As part of a science experiment, Jose did a test for starch on a slice of apple and a slice of potato. The yellow-orange iodine solution stayed the same color when it was put on the apple, but it became black on the potato. Why did the iodine solution change color on the potato? A. The iodine evaporated into a gas. B. The iodine mixed with the colors of the potato so it looked black. C. The iodine burned the potato and turned it to ash. D. The iodine reacted with the potato to form a new substance.

Answers

Answer 1
D. I know this because i did the project 3 weeks ago.
Answer 2

Answer:

The iodine reacted with the potato to form a new substance.

Explanation:


Related Questions

A piece of copper at 10 °C is dropped into a glass of water at 35 °C. Which statement is correct?

A. Heat will flow from the copper to the water in the glass until both reach the same temperature.

B. Heat will flow from the water in the glass to the copper until both reach the same temperature.

C. The final temperature of the water in the glass and the copper will be 10 °C.

D. The final temperature of the water in the glass and the copper will be 35 °C.

Answers

I say B. Why? because the heat will keep on moving in molecules until it reaches same temperature

Answer:

The correct answer is option B, that is, heat will flow from the water in the glass to the copper until both reach the same temperature.

Explanation:

Let us see a perfectly thermal insulation system with a glass of water at higher temperatures and a piece of copper at a lower temperature, and when both encounters each other than water will lose some of the heat and that heat will be gained by the copper. The procedure will take place until and unless both attain a similar temperature. After attaining a similar temperature, there will be no change in temperature or heat between the two.  The change in heat is a function of temperature difference.

HQ5.49 Use standard enthalpies of formation to calculate the standard enthalpy of reaction for the following reaction: 2 H 2 ​ S(g) + 3 O 2 ​ (g) → 2 H 2 ​ O(l) + 2 SO 2 ​ (g) ΔH ∘ rxn ​

Answers

Answer is: the standard enthalpy of reaction is -1124,2 kJ/mol.
ΔHf(H₂S) = -20.5 kJ/mol
ΔHf(O₂)=0 kJ/mol.
ΔHf(H₂O) = -285.8 kJ/mol.
ΔHf(SO₂) = -296.8 kJ/mol.
ΔHrxn = ∑ΔHf (products of reaction) - ∑ΔHf (reactants).
ΔHrxn - enthalpy change of chemical reaction.
ΔHf - enthalpy of formation of reactants or products.
ΔHrxn = (2 · (-285,8) + 2 · (-296,8)) - (2 · (-20,5)) · kJ/mol.
ΔHrxn = -1124,2 kJ/mol.

Earth's path around the sun is _____.


a) eliptical
b) circular
c)random
d) triangular

Answers

The answer is A

Hope this helps

~ Jordan ~

Through which of the following processes is carbon directly transferred between living organisms and the environment?

Answers

Answer:

The answer is carbon cycle.

Explanation:

The carbon cycle is an important process for living organisms. As plants prepare their food through photosynthesis and is also an important source of fossil fuels for human activities.

Therefore carbon atoms are regenerated again and again in the carbon cycle process. This recycling process takes place between livings and nonliving things in the environment and also within the earth biosphere.

Abundance supply of carbon is necessary to carry out the biological processes. The entire carbon cycle is actually made up of sourced and sinks elements.

Why are sound recordings needed to preserve sound information

Answers

Original instantaneous sound recordings are in need of special preservation care. Today many of these historical sound recordings are reaching the end of their life span.
I am not sure if you have any answer choices or not, but I will just try to give my own answer. Sound recordings are needed to preserve important info such as historical events. This is because audio is what I like to call "key evidence" or just proof that something happened. An example would be Martin Luther's speech. Someone could say that he said something completely different from what he actually said, and without a recording, we wouldn't actually know. Another reason for sound recordings would be songs and music. Without sound recordings, we wouldn't have songs to listen to all day and night. We would have to go to concerts in order to hear music. I am not sure if any of this helped or not. If it did, please let me know. If it did not, then I am truly sorry, for at this exact moment in time, I can think of no other answers for this question.

An electromagnetic wave that has a lower frequency than infrared radiation will have ____ than the infrared radiation. longer wavelength and higher energy longer wavelength and lower energy shorter wavelength and higher energy shorter wavelength and lower energy

Answers

Answer: longer wavelength and lower energy.

Explanation:

1) The wavelength is inversely related to the frequency. So, an electromagnetic wave with lower frequency will have longer wavelength.

This is the formula for electromagnetic waves:

λ = c / ν

where λ is the wavelength, c is the speed of light, and ν is the frequency.

2) Energy is directly related to the frequency.

This is the formula E = hν,

where E is the energy, h is Planck constant, and ν is the frequency.

So, the lower the frequency the lower the energy.

3) Conclusion:
An electromagnetic wave that has a lower frequency than infrared radiation will have longer wavelength and lower energy than the infrared radiation

The answer is longer wavelength and lower energy.

How hot or cold is Mercury

Answers

in the day it's -279 Fahrenheit ( -173 Celsius) and at night it's 801 Fahrenheit ( 427 Celsius)   
Well it all depends on the time of day, where it varies from very cold
(-279F or -173C)at night to very hot (800F or 430C) during the day. This is due to the lack of atmosphere this planet has. And although it is the closest planet to the sun it is only the 2nd hottest planet

ll of the following could be considered reconstruction except :

A. scientists assume an area was once undersea due to the types of rock deposits
B. scientists assume an animal was a meat eater because of the teeth in its fossil
C. scientists assume an animal could climb trees because of its hand structure
D. scientists predict a volcano will erupt in the near future because of current volcanic activity

Answers

Answer: -

D. scientists predict a volcano will erupt in the near future because of current volcanic activity

Explanation: -

Reconstruction involves analyzing evidence present to understand what happened before. For example scientists assume an area was once undersea due to the types of rock deposits. The area was under sea before.

Scientists assume an animal was a meat eater because of the teeth in its fossil. Again the animal was before.

Scientists assume an animal could climb trees because of its hand structure . The animal existed before. Now no longer present.

But in D scientists predict a volcano will erupt in the near future because of current volcanic activity, the event of eruption could occur in the future. It has not happened already like in the previous cases.

A (n) blank is a vent or fissure in the earths surface through which magma and gases are expelled

Answers

Volcano is the answer I believe

Answer:

Volcanoes

Explanation:

The volcanoes are the features on the earth's surface through which the magma comes out along with other gases.

The formation of the volcano is associated with the divergent and the convergent type of plate boundary. Due to this motion and subduction of heavier plates, the plates at greater depth melts and mixes up with the uprising magma. This magma then rises up towards the surface in the over-riding plate, forming volcanoes, from where the magma erupts on the surface forming lava along with the emission of various gases such as carbon dioxide, sulfuric acid, and hydrogen sulfate.

What is the source of energy that is released in an exothermic reaction? what absorbs the energy that is released ?

Answers

Hello,

Here are your answers:

The proper answers to your questions are....

1. "Chemical bond energy is converted to kinetic energy"...... which causes it to release energy around its surroundings!

2. "Endothermic reactions"...... Endothermic reactions are the things that absorb the energy!

If you need anymore help feel free to ask me!

Hope this helps!

What evidence do scientists have that Earth has been hit by large objects, like asteroids, in the past? Check all that apply.

Answers

I have attached a screenshot of the question and its options.

Answer:
layer of burned organic matter
change in average global temperature
mass extinctions

Explanation:
Asteroids are external rocks/objects that hit the surface of the earth.
Let's check the options:
1- layer of volcanic ash: This option is rejected as volcanoes are caused as a result of the internal heat and combustion in the layers of the earth. Therefore, volcanoes are independent of external bodies as asteroids.

2- layer of burned organic matter: This option is accepted. When bodies , as asteroids, hit the earth, their clash with the earth's surface usually lead to burns and/or fires leading to layers of burnt organic matter that is found on the surface of the earth and its underlying layers.

3- change in average global temperature: This option is accepted as these bodies usually have different temperatures than that of the earth's climate. Therefore, when they penetrate the earth's atmosphere, they can lead to a change in the global temperature.

4- mass extinctions: This option is accepted as the collision of these bodies with the earth's surface can lead to destruction of creatures/objects which may lead to mass extinctions.

5- earthquake activity: This option is rejected as earthquakes are formed as a result of the motion of plates within the layer's of the earth and not as a result of external bodies.

Hope this helps :) 

How many moles of BaSO4 are formed if 0.5 moles of Na2 SO4 react with 60 g of BaCl2? Na2 SO4 + BaCl2 → BaSO4 + 2NaCl

Answers

the balanced equation for the reaction is as follows
Na₂SO₄ + BaCl₂ ----> 2NaCl + BaSO₄ 
stoichiometry of Na₂SO₄ to BaCl₂ is 1:1
first we need to find out which the limiting reactant is
limiting reactant is fully used up in the reaction.
                                                                           
number of Na2So4 moles - 0.5 mol number of BaCl2 moles - 60 g / 208 g/mol = 0.288 mol
since molar ratio is 1:1 equal number of moles of both reactants should react with each other
                                                                         
therefore BaCl2 is the limiting reactant and Na2SO4 is in excess. amount of product formed depends on number of limiting reactant present.
stoichiometry of BaCl₂ to BaSO₄ is 1:1.
                                                                           
therefore number of BaSO4 moles formed - 0.288 mol

Answer: 0.29

Explanation:

[tex]Na_2SO_4+BaCl_2\rightarrow BaSO_4+2NaCl[/tex]

To calculate the moles, we use the equation:

[tex]\text{Number of moles}=\frac{\text{Given mass}}{\textMolar mass}}[/tex]

Putting values in above equation, we get:

[tex]\text{Moles of}BaCl_2}=\frac{60g}{208g/mol}=0.29mol[/tex]

Moles of [tex]Na_2SO_4[/tex] = 0.5 moles

According to stochiometry, 1 mole of [tex]BaCl_2[/tex] reacts with 1 mole of [tex]Na_2SO_4[/tex]

Thus 0.29 moles of [tex]BaCl_2[/tex] will react with 0.29 moles of [tex]Na_2SO_4[/tex]

Thus [tex]BaCl_2[/tex] is the limiting reagent as it limits the formation of products and [tex]Na_2SO_4[/tex] is the excess reagent.

1 mole of [tex]BaCl_2[/tex] produces = 1 mole of [tex]BaSO_4[/tex]

0.29 moles of [tex]BaCl_2[/tex] will produce= 0.29 moles of [tex]BaSO_4[/tex]

The equation Mg(s) + 2HCl(aq) → MgCl2(aq) + H2(g) is an example of which type of reaction?

Answers

single-replacement reaction. hope it helped <3

Answer : This is an example of single-displacement reaction.

Explanation :

Single-displacement reaction : It is a type of reaction in which the more reactive metal displaces the least reactive metal from its solution.

It is represented as :

[tex]A+BC\rightarrow AC+B[/tex]

where A is the most reactive metal and BC is the compound in which the B is the least reactive metal which is displaced by the most reactive metal A.

The given balanced reaction is,

[tex]Mg(s)+2HCl(aq)\rightarrow MgCl_2(aq)+H_2(g)[/tex]

This reaction is an example of single-displacement reaction in which the magnesium metal displaces the hydrogen metal from its solution to give magnesium chloride and hydrogen gas as a product.

Hence, the given reaction is an example of single-displacement reaction.

Which equation shows conservation of mass? A.  H2O → H2 + O2 B.  PCl5 → PCl3 + Cl2 C.  Na + Cl2 → NaCl D.  Al + Br2 → AlBr3

Answers

Answer:

B. PCl₅ → PCl₃ + Cl₂.

Explanation:

The conservation of mass is a phenomena that is applicable and found in chemical reaction but only balance chemical reactions.Balanced chemical reaction means that: The number of atoms of the reactants = the number of atoms in the products.In balanced chemical reaction; the atoms that enter and participate in the reaction will result from it and maintain the mass of each atom.The first choice (A) is wrong that it is unbalanced chemical reaction,

H₂O → H₂ + O₂, the oxygen has 1 atom in the reactants side while has 2 atoms in the products side.

to be balanced and apply conservation of the mass it should be: H₂O → H₂ + 1/2O₂.

The second choice (B) is the right answer: PCl₅ → PCl₃ + Cl₂.

The number of atoms of P (1 atom) and Cl (5 atoms) are the same in both sides of reactants and products.

The third choice (C) is wrong that it is unbalanced chemical reaction,

Na + Cl₂ → NaCl, the Cl has 2 atoms in the in the reactants side while has 1 atom in the products side.

to be balanced and apply conservation of the mass it should be: Na + 1/2Cl₂ → NaCl.

The fourth choice (D) is wrong that it is unbalanced chemical reaction,

Al + Br₂ → AlBr₃, the Br has 2 atoms in the in the reactants side while has 3 atoms in the products side.

to be balanced and apply conservation of the mass it should be: 2Al + 3Br₂ → 2AlBr₃.

Final answer:

The law of conservation of mass states that matter cannot be created nor destroyed. In chemical equations, this is demonstrated by having an equal number of atoms for each element on both sides of the equation. Thus, the balanced chemical equation PCl5 → PCl3 + Cl2 shows the conservation of mass.

Explanation:

The principle of the conservation of mass is demonstrated by a balanced chemical equation, which has an equal number of each element's atoms on both sides. In the options given, the correct equation demonstrating mass conservation is PCl5 → PCl3 + Cl2. This equation rightly represents the law of conservation of mass as the number of atoms for each element is equal on both the reactant and the product side.

Out of the other options, H2O → H2 + O2 is incorrect because there is only 1 oxygen atom in the reactant side (in H2O) but 2 in the product side (in O2). Both Na + Cl2 → NaCl and Al + Br2 → AlBr3 do not conserve mass, as they don't have equal number of atoms for each element on both sides of the equation.

Remember, to show conservation of mass in a chemical reaction, the equation must be balanced, meaning it must contain equal atoms of each element on the reactant side and the product side, highlighting the fact that in any process, matter is neither created nor destroyed.

Learn more about Conservation of Mass here:

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When an electron moves to another orbital farther from the nucleus, does it gain or lose energy?

Answers

I believe that it loses energy, as it is moving away from the main power/control source.

HEELLP PLEEASEE I GIVE 30 POINTS + BRAINLIEST!!!!!! HELPP PLEEAASEE

Answers

You should be able to get the freezing water question. It is very important to know the difference between a chemical and a physical reaction. I'm going to ask that you try this one yourself.

Are you male or female? It won't help for this question. It would have if I'd known before hand. It will help me to answer you later on. Do you cook is the point? If you do, you should know something about what happens when you bake a cake. But you may not be able to guess, even if you do cook. How about dough rising (for bread or buns?) Is that chemical or physical? This time I'll tell you. It's chemical. 
To make a cake you need to blend a whole bunch of things together, sugar flour, eggs (most of the time). What happens? Do the look the same when you've finished baking?

That's right. Something new results especially to the egg. Chemical.

Burning a log is another common example. What are you left with after you've burned a log? Can you get the log back. Is there anything you can do to get the log back? If it was physical, you could. So what's left? And what do you see when you burn a log? Do you live where it snows? If you do, you must have seen a log burn. 

Which of the following is an example of a population?
Question 7 options:


all of the western diamondback rattlesnakes in Big Bend National Park


all plants and animals in Grand Canyon National Park


all leopard frogs in the world


all of the trees in Yellowstone National Park

Answers

All the western diamondback rattlesnakes in Big Bend national oark
Final answer:

In biology, a population is made up of all individuals of a specific species within a certain area. Thus, the example that best fits this definition is all of the western diamondback rattlesnakes in Big Bend National Park.

Explanation:

In biology, a population consists of all the individuals of a certain species living within a specific area. Therefore, the best example of a population among the options provided is all of the western diamondback rattlesnakes in Big Bend National Park. This is because this group contains only one species (western diamondback rattlesnakes) and is limited to a specific area (Big Bend National Park).

Alternatively, the other options contain either multiple specie (all plants and animals in Grand Canyon National Park and all of the trees in Yellowstone National Park) or include a species that is not confined to a specific area or region (all leopard frogs in the world).

Learn more about Population here:

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Helpp pleaseeeeeeeee

Answers

5 pm because she has to go 30 miles and she is only going -10 miles oer hour, which means in three hours she will het there

Answer:

The Sarah will arrive at 5.00 P.M..

Explanation:

Distance covered by Sarah = D = 30 miles

Time taken by Sarah to travel 30 miles = T

Speed by which Sarah cycling = S = 10 mile/hr

[tex]Speed=\frac{Distance}{Time}[/tex]

[tex]Time = \frac{Distance}{Speed}[/tex]

[tex]T=\frac{30 mile}{10 mile/hr}=3 hr[/tex]

Sarah will reach her grandmother's house in 3 hours.

If she leaves the home at 2.00 P.M. ,then she will reach at her grandmother's house by 5.00 P.M..

The reactant Zn is an

element
an ionic compound
a molecule
an oxide.

Answers

Zn is an element. It can be found in the periodic table of elements.
This is just an element.  Since there is no chemical or charge with the Zn it is just an element

If the wavelength of one wave is 0.25 or ¼ meters, how many waves will be formed in one meter?

Answers

4 waves will be formed.

How many milliliters are in 22 mm3?

Answers

fuf9chlbcoc cpchchlccpj hl hl hlxypcoyohcohchho. lh ohcgl vk .

An air mass of volume 6.5 x 10 to the fifth L starts at sea level, where the pressure is 775 mm HG. It rises up a mountain where the pressure is 622 mm HG. Assuming no change in temperature, what is the volume of the air mass?

Answers

From Boyle's law the volume of a fixed mass of a gas is inversely proportional to temperature at constant absolute temperature.
Thus, Vα1/P
    = V = k/P where k is a constant
P1V1=P2V2
Therefore; V2 = P1V1/P2
                       = ( 6.0 ×10^-5 × 775) /622
                       = 7.476 × 10^-5 L
Hence, the new volume of the air mass is 7.476 × 10^-5 L

how many liters of laughing gas are in 0.98 moles stp

Answers

3H2   +   N2 ===>   2NH3

GIVEN: 44.8 L of H2 at STP.

answer: mols of N2.

By applying ideal gas equation,

[tex]P\times V=n\times R\times T[\tex]

Where, P= pressure of gas

V=volume of gas

R=Gas constant

n=Number of moles of gas

T=Temperature

At STP, each gas has a defined value of pressure, volume and temperature.

P= 1 atm

R=0.0821 L atm mol⁻¹ K⁻¹

T= 0°C or 273 K

Putting all the values in the equation will give:

[tex]1\times V=0.98\times 0.0821\times 273[\tex]

V = 22 L

So the answer is 22 L.

How will the arrangement of salt particles most likely change?

Answers

Answer:

Salt particles will diffuse and towards where it is less that is left !!

so your answer is A !! left through diffusion !!

Explanation:

HELP FAST PLZ!!!!
which statement describes the role of decomposers in the carbon cycle?
A they release the carbon that remains in the bodies of dead organisms.
B they prevent carbon from escaping into the atmosphere
C they absorb carbon dioxide in the atmosphere
D they change carbon dioxide into a form that organisms can use.

Answers

b is the correct answer i hope this helps good luck on test.

Answer:

Your answer would be A.

Explanation:

I took a quiz with the same exact question

How many atoms of oxygen are in one formula unit of Al2(SO4)3? 4 6 7 12


What is the name of the compound Cr2(CO3)3?

Which of the following contains both ionic and covalent bonding?

NaClO
NO2
FeBr3
HI

Answers

1) aluminium sulfate has 12 atoms of oxygen (4 · 3 = 12).
2) name of the compound is chromium(III) carbonate. Chromium has oxidation number +3 and carbonate has -2.
3) NaClO contains both ionic and covalent bonding, ionic bond is between sodium and chlorine and covalent bond is between chlorine and oxygen.

Will mark as Brainliest.

Which of the following is an exothermic reaction?

melting ice

dissolving ammonium nitrate in water to cool the water

dissolving sugar in water

condensation

Answers

It is condensation, it is the answer.

What is a physical property of water?
A) liquid at room temperature
B) not flammable
C) pH of 7
D) reacts with sodium

Answers

A is the only physical property.  A physical property is one that does not involve another chemical or element.
a) liquid at room temperature

Both algae and amoeba are in the domain Eukarya. Which of the following characteristics do they most likely share?

They both belong to the plant kingdom.

They both have cells with no nucleus.

They both have cells with membrane-bound organelles.

They both belong to the animal kingdom.

Answers

Answer: They both have cells with membrane- bound organelles.

Explanation:

The domain eukarya includes the eukaryotic organisms, which range in diversity from single celled to multicellular. These organisms have cells that have membrane bound organelles, nucleus is present in them. These organisms range from simple to complex life cycles.

Hence, both algae and amoeba which belong to domain eukarya have membrane bound organelles in their cells.

Answer:

C, They both have cells with membrane-bound organelles.

Explanation:

I did the module exam

Properties such as luster, conductivity, and flexibility are used to describe what type of elements

Answers

Answer:

A.metals is the correct answer

Other Questions
Read the passage. Students may use cell phones between classes and during the lunch break, as long as they do not create a distraction or cause the student to be tardy for class. During class, cell phones will be secured in lockers or vehicles. Cell phones are not allowed in classrooms, locker rooms, or restrooms. Students may not use cell phones to take or transmit pictures. Cell phone use while on the bus is decided by the bus driver. Students who violate these rules will have their cell phones taken away until the end of the school year. What is the punishment for not following the schools cell phone rules? A) Cell phones will be taken away until the end of the school year. B)Cell phones will be taken away for a month. C)There is no punishment for breaking the rules. D)School officials will call the students parents. ABC is congruent to FGH, AB=8.3, BC=10.4, and CA=4.2. What is the measure of segment GH? Analyze the graph of the quadratic function that contains the points (0,-2), (1,0) and (3,10). Create the equation of the function given the three points. Having a little trouble with this question. Would greatly appreciate a little help, thank you! If a cell at metaphase of mitosis contains 20 sister chromatids, how many chromosomes will be present in a g1 cell Among 320 randomly selected airline travelers, the mean number of hours spent travelling per year is 24 hours and the standard deviation is 2.9. What is the margin of error, assuming a 90% confidence level? Round your answer to the nearest tenth. 0.01 What early American thinker from Virginia argued in 1776 that only treason and murder should be punishable by death? What the answer to simplifying( 6 to the power of negative 2) by (3 to the power of negative 3) and (36) to the power of 4 which describes the correlation shown? How were European rules rd guarded by the enlightment What is a lack of physical, social, or economic access to safe and nutritious foods called? A)famine B)food security C)food shortage D)food insecurity What is the most common crime to occur within families according to statistics?A. HomicideB. ArsonC. AssaultD. Burglary Find the required annual interest rate to the tenth of a percent for $5200 to grow to $6500 if interest is compounded quarterly for five years oxidation states of N2 + 3H2 --> 2NH3 Blue jays and robins do not interbreed. Assuming the blue jays and robins share the same habitat, describe the possible conditions that keep these birds repoductivly isolated. Explain your answer. Please help me with thisSimplify this expression:3 2/3x-4/5(x-3 3/4) The circumstance of a circle is 9pie cm. What is the diameter? Which of the following describes how Houyhnhnm's view death in Gulliver's Travels? It's an event of life, and they are not upset when one occurs. It's an event of life that is never discussed. It's an event of life that puts them in deep depression. It's an event of life that they do not talk about. What is the slope of a line that is parallel to y=5x+3 discuss how gender inequality in relationships could contribute to teenage pregnancy