the distance between them and it is by far the weakest known force in nature the size of the gravitational force is proportional to the masses of the objects and weakens as the distance between them increases and both objects exert an equal attractive force on each other and falling object is attracting the earth with the same size force as the earth is attracting it
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molecular views of the reactant solutions for a precipitation reaction are shown below (with ions represented as spheres and water molecules omitted): 1. which compound is dissolved in beaker a: [ select ] 2. which compound is dissolved in beaker b: [ select ] 3. name the precipitate when solutions a and b are mixed. [ select ] 4. what is the sum of the coefficients of the net ionic equation (enter a whole number such as 0, 1, 2, 3 etc.) [ select ]
1. Li2CO3 is dissolved in beaker A
2. CaCl2 is dissolved in beaker B
3. When A and B are mixed is a white colour precipitate is formed of
CaCO3.
4. The sum of the coefficients of the net ionic equation is 0.
What is precipitation reaction?
In a precipitation process, two soluble salts in aqueous solution mix, and one of the byproducts is an insoluble salt known as a precipitate.
The precipitate can be removed from the liquid by centrifugation, decantation, or filtration, or it can remain suspended in the solution and fall out on its own. The term "supernate" refers to the liquid that is left over after a precipitate occurs.
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someone please help i don’t understand this
Answer: m = 179.4 g
Explanation:
Answer:
26.5385
Explanation:
Directions: Classify each property as physical or chemical.
1. Sulfur is yellow
2. Petroleum gas ignites when exposed to air and fire
3. A diamond is a rated a 10 on the Mohs hardness scale
4. Rubidium has a density of 1.53 g/ml
5. Hydrogen has a mass of 1.00784 g
6. melting point of water is 32 degree F
7. Copper can be transformed into wire.
8. 5 ml of water
9. Zinc metal reacts quickly with hydrochloric acid to produce Hydrogen gas
10. The element sulfur smells like rotten eggs.
11. 5 grams of NaCl
12. Aluminum is flatten to make aluminum foil
13. Your old bicycle has rusted.
1. Sulfur is yellow (chemical)
2. Petroleum gas ignites when exposed to air and fire (chemical)
3. A diamond is a rated a 10 on the Mohs hardness scale (physical)
4. Rubidium has a density of 1.53 g/ml (physical)
5. Hydrogen has a mass of 1.00784 g (physical)
6. melting point of water is 32 degree F (physical,)
7. Copper can be transformed into wire. (physical).
8. 5 ml of water. (physical)
9. Zinc metal reacts quickly with hydrochloric acid to produce Hydrogen gas (chemical)
10. The element sulfur smells like rotten eggs.(chemical)
11. 5 grams of NaCl. (physical)
12. Aluminum is flatten to make aluminum foil (physical).
13. Your old bicycle has rusted (chemical).
Difference between physical and chemical change
The major difference between a physical and chemical change is that a chemical change involves the formation of entirely new substance while a physical change does not create a new substance.
Classification of the substances into physical and chemical substance
1. Sulfur is yellow (chemical, change in color through air reaction is chemical change)
2. Petroleum gas ignites when exposed to air and fire (chemical, combustion is chemical change)
3. A diamond is a rated a 10 on the Mohs hardness scale (physical, no new substance is formed)
4. Rubidium has a density of 1.53 g/ml (physical, no new substance is formed)
5. Hydrogen has a mass of 1.00784 g (physical, no new substance is formed)
6. melting point of water is 32 degree F(physical, no new substance is formed)
7. Copper can be transformed into wire. (physical, no new substance is formed).
8. 5 ml of water. (physical, no new substance is formed)
9. Zinc metal reacts quickly with hydrochloric acid to produce Hydrogen gas (chemical, new substance is formed)
10. The element sulfur smells like rotten eggs.(chemical, new substance is formed which is hydrogen sulfide)
11. 5 grams of NaCl. (physical, no new substance is formed)
12. Aluminum is flatten to make aluminum foil (physical, no new substance is formed).
13. Your old bicycle has rusted (chemical, new substance is formed)
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What are the requirements for utilizing simple distillation to seperate this liquid mixture?
If the components have boiling points that are significantly different from one another, a straightforward distillation is utilized.
What is distillation process?
The technique of selectively boiling and condensing to remove the constituents or chemicals from a liquid mixture is known as distillation, or classical distillation. Heating solid materials to create gaseous products is known as dry distillation.
Distillation is the process of dividing up a mixture into its constituent parts according to their various boiling points. Alcohol purification, desalination, crude oil refinement, and the creation of liquefied gases from air are a few applications for distillation. In the Indus Valley, distillation has been used by humans at least since 3000 BC.
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What is the reducing agent in the redox reaction represented by the following cell notation? cd(s) | cd2 (aq) || li (aq) | li(s)
In the given redox reaction, the reducing agent is Cd (s).
When a chemical species "donates" an electron to an electron receptor, it is referred to as a reducing agent in chemistry (also referred to as a reductant, electron donor or reducer).
A reducing agent, which is often in one of its lesser oxidation states, serves as the electron donor. The loss of one electron in the redox reaction results in the oxidation of a reducing agent.
At the anode, oxidation reaction occurs:
[tex]Cd (s) \rightarrow Cd^2^+ (aq) + 2e^-[/tex]
At the cathode, reduction reaction occurs:
[tex]2Li^+ (aq) + 2e^- \rightarrow 2Li (s)[/tex]
The overall redox reaction is:
[tex]Cd (s) + 2Li^+ (aq) \rightarrow Cd^2^+ (aq) + 2Li (s)[/tex]
As it is known that the reducing agent is the one that undergoes oxidation in a redox reaction, therefore, Cd (s) is the reducing agent.
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Which molecule has the higher molar mass? which molecule would have the higher rate of effusion?
The rate of effusion and the square root of molar mass is inversely proportionate .
Which molecule could have the higher rate of effusion?The lighter a gas is, the quicker it will rave; the heavier a gas is, the quieter it will effuse. Of all the choices, helium (He) has the lowest molecular weight (atomic weight in this case), so it will have the most elevated rate of effusion.
The molar mass of nitrogen is more inferior than the molar mass of oxygen. Hence, the rate of effusion of nitrogen is more elevated than the rate of effusion of oxygen.
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Chlorine has two naturally occurring isotopes, 35cl and 37cl. What is the mass number of each? how many protons, neutrons, and electrons are present in each?.
The mass number [tex]_{17} Cl^{35}[/tex] is 35.
The mass number [tex]_{17} Cl^{37}[/tex] is 37.
isotopes of [tex]_{17} Cl^{35}[/tex] contains. and isotopes [tex]_{17} Cl^{37}[/tex] contain.
protons=17 protons= 17
neutrons= 18 neutrons=20
electrons= 17 electrons=17
Define Isotopes
Isotopes are two or more atom types that share the same atomic number (number of protons in their nuclei) and position in the periodic table (and, therefore, belong to the same chemical element). However, isotopes have different nucleon numbers (mass numbers) because they have varying numbers of neutrons in their nuclei. All isotopes of a given element have nearly identical chemical properties but differ in terms of atomic mass and physical characteristics.
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Balance the following chemical equation __Fe2O3 + __ AI—> __ Fe + __AI2O3
Answer:
Fe2O3 + 2Al -> 2Fe + Al2O3
Answers to 33-38 pls
Answer:
-5
Explanation:
For what I did was:
Switch the numbers
(35-33)
Do the math
Then add a negative because the smaller number is first meaning it will be a negative number
How did the maple syrup interact with the water and oil?
____________ helps digest proteins in the stomach. group of answer choices bile salt pepsin nahco3 pepsinogen trypsin
Pepsin Pearls helps digest proteins in the stomach.
What is the composition of pepsin?Pepsin is a monomer (chain protein) made up of two similar folding domains separated by a deep cleft. Pepsin's catalytic site is formed at the domain junction; each domain contains two aspartic acid residues.Here are some important pepsin advantages:
Aids the body in breaking down difficult-to-digest proteins.Indigestion and leaky gut are avoided.Increases the production of bile.Assists with liver detoxification.Improves nutrient absorption.Aids in the prevention of nutritional deficiencies.Pepsin is a stomach enzyme that aids in the digestion of proteins found in food. Pepsin is secreted by gastric chief cells as an inactive zymogen known as pepsinogen. Parietal cells in the stomach lining secrete hydrochloric acid, which lowers the stomach's ph. Pepsin is activated by a low pH (1.5 to 2).To learn more about Pepsin Pearls refer to
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Read the description and find the vocabulary term that matches it.
Description
15.
16.
17.
18.
19.
20.
21.
22.
23.
study of processes that take place in
living organisms
systematic approach to solving a
scientific problem
variable that you change during an
experiment
the study of matter and how it reacts
deals with mechanism, rate, and
energy transfer
proposed explanation for an observation
well-tested explanation for a broad set
of observations.
concise statement summarizing results
of many experiments
variable that is observed during an
Vocabulary Term
a. theory
b. chemistry
c. scientific law
d. dependent or responding variable
e. scientific method
f. biochemistry
g. physical chemistry
h. independent or manipulated variable
i. hypohthesis
15. F
16. E
17. H
18. B
19. G
20. i
21. A
22. C
23. D
You're welcome :)
A solid piece of lead has a mass of 38.20 g and a volume of 3.37 cm3. from these data, calculate the density of lead in si units (kilograms per cubic meter).
The solid pieces of lead with a mass of 38.20 g has a density of 11,340 Kg/ m3
The density formula and the procedure we will use is:
ρ = m/v
Where:
v= volumeρ= densitym= massInformation about the problem:
ρ (kg/m3)= ?v = 3.37 cm3m = 38.20 gApplying the density formula, we get:
ρ = m/v
ρ = 38.20 g/ 3.37 cm3
ρ(g/cm3) = 11.34 g/cm3
Converting the density from (g/cm3) to (kg/m3), we get:
11.34 g/cm3 * (1 kg/1000g) * (1000000 cm3/1 m3) = 11,340 Kg/ m3
11.34 g/cm3 is equivalent to 11,340 Kg/ m3
What is density?It is a physical quantity that expresses the ratio of the body mass to the volume it occupies.
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you use 25% ethyl acetate (an ester) in hexane to run a tlc and obtain a single round spot with an rf of 0.9 for the main compound. what would you do?
We need to do is to try 35% ethyl acetate to see the results.
What is chromatography?The term chromatography has to do with the process of separation in which there is a stationary phase and a mobile phase. The stationary phase in thin layer chromatography is the adsorbent while the mobile phase is the solvent mixture.
The solvent mixture would determine the extent of separation. We know that if the compound is polar, then we need a mixture of a polar solvent and a nonpolar solvent.
The RF of 0.9 implies that the separation was minimal. Thus, what we need to do is to try 35% ethyl acetate to see the results.
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Missing parts;
you use 25% ethyl acetate (an ester) in hexane to run a tlc and obtain a single round spot with an rf of 0.9 for the main compound. what would you do?conclude that the sample is pure.assume that tlc will be useless and find a different way to see if the sample if pure.try a completely different set of solvents, as ethyl acetate and hexanes will never work.try 10% ethyl acetate to see the results.try 35% ethyl acetate to see the results.
According to the law of conservation of energy, which statement must be true?
OA. There is only one form of energy.
OB. Energy that is transformed is neither destroyed nor created.
OC. Energy can change only from nuclear to chemical.
OD. The total energy in a system can only increase over time.
Answer:
B. Energy that is transformed is neither destroyed nor created.
Hope this helps :)
Explanation:
This is what the Law of Conservation of Energy says, "Energy that is transformed is neither destroyed nor created."
When following the scientific method, why would asking a subjective question be
an inappropriate part of the procedure?
•A subjective question means it has little or nothing to do with the observation.
•A subjective question would negate any findings from the observation.
•A subjective question is too specific and needs to be simplified to conduct an
experiment.
•A subjective question deals with opinions, morals, and emotions and is not suited
for science.
The statement 'A subjective question deals with opinions, morals, and emotions and is not suited for science' is the explanation of why a subjective question is inappropriate for the scientific procedure (Option 4).
Why opinions are inaccurate for the scientific method?Opinions are inaccurate for the scientific method because any subjective point of view may bias the process to obtain knowledge, which always must be tested by experimentation.
In conclusion, the statement 'A subjective question deals with opinions, morals, and emotions and is not suited for science' is the explanation of why a subjective question is inappropriate for the scientific procedure (Option 4).
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the freezing point of pure benzene (c₆h₆) is 5.49 °c. the freezing point of a solution made using toluene (c₇h₈) in benzene is determined to be -13.0 °c. what is the molality of the toluene? (kf benzene
The molality of the solution is 3.6 molal
What is the boiling point?The boiling point is the temperature at which the pressure of the system is equal to the atmospheric pressure. Now we know that freezing point depression is one of the colligative properties.
We have that;
ΔT = K m i
ΔT = Freezing point depression
m = molality of the solution
i = Van't Hoff factor
i =1 because the solute is molecular
ΔT = 5.12 oC/molal * m * 1
We can get ΔT from; Freezing point of pure solvent - Freezing point of solution
= 5.49 °c - ( -13.0 °c) = 18.49°c
m = ΔT /k * 1
m = 18.49°c/5.12 oC/molal
m = 3.6 molal
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If the ph outside the cell decreases, would you expect the amount of amino acids transported into the cell to increase or decrease?
A decrease in pH means a rise in positively charged H+ ions, and a rise in the electrical gradient across the membrane. The transport of amino acids into the cell will increase.
How do amino acids move across the cell membrane?
The amino acids are diffused across the cell wall by facilitated diffusion with the help of symporter proteins present in the plasma membrane. These also are called sodium-dependent amino acid transporters.
What do the cells do with the amino acids?
The gastrointestinal system breaks all proteins down into their amino acids so that they can enter the bloodstream. Cells then use the amino acids as building blocks to create enzymes and structural proteins.
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identify all possible types of intermolecular forces that can form between particles of each substance below. (select all that apply.) (a) cs2 dipole-dipole interactions hydrogen bonding interactions ion-dipole interactions london dispersion forces (b) ch2br2
All possible types of intermolecular forces that can form between particles of :
(a) CS2: London dispersion forces
(b) CH2Br2: Dipole-dipole interaction and H-bonding
What are intermolecular forces?
Intermolecular forces, frequently abbreviated to IMF, are the appealing and repulsive forces that stand up among the molecules of a substance. These forces mediate the interactions among man or woman molecules of a substance. Forces additionally exist among the molecules themselves and those are together called intermolecular forces. Intermolecular forces are specifically answerable for the bodily traits of the substance. There are 5 varieties of intermolecular forces. They are as follows-
Dipole-Dipole InteractionsIon-Dipole InteractionsIon Induced Dipole InteractionsDipole Induced Dipole InteractionDispersion Forces or London ForcesThus, al the types of intermolecular forces possible between particles of :
(a) CS2: London dispersion forces
(b) CH2Br2: Dipole-dipole interaction and H-bonding
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The most common technique used to measure oxygen consumption in an exercise physiology laboratory is?
The most common technique used to measure oxygen consumption today is termed open-circuit spirometry.
What is open-circuit spirometry?The method of performing spirometry known as "open circuit" entails the subject inhaling as much air as possible from the surrounding environment, putting the mouthpiece in his or her mouth, and then exhaling either slowly (SVC) or quickly (FVC) until the end-of-test criterion is reached. With devices based on wedge bellows, bell, water seal, or rolling seal cylinder/piston-based volume sensing spirometers, open circuit approach is frequently utilized.
The method of measuring spirometry known as "closed circuit" spirometry involves having the subject place a flow transducer in their mouth, breathe normally for two to three tidal breaths (rest breathing), take a maximal inspiration or expiration through the flow transducer, and then slowly inhale or exhale.
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red gold is a gold‑copper alloy used to make jewelry. a piece of jewelry made of red gold weighs 9.47 g9.47 g and has a volume of 0.715 cm30.715 cm3 . gold has a density of 19.3 g/cm 319.3 g/cm3 and copper has a density of 8.96 g/cm 38.96 g/cm3 . calculate the percentage by mass of each metal in the jewelry. assume the total volume of the jewelry is the sum of the volumes of the two metals it contains.
Red gold is a gold‑copper alloy used to make jewelry.
Red gold is an alloy created by combining pure gold and copper without any or very little silver.
Here the percentage by mass of gold
= (100/9.47) × 5.71832496
= 60.3835794 %
The percentage by mass of copper
= (100/9.47) × 3.75167504
= 39.6164207 %
The pieces of jewelry ( weight 9.47g) contains 60.3835794 % Gold and 39.6164207 % copper.
What is red gold?
Red gold is an alloy created by combining pure gold and copper without any or very little silver.
Since gold is yellow—at least pure gold is—there is no such thing as red gold, the phrase "red gold" is truly an oxymoron.
A homogenous blend of two or more metallic elements is referred to as an alloy. Alloys are valuable because they can be designed to have unique properties that are impossible to achieve with pure metals. Silver and copper are the two ad metals that are used most frequently in gold alloys. In the past, the majority of gold alloys were composed of copper, silver, and all three metals, along with other trace metals. These mixes typically yield a pleasing yellow hue that resembles pure gold.
Let's assume the pieces of jewelry (weight 9.47g) contains X g gold and Y g copper.
Now according to the question,
X+Y = 9.47 .......... (1)
Again we know that, density= mass/volume
So,
X/19.3 + Y/8.96 = 0.715 ............. (2)
Or, X/19.3 = 0.715 - Y/8.96
Or, X = 13.7995 - 19.3Y/8.96
If we put the value of X in the equation (1). Then
13.7995 - 19.3Y/8.96 + Y = 9.47
Or, Y(19.3/8.96 - 1) = 4.3295
Or, Y = 4.3295 /1.15401786
Or, Y = 3.75167504
Now, from equation (1).
X+ 3.75167504 = 9.47
Or, X = 5.71832496
Here the percentage by mass of gold
= (100/9.47) × 5.71832496
= 60.3835794 %
The percentage by mass of copper
= (100/9.47) × 3.75167504
= 39.6164207 %
The pieces of jewelry ( weight 9.47g) contains 60.3835794 % Gold and 39.6164207 % copper.
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