In a mixture of argon and hydrogen, occupying a volume of 1.18 l at 894.6 mmhg and 44.1oc, it is found that the total mass of the sample is 1.25 g. what is the partial pressure of argon?

Any salt, even though it reacts with water, will precipitate out completely when the water is completely evaporated.  If you start with 50 grams of salt, you will end up with 50 grams of salt.

100 centigrams over one gram  is a valid conversion factor. The answer is OPTION D.

A valid conversion factor is a ratio of two equivalent quantities expressed in different units, and it allows you to convert between those units. In this case, centigrams (cg) and grams (g) are both units of mass, but the conversion factor should be based on their relationship as defined in the metric system. In the metric system, there are 100 centigrams in one gram.

This means that one gram is equivalent to 100 centigrams. To convert from grams to centigrams, you would multiply the quantity in grams by 100, and to convert from centigrams to grams, you would divide the quantity in centigrams by 100. The correct conversion factor is a fundamental concept in metric system conversions and scientific measurements.

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1) The chemical symbol for the atom is selenium.

2) The total number of electrons is 16 electrons in the selenium atom.

3) There are 2 5s electrons are in the atom.

The electron configuration [Kr][tex]5s^24d^{10}5p^4[/tex] corresponds to the chemical element Selenium (Se).

1. Chemical Symbol: The chemical symbol for the atom is Se, representing the element selenium.

2. Number of Electrons: To determine the number of electrons in the atom, you need to add up the electron count in each orbital. In this case, the electron configuration tells us that there are:

- 2 electrons in the 5s orbital.

- 10 electrons in the 4d orbital.

- 4 electrons in the 5p orbital.

So, the total number of electrons is 2 + 10 + 4 = 16 electrons in the selenium atom.

3. Number of 5s Electrons: The electron configuration specifies that there are 2 electrons in the 5s orbital.

In summary, the chemical symbol for the atom is Se, it has 16 electrons, and there are 2 electrons in the 5s orbital of the selenium atom. This electron configuration provides insight into the distribution of electrons in the selenium atom, which is crucial for understanding its chemical behavior and reactivity.

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B rises sharply on the right

The pattern which serves as a characteristic of a graph of exponential growth is that it B rises sharply on the right .

Exponential growth serves as a consistent growth rate that brings about rapid increase in growth as total growth numbers increase.

It do takes place when there is an instantaneous rate of change of a quantity with respect to time.

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Methylene blue indicates the presence of oxidizing agents because it is oxidized itself by these compounds. When electrons are stripped from methylene blue, the resulting molecule imparts a blue color to the solution--giving a clear sign of a chemical change.

Methylene blue appears blue because of its unique molecular structure with an extended system of conjugated pi bonds, which absorbs certain wavelengths of light in the non-blue spectrum. In its oxidized state, it is blue, and in its reduced form, it is colorless.

Methylene blue shows a blue color due to its unique chemical structure. It absorbs certain wavelengths of light within the blue region of the visible spectrum due to its extended system of conjugated pi bonds, i.e., alternate single and double bonds in its molecular structure. Methylene blue does not absorb blue light, but reflects it, making the compound appear blue to our eyes.

Additionally, Methylene blue is known for its reduction-oxidation properties. In an oxidized state, it is blue, while its reduced form is colorless. This means that the molecule can change its color based on whether it is gaining or losing electrons, a property that is utilized in many biological and research applications, including staining cells for microscope viewing and acting as an antidote for certain types of poisonings, like rotenone poisoning.

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In a chemical equation, the arrow  

A. can be read as "yields" or "makes."  

B. always points toward the products.  

C. separates the products and reactants.  

D. all of these

all of these options are right.

Answer:  the answer is all of these

Explanation:

Answer: [tex]Cu(NO_3)_2[/tex] solution has blue color and [tex]Ni(NO_3)_2[/tex] solution has bright green color.

Explanation:

[tex]Cu(NO_3)_2(aq)\rightarrow Cu^{2+}(aq)(blue)+ NO_{3}^{1-}(aq)[/tex]

[tex]Cu(NO_3)2[/tex] in its aqueous solution gives blue color solution. Copper being transition metal and gives characteristic color in their in aqueous solution.

[tex]Ni(NO_3)_2(aq)\rightarrow Ni^{2+}(aq)(green)+ NO_{3}^{1-}(aq)[/tex]

[tex]Ni(NO_3)2[/tex] in its aqueous solution gives bright green color solution. Nickel is also a transition metal and gives characteristic color in their in aqueous solution.

Cu(NO3)2 solution shows a deep blue color due to the Cu²⁺ ions it contains, whereas Ni(NO3)2 solution generally appears greenish due to the Ni²⁺ ions. You can distinguish these solutions by their colors.

You can distinguish between a Cu(NO3)2 (copper(II) nitrate) solution and a Ni(NO3)2 (nickel(II) nitrate) solution by color. Specifically, Cu(NO3)2 solutions are typically characterized by a deep blue color due to the Cu²⁺ ions it contains.

On the other hand, Ni(NO3)2 solutions generally appear greenish, owed to the characteristic color of Ni²⁺ ions. Figures 19.40 and 18.36 show this difference -- while the copper nitrate solution shows a deep blue color, a nickel nitrate solution would appear more greenish.

Thus, by observing the color of the solutions, it is possible to distinguish between them based on the characteristic color patterns of their constituent ions.

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Answer:

0.640 Torr; 1.28 Torr  

Step-by-step explanation:

According to Raoult's Law,

(1) p₁ = χ₁p₁°,  

where p₁ is the solvent

χ₁ + χ₂ = 1                        Subtract χ₁ from each side

      χ₂ = 1 – k₁                          Substitute in (1)

(2)    p₁ = (1 – χ₂)p₁°    Remove parentheses

       p₁ = p₁°- χ₂p₁°      Subtract p₁° from each side

p₁ - p₁° = -χ₂p₁°              Multiply each side by -1

     Δp =   χ₂p₁°

Δp is the vapour pressure lowering.

If the solute is an electrolyte, we must insert the van't Hoff i factor.

ΔP = iχ₂P₁°

===============

(1) Calculate χ₂ for each solution

Water:

1000 g = 1000 × 1/18.02

          = 55.49 mol

      χ₂ = 2.10/(2.10 + 55.49)

          = 2.10/57.59

          = 0.036 46

===============

(2) Calculate the vapour pressure lowering

(a) Sucrose

   i = 1

ΔP = 1 × 0.036 46 × 17.54

ΔP = 0.640 Torr

=====

(b) NaCl

   i = 2

ΔP = 2 × 0.640

ΔP = 1.28 torr

Answer:

The volume of 3.25 grams of ammonia is 4.28 L

Explanation:

Step 1: Data given

Mass of ammonia = 3.25 grams

Molar mass of ammonia = 17.03 g/mol

Step 2: Calculate moles ammonia

Moles NH3 = mass NH3 / molar mass NH3

Moles NH3 = 3.25 grams / 17.03 g/mol

Moles NH3 = 0.191 moles

Step 3: Calculate volume of NH3

1 mol = 22.4 L

0.191 moles = 22.4 * 0.191 = 4.28 L

The volume of 3.25 grams of ammonia is 4.28 L

To find the volume of 3.25 g of ammonia, assuming an 8% solution with water-like density, we calculate the moles of ammonia and use the molarity to estimate the volume, which is approximately 40.7 mL.

To calculate the number of liters of ammonia in 3.25 g, we need to consider the density of ammonia. However, the initial question seems incomplete as it does not provide the concentration or density of ammonia directly. Instead, we are just provided a percentage which is typically used for solutions.

If we assume a solution of ammonia with a density similar to water, the number of liters can be estimated using the analytical concentration of an 8% ammonia by weight solution. Given this solution, ammonia has a concentration of 4.7 M (mol/L, assuming 1 L weighs 1000 g and 80 g of ammonia corresponds to 80 / 17 = 4.705882353 mol/L).

The number of moles of ammonia in 3.25 g can be calculated by dividing the mass by the molar mass of ammonia (17 g/mol):

n = mass / molar mass = 3.25 g / 17 g/mol = 0.1912 mol

Now, using the molarity (M), which is moles of solute per liter of solution (mol/L), we can find the volume V:

V = n / M = 0.1912 mol / 4.7 mol/L = 0.0407 L or 40.7 mL

Therefore, 3.25 g of an 8% ammonia solution corresponds to approximately 40.7 mL.

The most toxic substance that accumulates in aquarium is ammonia

It is highly toxic to fish present in aquarium

This ammonia is produced due to accumulation of fish or plant waste or unused food in aquarium.

Answer:

b. Extraction with a solution of sodium hydrogen carbonate, separating the layers, followed by drying and evaporating the organic layer.

Step-by-step explanation:

The ether solution contains your product, benzaldehyde, and some starting material, benzoic acid, the purification steps are:

a. is wrong. Extraction with HCl will not remove much of the benzoic acid.

c. is wrong. If you evaporate the organic layer, you will have a mixture of benzaldehyde and benzoic acid.

d. is wrong. If you work with the aqueous layer, you will end up with benzoic acid,

Answer:

C) The half life of carbon-14 is about 5700 years and is too short to date rocks.  

Step-by-step explanation:

The practical limit for carbon dating is about nine half-lives (50 000 yr).

At that point, the amount of carbon remaining has dropped to about 0.2 % of the original amount.

The experimental uncertainties involved become so large that carbon dating is no longer reliable.

Most rocks hundreds of millions or even billions of years old.

Any radioactive carbon would have long since decayed to unmeasurable levels.

A) is wrong. Many rocks contain carbon, but they are so old that the amount of radioactive carbon has dropped below measurables.

B) is wrong. The half-life of carbon is too short to use for dating rocks.

D) is wrong. About 20 % of the carbon in rocks comes from living things that were embedded in layers of mud.

===============

Uranium-238 and lead-206 have half-lives of 4.5 × 10⁹ yr, which is about the age of the Earth.

Even the oldest rocks would still have half of their radioactivity, and younger rocks would have more.

Thus, U-238 and Pb-206 are ideal isotopes for measuring the ages of rocks.

1. The metamorphic rocks are produced when the parent or the pre-existing rocks (whether sedimentary, igneous, or even metamorphic) are changed by pressure, heat, and the chemical activity of the fluids.  

When the prime changing factor is heat, generally due to direct contact, it may go through fundamental modification in recrystallization and texture is known as contact metamorphism. While regional metamorphism takes place when the minerals and texture of the rock are modified by pressure and heat.  

Metamorphic rocks form when heat and pressure transform existing rocks through contact or regional metamorphism. The volcanoes northwest of the Big Island of Hawaii are no longer erupting because they have moved away from the hotspot. To locate an earthquake's epicenter, data from a minimum of three seismic stations is required.

1). Metamorphic rocks are formed when existing rocks are transformed by heat and pressure. This process can occur through two main types of metamorphism: contact metamorphism and regional metamorphism.

2). Volcanoes on Hawaiian Islands:

The volcanoes on the Hawaiian islands northwest of the Big Island of Hawaii are no longer erupting because they have moved away from the hotspot in the Earth's mantle that supplies magma. As the Pacific Plate moves northwestward, the older volcanoes are carried away from the hotspot, becoming dormant.

3). Boiling Water:

When explaining how a pot of water boils, three terms are essential: radiation, conduction, and convection.

4). Finding Earthquake Epicenter:

A minimum of three seismic stations is needed to find the epicenter of an earthquake due to the process called triangulation. Each station records the time it takes for seismic waves to reach them, and by plotting circles with the quake's arrival time at each station, the intersection point of the three circles pinpoints the epicenter.

Answer:

A. R represents chemical energy; P represents thermal energy.

Step-by-step explanation:

The molecules in the gas contain chemical energy (R).

When the gas burns, the chemical energy is released as heat, or thermal energy (P).

Answer:

A. R represents chemical energy; P represents thermal energy.

Explanation:

The new volume  temperature is  = 109.9 K

  calculation

The new volume temperature  is calculated  using Charles law  equation

That is V₁/T₁ =V₂/T₂

where;

V₁ = 4.00 L

T₁ = 293 k

V₂ = 1.5 L

T₂ = ?

make  T₂ the subject of the formula

T₂= V₂T₁/V₁

T₂  = {(1.5 L×  293 k) / 4.00 L} =109.9 K

2 H-H + O=O → 2 H-O-H

There are two moles of H-H bonds and one mole of O=O bonds in one mole of reactants. All of them will break in the reaction. That will absorb

Each mole of the reaction will form two moles of water molecules. Each mole of H₂O molecules have two moles O-H bonds. Two moles of the molecule will have four moles of O-H bonds. Forming all those bond will release

Heat of the reaction:

[tex]\Delta H_{\text{rxn}}[/tex] is negative. As a result, the reaction is exothermic.

In the late 1800's, experiments using cathode ray tubes led to the discovery of the;

Electron(s)

It was founded that many different metals release cathode rays, and that cathode rays were made of electrons, very small negatively charged particles.

Antacid generally contains sodium bicarbonate in it.

sodium bicarbonate is a base

Now if we add ant acid in water there will be small amount of effervescence in the glass of water.

However if we add the same ant acid in sprite then there will be large amount of uncontrolled effervescence in the glass.

so we can easily distinguish the two types of glass content.

The  half reaction that occur  at the anode is

Zn (s)→ Zn²⁺ (aq) +  2e⁻

Explanation

Answer: The half reaction occurring at anode is [tex]Zn(s)\rightarrow Zn^{2+}(aq.)+2e^-[/tex]

Explanation:

In a chemical cell, substance getting oxidized always act as anode and the one getting reduced always act as cathode.

Oxidation reaction is defined as the reaction in which an atom looses its electrons. Here, oxidation state of the atom increases.

[tex]X\rightarrow X^{n+}+ne^-[/tex]

Reduction reaction is defined as the reaction in which an atom gains electrons. Here, the oxidation state of the atom decreases.

[tex]X^{n+}+ne^-\rightarrow X[/tex]

For the given chemical cell reaction:

[tex]Zn(s)+2Eu(NO_3)_3(aq.)\rightarrow Zn(NO_3)_2(aq.)+2Eu(NO_3)_2(aq.)[/tex]

Oxidation half reaction (anode):  [tex]Zn(s)\rightarrow Zn^{2+}(aq.)+2e^-[/tex]

Reduction half reaction (cathode):  [tex]Eu^{3+}(aq.)+e^-\rightarrow Eu^{2+}(aq.)[/tex]    ( × 2 )

Here, zinc is loosing electrons and is getting oxidized and europium is gaining electrons and loosing electrons.

Hence, the half reaction occurring at anode is [tex]Zn(s)\rightarrow Zn^{2+}(aq.)+2e^-[/tex]

Answer : The concentration can be expressed as, 1.99 M, or 15.1(m/m)%, or 18(m/v)%

Solution : Given,

Volume of solution = 0.5 L = 500 ml        (1 L = 1000 ml)

Mass of solution = 596 g

Mass of oxalic acid, (solute) = 90 g

Molar mass of oxalic acid = 90.03 g/mole

First we have to calculate the concentration in terms of M(molarity).

Molarity : Molarity is defined as the number of moles of solute present in one liter of solution.

Formula used : [tex]M=\frac{w_{solute}}{M_{solute}\times V_s}[/tex]

where,

M = molarity of solution

[tex]w_{solute}[/tex] = mass of solute(oxalic acid)

[tex]M_{solute}[/tex] = molar mass of solute(oxalic acid)

[tex]V_s[/tex] = volume of solution(in liters)

Now put all the given values in this formula, we get

[tex]M=\frac{90g}{90.03g/mole\times 0.5L}=1.99mole/L=1.99M[/tex]

Now we have to calculate the concentration in terms of (m/m)%

(m/m)% : It is defined as the mass of solute present in mass of solution in grams.

Formula used : [tex](m/m)\%=\frac{w_{solute}}{w_s}\times 100[/tex]

where,

[tex]w_s[/tex] = mass of solution

[tex](m/m)\%=\frac{90g}{596g}\times 100=15.1%[/tex]

Now we have to calculate the concentration in terms of (m/v)%

(m/v)% : It is defined as the mass of solute present in one milliliter of solution.

Formula used : [tex](m/v)\%=\frac{w_{solute}}{V_s}\times 100[/tex]

where,

[tex]w_s[/tex] = mass of solution

[tex](m/m)\%=\frac{90g}{500ml}\times 100=18%[/tex]

Answer is: B. Energy transfer would occur between the copper bars and the surroundings.

Closed system is a physical system that does not allow transfer of mass and energy in or out of the system.

Open system is a physical system that does allow transfer of mass and energy in or out of the system, have input and output flows.

Thermal conductuction is the transfer of heat through physical contact. Thermal conduction is the transfer of heat by microscopic collisions of particles.

Heat spontaneously flows from a hotter to a colder body.

Answer: The correct answer is option B.

Explanation:

Electronic Configuration of Group VII-A : [tex]ns^2np^5[/tex]

This group require 1 electron to attain stable electronic configuration.

Electronic configuration of Group I-A : [tex]ns^1[/tex]

This group will loose 1 electron to attain stable electronic configuration.

So, there will be complete transfer of electron from Group VII-A to Group I-A and hence, will form ionic bond between them.

Hence, the correct option is B.

The correct answer is B. hypothesis is falsifiable, but theory has been proven to be correct. A falsifiable thing is something that can be proved as false, also the hypothesis is an explanation that is suggested after an observation process. On the other hand, a theory is a more reliable source because it is verified, checked and proved after certain events that have evidence to certify.

The amount of moles in 3.34x10^34 formula units of Cu(OH)2 is calculated by dividing the number of formula units by Avogadro's number (6.022 x 10^23 formula units/mol). The resulting value is approximately 5.55x10^10 moles of Cu(OH)2.

To calculate moles from a given number of formula units, we use Avogadro's number: 6.022 x 1023. This number tells us that there are 6.022 x 1023 formula units in one mole of any substance. Therefore, if we have 3.34 x 1034 formula units of Cu(OH)2, we divide this number by Avogadro's number to find the amount in moles.

Here's the calculation:
Number of Moles = 3.34x1034 formula units / 6.022 x 1023 formula units/mol = 5.55x1010 moles of Cu(OH)2

The use of Avogadro's number in this context demonstrates the direct relationship between moles and formula units in a substance, an important concept in chemistry.

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You can determine the number of moles from the number of formula units by dividing the number of formula units by Avogadro's number (6.022 x 10^23). Applying this to the problem, the number of moles in 3.34 x 10^34 formula units of Cu(OH)2 is about 5.54 x 10^10.

The chemistry concept at work here is that 1 mole of any substance contains 6.022 x 10^23 entities of that substance (Avogadro's number). This is true whether these entities are atoms, molecules, ions, electrons, or other particles. The term 'formula units' is used because copper hydroxide (Cu(OH)2) consists of multiple atoms grouped together. In this case, you're being asked the amount of moles in 3.34x10^34 formula units of Cu(OH)2.

Since 1 mole contains 6.022 x 10^23 formula units, you can calculate the number of moles by using the formula:

Number of moles = Number of formula units / Avogadro's number

Substituting the numbers into this formula gives:

Number of moles = 3.34 x 10^34 / 6.022 x 10^23

So, the number of moles in 3.34 x 10^34 formula units of Cu(OH)2 is about 5.54 x 10^10.

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Answer :

Part 1 : conversion factor required for 30%(m/m) NaCl solution.

30%(m/m) NaCl solution that means 30 grams of NaCl is present in 100 gram of solution.

Conversion factor : [tex]30\%\text{ of NaCl solution}=\frac{30\text{ g of NaCl}}{100\text{ g of solution}}[/tex]

Part 2 : conversion factor required for 8%(v/v) ethanol solution.

8%(v/v) ethanol solution that means 8 ml of ethanol is present in 100 ml of solution.

Conversion factor : [tex]8\%\text{ of ethanol solution}=\frac{8\text{ ml of ethanol}}{100\text{ ml of solution}}[/tex]

Part 3 : conversion factor required for 14%(m/v) fructose solution.

14%(m/v) fructose solution that means 14 grams of fructose is present in 100 ml of solution.

Conversion factor : [tex]14\%\text{ of fructose solution}=\frac{14\text{ g of fructose}}{100\text{ ml of solution}}[/tex]

Part 4 : conversion factor required for 5.0 M HBr solution.

'M' represent the 'molarity' which is defined as the number of moles of solute present in one liter of solution.

5.0 M HBr solution that means 5 moles of HBr is present in 1 liter of solution.

Conversion factor : [tex]5.0M\text{ HBr solution}=\frac{5\text{ moles of HBr}}{1\text{ L of solution}}[/tex]

The answer is; It is salt because it is formed by the reaction of an acid and a base.

Salt is composed of cations and anions (with a net charge of 0) joined together by ionic bonds attributed to their complementary charges. NaOH is an alkali salt because it forms an alkaline solution when dissolved in water – because it dissociates hydroxide ions.  

Answer:

the answer is B for short

Explanation:

:)

 The volume  (in liters)  of CO₂  that can  be consumed at STP by 435 g Na₂O₂  is  125 L of Co₂

calculation

2Na₂O₂(s)  +2 CO₂ (g)→  2 Na₂CO₃(s)  + O₂(g)

Step 1 : find the moles  of Na₂O₂

moles = mass÷  molar mass

from periodic table the  molar mass  of Na₂O₂ = (23 x2) +( 16 x2) = 78 g/mol

 moles= 435 g÷ 78 g/mol = 5.58 moles

Step 2: use the mole ratio to determine the moles of CO₂

from given equation  Na₂O₂ : CO₂ =2 :2 =1:1

Therefore the  moles of CO₂  is also = 5.58 moles

Step 3: find the volume  of CO₂  at STP

that is at STP      1  mole of a gas = 22.4 L

                          5.58 moles = ? l

by cross multiplication

= (5.58 moles x 22.4 L) / 1 mole = 125 L

435 g of Sodium peroxide (Na2O2) can consume about 125 liters of carbon dioxide (CO2) at Standard Temperature and Pressure (STP).

The question requires us to determine the volume of CO2 that can be consumed by 435 g of Sodium peroxide (Na2O2) at Standard Temperature and Pressure (STP).

Molar mass of Na2O2 = 2(23) + 2(16) = 78 g/mol. So, 435 g of Na2O2 = 435/78 = 5.58 mol.

From the balanced chemical equation, we know that 2 mol of Na2O2 react with 2 mol of CO2. Thus, 5.58 mol of Na2O2 will react with 5.58 mol of CO2.

At STP, 1 mol of any gas occupies 22.4 liters. Therefore, 5.58 mol of CO2 will occupy 5.58 * 22.4 = 124.99 L. So, 435 g of Na2O2 can consume about 125 L of CO2 at STP.

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Answer : Formation of yellow precipitate is the physical evidence that there has been a chemical reaction.

Explanation :

A chemical reaction happens when 2 or more substances chemically react with each other.

There are 4 evidences indicating that a chemical reaction has occurred which are mentioned below.

1. Change in color : On mixing, the reaction mixture can change color indicating that a chemical change may have occurred.

2. Formation of precipitate : A reaction in which a solid is formed on mixing 2 aqueous solutions is called as precipitation reaction. Here, the formation of solid indicates a chemical change.

ex. [tex]AgNO_{3} (aq) + NaCl (aq) \rightarrow AgCl (s) + NaNO_{3} (aq)[/tex]

In above reaction, on mixing the solutions, a white precipitate of AgCl is formed which indicates a chemical change.

3. Evolution of gas : A chemical change also occurs when a gas is evolved on mixing 2 substances.

ex. [tex]2HCl (aq) + Na_{2}CO_{3} (aq) \rightarrow 2NaCl (aq) + H_{2}O (l) + CO_{2} (g)[/tex]

In above reaction, CO2 gas is evolved and bubbles can be seen in the form of effervescence.

4. Change in temperature : Certain chemical reactions absorb or evolve heat. When a chemical reaction evolves heat, the temperature of the final reaction mixture increases and when it absorbs heat, the temperature decreases. This increase and decrease in temperature indicates a chemical change.

ex.  [tex]HCl (aq) + NaOH (aq) \rightarrow NaCl(aq) + H_{2}O (l)[/tex]

In above reaction, the final mixture becomes hot as the reaction releases heat. ( Exothermic)

Change in odor also indicates a chemical change.

For the given reaction, a yellow precipitate of PbI2 is getting formed.

Therefore formation of this precipitate is the physical evidence that there has been a chemical reaction.

Answer:

precipitate formation occurs

Explanation:

did usa test prep

equation Fe3O4=Fe+CO2 is an impossible reaction