Help me indicate whether OXYGEN will gain or lose electrons to get a full outer shell and how many electrons they will need to gain or lose

Step 1 - Balancing the neutralization reaction

Since perchloric acid (HClO4) is an acid and calcium hydroxide (Ca(OH)2) is a base, the reaction will be a neutralization. Note that HClO4 is a monoprotic acid, whereas Ca(OH)2 will liberate, by dissociation, two OH(-) groups. We will need thus two HClO4 (to liberate two H(+) and fully neutralize the OH(-) groups):

Step 2 - Discovering how many moles of Ca(OH)2 have reacted

Since the exercive gives us the volume (V) as well as the concentration ([ ])of Ca(OH)2, we can discover how many moles (n) of it reacted by using the following relation:

We already know that [Ca(OH)2] = 0.149 mol/L and V = 26 ml (0.026 L). The number of moles will be thus:

Step 3 - Discovering how many moles of HClO4 have reacted

Looking at the equation in step 1 again:

We can see that 2 moles of HClO4 react with 1 mole of Ca(OH)2. This is a fixed proportion which means that we'll always need two times more HClO4 than Ca(OH)2.

The number of moles of HClO4 that reacted will be thus:

The number of moles of HClO4 that reacted is thus 7.74*10(-3) moles.

Step 4 - Discovering the required volume of HClO4

Now that we know how many moles of HClO4 reacted and given that we also know the concentration (0.224 M), we can discover the volume by using the same formula as in step 2:

Substituting the values on the equation, we get:

The required volume will be thus 34 ml.

The pH of the 1.63 M solution of methylamine is 10.56.

The pH of the 1.63 M solution of methylamine is calculated from the equation of the dissociation reaction  as follows:

H₃CNH₂ (aq) + H₂O (l) ---> H₃CNH₃ (aq) + OH⁻ (aq)

pKb of H₃CNH₂ = 3.66

Kb of H₃CNH₂ = 10⁻³°⁶⁶ = 2.19 * 10⁻⁴

The [OH¯] is calculated using the Kb expression:

Kb = [OH⁻] * [H⁺] / [HA}

[OH⁻] = [H⁺] = x

Kb = x² / (1.63 - x)

Assuming is x <<< 1.63, x is negligible and the denominator = 1.63

x = √(2.19 * 10⁻⁴ x 10⁻¹¹ * 1.63)

x = 3.57 * 10⁻⁴

pOH = -log (3.57 * 10⁻⁴)

pOH = 3.44

pH = 14 - 3.44

pH = 10.56

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The no. Of moles of carbon is found to be 7.5×10⁻⁴.

No. of moles are give by = Given mass/molar mass.

Given mass is 0.009g and the molar mass of carbon atom is 12g.

So, the no. Of moles are given by ,

No. Of moles = 0.009/12

= 0.00075 = 7.5×10⁻⁴mol.

The value of 6.023 x 10²³ is equal to one mole of any substance (Avogadro number). It can be used to quantify the chemical reaction’s by-products. The symbol for the unit is mol.

Carbon element is insoluble in water, diluted acids and bases, as well as organic solvents, carbon is an inert material. It combines with oxygen at high temperatures to generate carbon monoxide or dioxide. Diamond and graphite are two distinct allotropes, crystalline forms of the carbon atom.

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Carlon is modelling the strike slip fault .

Faults are known as displacement or fractures that occurs on Earth's crust arising from cracks as the movement of rocks continuosly slide against  each other. They can be tiny without causing any cracks or very large cause noticeable defects between the rock layers.

A strike slip fault is also known as a Lateral fault zone.

Here, The fault shows how  two blocks of  the earth's crustal plates   undergo a horizontally slip on a  fault plane. This slip can case cracks which extends  deep inside the crust causing continuos wear and tear as they rub on each other.

Most times this  stretches and eventually causes earthquakes

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To know the molarity of carbonic acid when titrated with ammonium hydroxide. We use [tex]M_{1} V_{1} =M_{2} V_{2}[/tex] formula and hence the molarity of carbonic acid is 0.063M.

Titration is an experimental technique in which the molarity of unknown solution is calculated using other solution whose molarity is known. To know the end point we use phenolphthalein as indicator.  

Mathematically,

[tex]M_{1} V_{1} =M_{2} V_{2}[/tex]

where,

[tex]M_{1}[/tex]=Molarity of carbonic acid

[tex]M_{2}[/tex]=Molarity of  ammonium hydroxide

[tex]V_{1}[/tex]=Volume of  carbonic acid

[tex]V_{2}[/tex]=Volume of  ammonium hydroxide

Substituting all values

[tex]M_{1}[/tex]=(0.125×23.8)÷47.00

[tex]M_{1}[/tex]=0.063M

Thus the molarity of  carbonic acid is 0.063M

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Answer:

23.4 milliliters

Explanation:

Note 1: This answer assumes that the volume of CuNO3 is negligible
Note 2: CuNO3 can't be produced in any meaningful quantities and can't be obtained by the average chemist, maybe you meant Cu(NO3)2 instead?

From the definition of molarity, molarity = moles / volume
the number of moles is the number of grams divided by the molar mass, or
2.47 divided by 125.55 which is 0.01967

The M and moles is known so volume can be found.

0.82 = 0.01967 / volume
0.82 * volume = 0.01967
volume = 0.01967 / 0.82 = 0.023988 liters = 23.4 milliliters

Step-by-step explanation:

Assuming a basis of 100 grams

composition of Potassium = 44.2%

composition of potassium = 0.442

mass of potassium = 0.442 x 100g

Mass of potassium= 44.2 grams

mole of potassium = reacting mass / molar mass

Molar mass of potassium = 39.1 gram/ mol

Mole of potassium = 44.2 / 39.1

Mole of potassium = 1.13 moles

mole of potassium chloride + mole of potassium nitrate = mole of potassium

n(KCL) + n(KNO3) = n(k)

since mole (n) = m/M.M

Then we have,

m(KCL)/M.M(KCL) + m(KNO3)/M.M (KNO3) = 1.13

M.M (KCL) = 39.1 + 35.5

M.M (KCL) = 74.6 gram/mol

M.M (KNO3) = 39.1 + 14 + 3(16)

M.M (KNO3) = 39.1 + 14 + 48

M.M (KNO3) = 101.1 gram/mol

Let the mass of KCL be x

Let the mass of KNO3 be y

Assuming the total mass of the mixture is 100g

x + y = 100 ---------- equation 1

x/74.6 + y/101.1 = 1.13 ---- equation 2

From the first equation, make x the subject of the formula

x = 100 - y

100- y / 74.6 + y/101.1 = 1.1.3

1.355(100 - y) + y = 1.13 * 101.1

135.52 - 1.355y + y = 114.243

Collect the like terms

-1.355y - y = 114.243 - 135.52

-0.355y = -21.277

Divide both sides by -0.355

-0.355y/-0.355 = -21.277/-0.355

y = 59.9grams

y is 60 grams approximately

Recall, y is the mass of KNO3

From the first equation

x + y = 100

The bottom of a muddy puddle breaks a ceramic plate Both are only physical changes. Option A.

Breaking a plate is a physical change because no new products are formed during the event. It cannot be called a chemical change because the chemical composition of the splinter is the same as sheet metal. Any physical change that involves a change of state is reversible. Other state changes include evaporative freezing and condensation. Dissolution is also a reversible physical change.

When water is added to a mixture of sand and salt a solution of dissolved salts is formed leaving the sand intact. This is the physical change in recovering salts and sands from solution by filtration and evaporation. Glass breakage is a physical change because the chemical composition of glass does not change when broken. Furthermore, broken glass can be melted back into its original shape.

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The Lewis structure of the carbon tetrabromide would have 4 single bonds to carbon

We know that the Lewis structure of a compound is the kind of structure that shows the symbols of the elements that are found in the compound along side the number of valence electrons that are present.

When we apply the Lewis structure to a molecule, we would see that the symbols of the atoms that can be found in the molecule would be shown as well as the number of valence electrons on the atoms of the elements in the molecule.

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Molarity is a way of expressing the concentration of a solute in a solution, it is expressed with the term M and can be described by the following equation:

Moles of solute = 0.450 mol

Lsolution= Liters of water+Liters of NaCl

We will assume in this case that the volume of NaCl is negligible compared to the volume of water. Therefore, the volume of the solution will be 145.0 mL or 0.1450L

We replace the known data:

Answer: The molarity of the NaCl solution is 3.1M

Answer:

2358

Explanation:

the whole answer is 2358.11

Taking into account definition of percent yield, the percent yield of sodium chloride is 38.11%.

In first place, the balanced reaction is:

HCl + NaOH → NaCl + H₂O

By reaction stoichiometry (that is, the relationship between the amount of reagents and products in a chemical reaction), the following amounts of moles of each compound participate in the reaction:

The molar mass of the compounds is:

Then, by reaction stoichiometry, the following mass quantities of each compound participate in the reaction:

The limiting reagent is one that is consumed first in its entirety, determining the maximum amount of product in the reaction.

To determine the limiting reagent, it is possible to use a simple rule of three as follows: if by stoichiometry 36.45 grams of HCl reacts with 40 grams of NaOH, 2.6 grams of HCl reacts with how much mass of NaOH?

mass of NaOH= (2.6 grams of HCl× 40 grams of NaOH)÷ 36.45 grams of HCl

mass of NaOH= 2.85 grams

But 2.85 grams of NaOH are not available, 2.1 grams are available. Since you have less mass than you need to react with 2.6 grams of HCl, NaOH will be the limiting reagent.

The percent yield is the ratio of the actual return to the theoretical return.

The percent yield is calculated as the experimental yield divided by the theoretical yield multiplied by 100%:

percent yield= (actual yield÷ theoretical yield)×100%

where the theoretical yield is the amount of product acquired through the complete conversion of all reagents in the final product.

Considering the limiting reagent, the following rule of three can be applied: if by reaction stoichiometry 40 grams of NaOH form 58.45 grams of NaCl, 2.1 grams of NaOH form how much mass of NaCl?

mass of NaOH= (2.1 grams of NaOH× 58.45 grams of NaCl)÷ 40 grams of NaOH

mass of NaOH= 3.07 grams

Then, the theoretical yield of NaCl is 3.07 grams.

In this case, you know:

Replacing in the definition of percent yields:

percent yield= (1.17 grams÷ 3.07 grams)×100%

Solving:

percent yield= 38.11%

Finally, the percent yield for the reaction is 38.11%.

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Answer:

62 picometer/millisecond

Explanation:

You multiply the speed value by 1

I need three more brainliest to level up, so if you could mark me as that, that would be great. I hope this helps though!

The balanced equation for the reaction above is: 2Mg(s) + O₂(g) = 2MgO(s).

To balance a chemical reaction or equation, it simply means to make sure the total number of atoms of elements on the reactants side of the equation equals or is the same as the number of atoms in product side.

From the task given above, to balance the equation in the reaction between magnesium and oxygen to give the product, magnesium oxide:

Mg(s) + O₂(g) = MgO(s)

Since there are 2 oxygen atoms in reaction side and 1 oxygen atom at the product side, you'll add 2 to the product (MgO) so we can have the same number of oxygen atoms as the reactant side and complete it by adding 2 also to magnesium in the product side:

2Mg(s) + O₂(g) = 2MgO(s

So therefore, having the same atom numbers in both reactants and products side is the only way to balance chemical equation.

Complete question:

Balance the chemical reaction below:

___Mg(s) + ___O₂(g) ____MgO(s)?

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The enthalpy of the reaction is obtained as -430.22 kJ/mol

The enthalpy change refers to the energy that is lost or gained in the reaction. Let us now look at the standard enthalpies of formation of the reactants and the products.

Standard enthalpy of formation of gaseous  water = -241.82 kJ/mol

Standard  enthalpy of formation of gaseous carbon dioxide = -393.5 kJ/mol

Standard  enthalpy of formation of gaseous methanol = -205.10 kJ/mol

Standard  enthalpy of formation of gaseous oxygen = 0 kJ/mol

Hence;

Using the formula;

Enthalpy of formation of the products - Enthalpy of formation of the reactants

ΔH = [(-393.5 ) + (-241.82)] - [(-205.10) + 0]

ΔH = (-635.32) + 205.10

ΔH = -430.22 kJ/mol

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The molecular equation of the reaction of copper chloride and aqueous silver nitrate:

CuCl₂ (aq)  + 2 AgNO₃ (aq)  →   Cu(NO₃)₂ (aq)  +  2AgCl (s)  

The net ionic equation will be:

2Ag⁺(aq) +  2Cl⁻(aq) → 2AgCl(s)  

The net ionic equation can be described as an equation that represents only those elements, compounds, or ions that directly participated in that particular chemical reaction.

The balanced chemical equation reaction of copper chloride and aqueous silver nitrate:

CuCl₂ (aq)  + 2 AgNO₃ (aq)  →   Cu(NO₃)₂ (aq)  +  2AgCl (s)  

The complete ionic equation for the reaction can be represented as follows:

Cu²⁺(aq) + 2Cl⁻(aq) +  2Ag⁺(aq) + 2NO₃⁻ →  Cu²⁺ (aq) + 2NO₃⁻(aq) + 2AgCl(s)  

In the ionic equation, the copper and nitrate ions appear unchanged on both sides of the equation. When we mix the two solutions, the copper and nitrate ions do not participate in the reaction. So copper and nitrate ions can be eliminated from the ionic equation.

2Ag⁺(aq) +  2Cl⁻(aq) → 2AgCl(s)  

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ANSWER

The mass of glucose in grams is 230 grams

EXPLANATION

Given information

The total volume of the solution = 1.5L

Follow the steps below to find the mass of glucose

Step 1: Convert the volume of the solution from L to mL

According to the standard conversion, 1L is equivalent to 1000mL

Let x represents the volume of the solution in mL

Hence, the volume of the solution in mL is 1500mL

Step 2: Find the mass of the glucose in grams

Hence, the mass of glucose in grams is 229.5 grams

The enthalpy of the reaction is -164 kJ/mol.

We know that the reaction that occurs between the chromium metal and the acid is an exothermic reaction thus there is an increase in the temperature of the system.

Number of moles of the silver nitrate solution is obtained from;

Volume * concentration

500/1000 L * 0.915 M = 0.46 moles

We can now assume that the density of the solution is 1 g/mL hence the mass of the solution is 500g. Let the specific heat capacity of the solution be 4.18 J/Kg/°C.

Then;

H = mcdT

H = Heat lost in the reaction

m = mass of the solution

c = specific heat capacity

dT = temperature change

H = 500 * 4.12 * ( 55.9 - 19.3)

= 75.4 kJ

The heat of reaction = 75.4 kJ/0.46 moles

= -164 kJ/mol

Let us recall that the negative simply means that heat was lost in the reaction.

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A molecule that plays a role in a feedback loop increase the production of one outcome in a cyclic manner.

A feedback loop is a biological phenomenon in which the outcome in the system is required to increase the production for a given molecule, thereby the output converts into the input of the system to produce a given result that maintains across time.

Therefore, we can conclude that a feedback loop is a system in which the input and output are the same in some periods of its functioning.

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The balanced equation is

We need the molar mass of each compound.

• The molar mass of Hg(NO3)2 is 324.7 g/mol.

• The molar mass of Na2Cr2O7 is 261.97 g/mol.

• The molar mass of HgCr2O7 is 416.58 g/mol.

• The molar mass of 2Na(NO3) is 169.99 g/mol.

Then, we find the number of moles of each reactant.

• Moles of Hg(NO3)2 = 24.68g ÷ 324.7 g/mol = 0.076 mol.

• Moles of Na2Cr2O7 = 7.41g ÷ 261.97 g/mol = 0.028 mol.

According to equation 1 mole of Hg(NO3)2 will react with 1 mole of Na2Cr2O7, which means 0.076 mol of Hg(NO3)2 has to react with 0.076 mol Na2Cr2O7, which is not possible because there are not enough moles to get 0.076 of Na2Cr2O7 in the reaction. Hence, Na2Cr2O7 is the limiting reactant and Hg(NO3)2 is the excess reactant.

Then, subtract the number of moles to obtain the excess:

The remaining moles from Hg(NO3)2 are: 0.076mol - 0.028 = 0.048 mol.

Therefore, the remaining excess reactant is 0.048 moles.

But, we need to transform it to grams using the molar mass of Hg(NO3)2.

Therefore, the remaining mass of Hg(NO3)2. is 15.59 grams.

Taking into account the definition of pH and pOH, you get:

a) the pH of a solution of HCl is 2.6 and its mass is 0.045575 grams.

b) the pH of a solution of Ca(OH)₂ is 12.61 and its mass is 2.9636 grams.

pH is a measure of acidity or alkalinity that indicates the amount of hydrogen ions present in a solution or substance.

The pH is defined as the negative base 10 logarithm of the activity of hydrogen ions, that is, the concentration of hydrogen ions or H₃O⁺:

pH= - log [H⁺]

pOH is a measure of hydroxyl ions in a solution and is expressed as the logarithm of the concentration of OH⁻ ions, with the sign changed:

pOH= - log [OH⁻]

The following relationship can be established between pH and pOH:

pOH + pH= 14

An acid and a base are strong when they are completely ionized, that is, in the process of ionization they are completely transformed into cations or positive ions and anions or negative ions.

Then the initial concentration of the acid or base will be equal to the concentration for the anion and the cation.

Molar concentration or molarity is a measure of the concentration of a solute in a solution and indicates the number of moles of solute that are dissolved in a given volume.

The molarity of a solution is calculated by:

molarity= number of moles÷ volume

Molarity is expressed in units moles/L.

The molar mass of substance is a property defined as its mass per unit quantity of substance, in other words, molar mass is the amount of mass that a substance contains in one mole.

You know that:

HCl is a strong acid. Then [HCl]= [H⁺]= 0.0025 M.

The pH of the solution can be calculated as:

pH= - log 0.0025 M

Solving:

pH= 2.6

The pH in this case is 2.6.

The amount of moles of HCl is calculated as:

number of moles= [HCl]× Volume

number of moles= 0.0025 M× 0.500 L

number of moles= 0.00125 moles

Finally, the mass of the solution of HCl is calculated as:

mass= number of moles× molar mass

mass= 0.00125 moles× 36.46 g/mole

mass= 0.045575 grams

Finally, the mass of the solution is 0.045575 grams.

You know that:

Ca(OH)₂ is a strong base. Then [Ca(OH)₂]= 0.02 M and [OH⁻]=2×[Ca(OH)₂]= 0.04 M since the compound forms 2 OH⁻.

The pOH of the solution can be calculated as:

pOH= - log 0.04

Solving:

pOH= 1.39

Replacing in the relationship between pH and pOH:

pH + 1.39= 14

Solving:

pH= 14 - 1.39

pH= 12.61

The pH in this case is 12.61.

The amount of moles of Ca(OH)₂ is calculated as:

number of moles= [Ca(OH)₂]× Volume

number of moles= 0.02 M× 2 L

number of moles= 0.04 moles

Finally, the mass of the solution of Ca(OH)₂ is calculated as:

mass= number of moles× molar mass

mass= 0.04 moles× 74.09 g/mole

mass= 2.9636 grams

Finally, the mass of the solution is 2.9636 grams.

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Armondo could test how curves in a river affect the speed of the river as the speed of the water outside of a bend increases as a river rounds the bend. The water's velocity, however, diminishes as it approaches the interior of the curve.

A fantastic illustration of how water can alter the contour of the land is a meandering river. A river seldom turns when it is bordered by sheer rock, but it will do so when it opens up in broad valleys. Water will flow more swiftly and destroy the ground faster outside the river. Over time, it will curve too much and slow down.

To simulate a meandering river, use a stream table. The speed of the water outside of a bend increases as a river rounds the bend. The water's velocity, however, diminishes as it approaches the interior of the curve. A bar of deposited silt, like this one, is created as a result of the reduction in velocity.

The velocity of a river is the rate at which water flows through its course. Numerous elements, such as the channel's form, the slope's grade, the amount of water carried by the river, and the amount of friction brought on by jagged edges in the riverbed, all affect a river's speed.

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Explanation:

Because during the phase transformation the pressure inside the closed container remains the same and that's a fact ay

Answer:

- The name for the potassium oxide's structure is ionic.

Properties:

- High melting point.

- Soluble in water.

Explanation:

- The ionic structure it is formed by a cation (atom with positive charge) and an anion (atom with negative charge). In this case, potassium is the cation and the oxigen is the anion.

- Since potassium oxide is an ionic compound, it has a high melting point, because of the strong bonds. Also, it is soluble in polar solvents, like water, because its ions generate polarity in the molecule.

The pH of a solution that is 0.67 M in sodium fluoride and 0.43 M in hydrofluoric acid is 0.37

The pH of a solution is the negative logarithm of the hydrogen ion concentration of the solution.

pH = - log [H⁺]

The pH of the given solution is calculated as follows:

Concentration of the sodium fluoride solution = 0.67 M

Hydrogen concentration = 0
The concentration of the hydrofluoric acid solution = 0.43 M

Hydrogen concentration = 0.43 M

pH = - log(0.43)

pH = 0.37

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1)

Na3PO4 + H2SO4 => Na2SO4 + H3PO4

We must have the same number of atoms on both sides.

We start with Na,

2 Na3PO4 + H2SO4 =>3 Na2SO4 + H3PO4 (6 Na on both sides)

Then we proceed with P,

2 Na3PO4 + H2SO4 =>3 Na2SO4 +2 H3PO4 (2 P on both sides)

After that, we continue with S,

2 Na3PO4 + 3 H2SO4 =>3 Na2SO4 +2 H3PO4 (3 S)

The number of H and O are solved.

Answer: 2 Na3PO4 + 3 H2SO4 =>3 Na2SO4 +2 H3PO4

Answer:

For every action, there is opposite and equal reaction

The amount of heat energy needed to increase a substance's temperature by 1°C per unit mass is known as its specific heat capacity (or 1K). joule per kilogram per kelvin is the SI unit (Jkg-1K-1).

so,

805,560 Joules heat energy is needed to raise the temperature  from 23 °C to 191 °C.

Use the formula:

Q = cMΔT

where

Q = heat energy needed for that material to get desired temperature change (in Joules)

M = mass (in grams) so you have to convert from kilograms.

c = specific heat constant for the material being heated [in /(grams oC)]

ΔT = change in temperature (in oC)

Q = (1.75)(2.74 x 1000)(191 - 23) = (1.75)(2740)(168) = 805,560 Joules

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Q = cMΔT

where

Q is the amount of heat energy required to change the material's temperature.

You must convert from kilograms since M is mass (in grams).

c = the material's specific heat constant [in grams per degree Celsius]

T stands for temperature change (in oC)

Q is equal to (1.75 x 2.17 x 1000) (191 - 23) = (1.75 x 2170 x 168) = 637,980 Joules.

What does "specific heat capacity" mean?

In thermodynamics, a substance's specific heat capacity, commonly referred to as massic heat capacity, is calculated by dividing its heat capacity by its mass in a sample.

particular heat capacity's mathematical formula?

Delta T = Q=mc

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The law the scientist used to predict that the product of the reaction would be 15.9 grams of copper sulfide is law of conservation of matter

The law of conservation of matter states that matter can neither be created nor destroyed during a chemical reaction but can be transferred from one form to another.

The above law suggest that the total mass of reactants must equal to the total mass of the product obtained in a chemical reaction.

With the above information, we can obtain the mass of Cu₂S as follow:

2Cu + S → Cu₂S

Mass of Cu + mass of S = Mass of Cu₂S

12.7 + 3.2 = Mass of Cu₂S

Mass of Cu₂S = 15.9 grams

Thus, from the above illustrations, we can conclude that the law the scientist used was the law of conservation of matter

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