Which of the following two cycles are the most closely related in their role in sustaining life?
a. carbon and nitrogen
b. water and nitrogen
c. carbon and oxygen
d. nitrogen and phosphorus please select the best answer from the choices provided a b c d

Answers

Answer 1
c because both are either used or is a waste product in all organisms
Answer 2

Answer: d. nitrogen and phosphorus

Nitrogen and phosphorus are important component of the genetic material present in the living organism, required for the expression of genes to perform a desire function in the living organisms. Both nitrogen and phosphorus are chief ingredients of the fertilizers required for the plant growth. Hence, nitrogen and phosphorous are two cycles that are most closely related in their role in sustaining life.


Related Questions

4NH3 + 5O2 4NO +6H2O

In an experiment, 3.25 g of NH3 are allowed to react with 3.50 g of O2. How many grams of NO are formed?

Please round final answers to the tenth position, one place after the decimal

Answers

Ask me anything if you have any doubt :-)

[tex]\boxed{2.6264752{\text{ g}}}[/tex] of NO is formed during the given reaction.

Further explanation:

Limiting reagent is the species or reagent in a chemical reaction according to which the amount of product is decided. It is completely consumed in the reaction.

Stoichiometry governs the amount of species present in the reaction by using the relationship between reactants and products.

The given reaction is as follows:

 [tex]{\text{4N}}{{\text{H}}_3} + {\text{5}}{{\text{O}}_2} \to {\text{4NO}} + 6{{\text{H}}_{\text{2}}}{\text{O}}[/tex]

The formula to calculate the moles of the substance is as follows:

[tex]{\text{Moles of substance}} = \dfrac{{{\text{Given mass of substance}}}}{{{\text{Molar mass of substance}}}}[/tex]             ...... (1)                                

Substitute 3.25 g for the given mass and 17.03 g/mol for the molar mass in equation (1) to calculate the moles of [tex]\text{NH}_3[/tex].

 [tex]\begin{aligned}{\text{Moles of N}}{{\text{H}}_3} &= \left( {\frac{{{\text{3}}{\text{.25 g}}}}{{17.03{\text{ g/mol}}}}} \right)\\&= 0.1908{\text{ mol}}\\\end{aligned}[/tex]

Substitute 3.50 g for the given mass and 31.98 g/mol for the molar mass in equation (1) to calculate the moles of [tex]\text{O}_2[/tex].

 [tex]\begin{aligned}{\text{Moles of }}{{\text{O}}_2} &= \left( {\frac{{{\text{3}}{\text{.50 g}}}}{{{\text{31}}{\text{.98 g/mol}}}}} \right)\\&= 0.1094{\text{ mol}}\\\end{aligned}[/tex]

According to the stoichiometry of this reaction, four moles of  reacts with five moles of [tex]\text{O}_2[/tex] to form four moles of NO and six moles of [tex]\text{H}_2\text{O}[/tex].

Calculate the moles of [tex]\text{O}_2[/tex] that react with and 0.1908 moles of [tex]\text{NH}_3[/tex] as follows:

[tex]\begin{aligned}{\text{Amount of }}{{\text{O}}_2} &= \left( {{\text{0}}{\text{.1908 mol N}}{{\text{H}}_3}} \right)\left( {\frac{{{\text{5 mol }}{{\text{O}}_2}}}{{4{\text{ mol N}}{{\text{H}}_3}}}} \right)\\&= 0.2385{\text{ mol }}{{\text{O}}_2}\\\end{aligned}[/tex]  

The above calculations concluded that 0.2385 moles of [tex]\text{O}_2[/tex] are needed to react with 0.1908 moles of [tex]\text{NH}_3[/tex] but only 0.1094 moles of  [tex]\text{O}_2[/tex] are present in the reaction mixture. Therefore, [tex]\text{O}_2[/tex] is present in limited quantity and is a limiting reagent.

Since [tex]\text{O}_2[/tex] comes out to be the limiting reagent, the formation of NO is governed by it. According to the reaction stoichiometry, five moles of [tex]\text{O}_2[/tex] produces four moles of NO. Therefore the amount of NO can be calculated as follows:

[tex]\begin{aligned}{\text{Amount of NO}} &= \left( {0.1094{\text{ mol }}{{\text{O}}_2}} \right)\left( {\frac{{4{\text{ mol NO}}}}{{5{\text{ mol }}{{\text{O}}_2}}}} \right)\\&= 0.08752{\text{ mol}}\\\end{aligned}[/tex]

Rearrange equation (1) to calculate the mass of the substance.

[tex]{\text{Mass of substance}}= \left( {{\text{Moles of substance}}} \right)\left( {{\text{Molar mass of substance}}} \right)[/tex]                     ...... (2)

Substitute 0.08752 mol for the moles and 30.01 g/mol for the molar mass in equation (2) to calculate the mass of NO.

 [tex]\begin{aligned}{\text{Mass of NO}} &= \left( {0.08752{\text{ mol}}} \right)\left( {30.01{\text{ g/mol}}} \right)\\&= 2.6264752{\text{ g}}\\\end{aligned}[/tex]

Learn more:

Calculate the moles of chlorine in 8 moles of carbon tetrachloride: https://brainly.com/question/3064603 How many grams of potassium was in the fertilizer? https://brainly.com/question/5105904

Answer details:

Grade: Senior School

Chapter: Mole concept

Subject: Chemistry

Keywords: limiting reagent, NH3, NO, H2O, O2, 2.6264752 g, moles, mass, molar mass.

In a machine shop, two cams are produced, one of aluminum and one of iron. Both cams have the same mass. Which cam is larger? (a) the aluminum cam (b) the iron cam (c) Both cams have the same size. ...?

Answers

The best and most correct answer among the choices provided by your question is the second choice or letter B.

The iron cam is larger than the aluminum cam even if with the same size.

I hope my answer has come to your help. Thank you for posting your question here in Brainly. We hope to answer more of your questions and inquiries soon. Have a nice day ahead!

Answer:

A - The aluminum can

Explanation:

Aluminum has a lower density than Iron does.

Imagine having a beachball sized ball of both aluminum and iron... The aluminum ball would be nice and light but that iron ball would definitely crush your toes if you dropped it on your foot! Even if they're the same exact size, they have totally different weights.

To fulfill the octet rule electron sharing leads to ____ electrons around each atom?
A. 4
B. 5
C. 6
D. 8

Answers

D. 8

You can predict it from it's name "Octet" means Eight. Atom must have that number of electron to have a stable structure!

Hope this helps!

A gas of unknown identity diffuses at a rate of 83.3 mL/s in a diffusion apparatus in which carbon dioxide diffuses at the rate of 102 mL/s. Calculate the molecular mass of the unknown gas. Give your answers in units of g/mol to three significant figures.

Answers

Answer: 65.7 g/mol

Explanation:

To calculate the rate of diffusion of gas, we use Graham's Law.

This law states that the rate of effusion or diffusion of gas is inversely proportional to the square root of the molar mass of the gas. The equation given by this law follows:

[tex]\text{Rate of diffusion}\propto \frac{1}{\sqrt{\text{Molar mass of the gas}}}[/tex]

[tex]\frac{Rate_{X}}{Rate_{CO_2}}=\sqrt{\frac{M_{CO_2}}{M_{X}}}[/tex]

[tex]\frac{83.3}{102}=\sqrt{\frac{44}{M_{X}}[/tex]

Squaring both sides and solving for [tex]M_{X}[/tex]

[tex]M_{X}=65.7g/mol[/tex]

Hence, the molar mas of unknown gas is 65.7 g/mol.

How many total atoms are in 0.240 g of P2O5?

Answers

Final answer:

To calculate the total number of atoms in 0.240 g of P2O5, you need to convert the mass to moles and then use Avogadro's number to find the total number of atoms.

Explanation:

To determine the total number of atoms in 0.240 g of P2O5, you first need to calculate the number of moles of P2O5 using its molar mass. The molar mass of P2O5 is 141.9446 g/mol. You can use the formula: moles = mass / molar mass. Plugging in the values gives: moles = 0.240 g / 141.9446 g/mol = 0.00169 mol.

Next, use Avogadro's number (6.022 x 10^23 atoms/mol) to calculate the total number of atoms. Multiply the number of moles by Avogadro's number:

total atoms = 0.00169 mol x 6.022 x 10^23 atoms/mol = 1.02 x 10^21 atoms.

Which is true about batteries?
A. They all contain graphite rods and zinc electrodes.
B. They all contain parallel cells that increase energy output.
C. They always contain different cells that work together to produce energy.
D.They often have identical cells in series to increase energy output

Answers

B. They all contain parallel cells that increase energy output.

Hope this helps!

Answer:

D.They often have identical cells in series to increase energy output

Explanation:

lol i stg thats the answer just took quiz on edge

some small hybrid cars and sport utility vehicles also have spoilers.what is their purpose? Is it the same or different from the spoiler on a sports car?

Answers

 Spoilers on hybrid cars and sport utility vehicles are usually designed to create a smoother, less turbulent airflow over the rear of the vehicle. This reduces drag (air friction). Sports car spoilers are most often designed to increase rolling friction, not to decrease air friction. Spoilers on different types of cars serve different purposes.
Final answer:

Spoilers in small hybrid cars, SUVs, and sports cars aim to reduce lift and drag and improve the grip of the car on the road. They are crucial for sports cars due to the high speeds involved. However, small hybrid cars and SUVs, contribute more towards aesthetics and fuel efficiency, but the principle of operation remains the same.

Explanation:

Spoilers are used in vehicles, including small hybrid cars and sport utility vehicles (SUVs), as well as sports cars, primarily to reduce lift and drag, and enhance the car's road grip. Generally, spoilers work on the principle of aerodynamics. For sports cars, in particular, the spoiler becomes more significant at high speeds, redirecting air flows to create a downward force that stabilizes the car, enhancing safety during high-speed maneuvers.

Although the purpose is fundamentally the same across all vehicles, the importance of spoilers may vary. In sports cars, with their high-speed indulgence, spoilers are essential components. On the other hand, for small hybrid cars and SUVs, brackets are used more for aesthetic appeal and fuel efficiency. However, the basic function of a spoiler in either scenario remains—to control airflow.

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Consider the following reaction:
2CH3OH(g)→2CH4(g)+O2(g)ΔH=+252.8kJ
Calculate the amount of heat transferred when 27.0g of CH3OH(g) is decomposed by this reaction at constant pressure.

If someone could help me with the steps I can figure it out on my own, thank you so much

Answers

Final answer:

To find the heat transferred, convert 27.0g CH3OH to moles, use the reaction's stoichiometry to determine heat per mole, and then multiply by the moles of CH3OH. The total heat transferred is 211.7 kJ.

Explanation:

To calculate the amount of heat transferred when 27.0g of CH3OH(g) is decomposed by the given reaction at constant pressure, follow these steps:

Convert the mass of CH3OH to moles using its molar mass (32.04 g/mol for CH3OH).Use the stoichiometry of the reaction to determine how much heat is produced per mole of CH3OH decomposed.Multiply the number of moles of CH3OH by the enthalpy change (ΔH) given for the reaction to find the total heat transferred.

Here's how to apply these steps:

Number of moles of CH3OH = 27.0 g / 32.04 g/mol = 0.842 moles.The reaction shows that ΔH for the decomposition of 2 moles of CH3OH is +252.8 kJ.Heat transferred = 0.842 moles * (252.8 kJ / 2 moles) = 211.7 kJ.

The heat transferred when 27.0 g of CH3OH(g) is decomposed by this reaction at constant pressure is 211.7 kJ.

what did paleomagnetism give strong evidence for A. Pangaea B. earth quakes C. Sea floor spreading D. magnetic storms

Answers

magnetic storms i guess i hope it helps have a nice day

Answer: The correct answer is (B).

Explanation:

Paleomagnetism : it is a branch of geophysics which deals with study of magnetism induced in rocks by the magnetic field of earth during their time of formation. It strongly supports the theory of tectonic plates by studying  magnetic field around the oceanic ridges.

When two plates rub against with each other earthquake is caused. Hence, it will be obvious to say that paleomagnetism give strong evidence for earth quakes.

Does elements in group 2 lend electrons

Answers

Group two is a metal, and metals form either metallic or ionic bonds. In ionic bonds, the metal and nonmetal transfer electrons, rather than sharing them as covalent bonds do. Also, it is do*** not does because the word "elements" is not singular. 

Yes, Group 2 elements, the alkaline earth metals, lose two electrons to form +2 ions, achieving a noble gas electron configuration, and are typically found as compounds due to their reactivity.

The elements in Group 2 of the periodic table are known as the alkaline earth metals. These elements, which include beryllium, magnesium, calcium, strontium, barium, and radium, have two electrons in their outermost energy level.

In chemical reactions, these Group 2 elements tend to lose two electrons to achieve a noble gas configuration, resulting in a +2 oxidation state. This is because they seek to have a full valence shell, similar to the nearest noble gas in the periodic table.

Group 17 elements (halogens) aim to gain one electron to complete their valence shells, while Group 14 elements have the ability to gain or lose four electrons depending on the context. Group 1 elements, also known as alkali metals, readily lose one electron in chemical reactions.

The chemical reactivity of alkaline earth metals is significant, but not as high as their Group 1 counterparts, due to the higher energy required to remove two electrons. Yet, they are reactive enough that they are not found free in nature, only in compound forms. The reactivity and the +2 oxidation state dominate the chemistry of Group 2 elements.

How does the absorption of ultraviolet radiation by the ozone layer help sustain life? a. This process helps maintain the temperature of the Earth. b. It keeps a low level of harmful ultraviolet radiation from reaching living organisms. c. This process keeps ozone concentrations in the troposphere at lower levels. d. All of the above are true.

Answers

answer d is correct in options

Answer: d. All of the above are true.

Explanation: Ozone is a protective shield present in earth's stratosphere which absorbs the harmful radiations from the sun and thus keeps a low level of harmful ultraviolet radiation from reaching living organisms.

As the sun rays are absorbed by the ozone layer, not all the sun rays reach the earth's surface and thus the temperature of the earth is also maintained.

The ozone present in the troposphere also called as ground level ozone is harmful as it can trigger a variety of health problems and is formed by reactions of pollutants from vehicular emissions in the presence of sunlight. Thus ozone in stratosphere blocks the sunlight and thus prevents the formation of ground level ozone.

Thus all the statements are true.

Selenium has six valence electrons. What is the valence of selenium?

Answers

Answer:

Two electrons because you need 8 electrons to make a atom stable and selenium has 6 electrons.

Explanation:

Final answer:

The valence of selenium, typically -2, refers to its combining power based on its six valence electrons with the configuration 4s²4p⁴. In compounds, selenium tends to gain two electrons to fill its valence shell.

Explanation:

The valence of selenium is the combining power of an element, especially as measured by the number of hydrogen atoms it can displace or combine with.

Selenium has six valence electrons, as indicated by its valence electron configuration: 4s²4p⁴. This means in the fourth energy level (n = 4 shell), selenium has a total of six electrons that can interact with other atoms to form chemical bonds. The valence of selenium can vary depending on the type of compound it forms; however, it is typically -2, as it often seeks to gain two electrons to fill its valence shell and achieve a stable noble gas configuration.

Why does hot air rise and cold air sink??

Answers

Explanation:

In hot air, molecules have more kinetic energy and due to this they move from one place to another. As a result, there occurs more number of collisions between the molecules. Due to this molecules of hot air tend to rise.

Whereas when air is cold then its molecules are closer to each other. As a result, they do not have enough kinetic energy and they do not move from their initial position.

Hence, cold air sinks because of lack of movement in its molecules.

Hot air is less denser than cold air, which is why hot air rises and cold air sinks.

The invisible gaseous cloud that envelops the Earth and reaches into space is called air. About 78% of it is nitrogen, 21% is oxygen, and the remaining 2% or so is made up of different contaminants, water vapour, carbon dioxide, and other trace gases.

Air molecules move more quickly when it warms near the surface of the Earth or on the first level of a building, producing more space between them and making the air less dense than the cooler air above it. Cooler, more dense air sinks while warmer, less dense air rises. Since cooler air's molecule bonds absorb less energy than hot air's, cooler air is denser and hence heavier.

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An organism that contains chloroplasts is able to produce food by the process of

Answers

An organism that contains chloroplasts is able to produce food by the process of "Photosynthesis"

Hope this helps!

_____ is a control mechanism that intensifies an earlier reaction. A sensory receptor An effector Negative feedback Positive feedback

Answers

Positive feedback is the answer.

The sensory receptors are nerve endings or specialized cells able to capture internal or external stimuli, and generate in response nerve impulses.

The answer is: A sensory receptor.

A scientist examining the periodic table sees that the element magnesium (Mg) has the atomic number of 12.

Based on this knowledge, what does the scientist immediately know is true about magnesium atoms?

Magnesium atoms have 12 protons.
Magnesium atoms have 6 protons and 6 electrons.
Magnesium atoms have 12 neutrons.
Magnesium atoms have 6 protons and 6 neutrons.

Answers

Atoms have protons, neutrons, and electrons.

The answer should be Magnesium atoms have 12 protons. This is because the atomic number of an element indicates how many protons there are. Hope this helps someone down the road!

Scientist call an organism that has two different alleles for a trait

Answers

they called the hybrids.

Why is charcoal a limited drawing medium?

Answers

the reason why charcoal is a limited drawing medium is: 
You can only draw in black and white

which very much limit your choice of color palette

hope this helps

What is the outermost layer of the earth?

Answers

The answer is the crust
The Earth's crust is the outermost layer of the earth.

Differentitate reversible and irreversible process

Answers

a revisable process, is a procces which you can "undo" for example: You mix water with salt, if you bring the water to 100 grade Celcius than you have them separated again

a procces like burning wood is not revisable (coz there is no way to turn ashes to wood)

I WIll upvote for answer
Balance the following reaction Fe^2 O ^3 +HCI+FeCI^3+H^2O

Answers

Let's balance step by step. We'll start with Iron (Fe)
Fe2O3 + HCl --> FeCl3 + H2O
We have 2 Fe on the left, and only one on the right, so we'll double the Fe on the right
Fe2O3 + HCl --> 2FeCl3 + H2O
Now we have six Cl on the right, and only one on the left, so we'll multiply the Cl by six on the left
Fe2O3 + 6HCl --> 2FeCl3 + H2O
Finally, we can balance the water, as we have 6 H and 3 O on the left, and 2 H and one O on the right, so we can triple the H2O on the right
Fe2O3 + 6HCl --> 2FeCl3 + 3H2O
The equation has been balanced.

Explain how line spectra are used to identify elements and what they indicate about atoms

Answers

Electron transitions from higher to lower energy levels cause emission of energy in the form of electromagnetic waves, each with their own specific wavelength. Because the energy levels of elements are quantized, each transition has a specific energy difference. The collection of these transitions makes up the emission spectrum and each spectrum is unique to a specific element, allowing identification.

how many sigma and pi bonds are there in phenol?

Answers

Phenol rocks 9 sigma (6 C-H, C-O, 2 O-H) and 3 pi bonds (1 C=O, 3 benzene ring).

There are 9 sigma bonds and 3 pi bonds in a phenol molecule.

Here's the step-by-step breakdown:

1. Sigma bonds:

Each single bond between carbon and hydrogen atoms is a sigma bond. There are 6 C-H bonds in the benzene ring, so there are 6 sigma bonds from these.There is one C-O single bond between the benzene ring and the hydroxyl group. This contributes another sigma bond.The O-H bond in the hydroxyl group is also a sigma bond.

2. Pi bonds:

The double bond between the carbon and oxygen atoms in the hydroxyl group consists of one sigma bond and one pi bond. So, there is one pi bond here.The benzene ring has a special delocalized structure with alternating single and double bonds. However, each of these bonds still involves one sigma bond and one pi bond. There are 3 double bonds in the benzene ring, so there are 3 pi bonds from these.

Therefore, in total, there are 9 sigma bonds (6 from C-H, 1 from C-O, 2 from O-H) and 3 pi bonds (1 from C=O, 3 from benzene ring) in a phenol molecule.

The complete question is here:

How many sigma and pi bonds are there in phenol?


2)
____________________ helps explain why there are a large number of marsupial mammal species in Australia and South America, two continents that were once connected.
A) Ozone production
B) Continental drift
C) The fifth mass extinction
Eliminate
D) The first mass extinction

Answers

The answer is B. Continental Drift (Confidently)

the equation A+X AX is the general equation for a(n)

Answers

The following equation is the general form representation of 1 of the common types of chemical reactions, and that are the synthesis reactions.

A + X => AX
This is synthesis, where an specifically an element combines chemically with another element to produce a more complex compound, composed of those 2 elements.


Alpha particles cannot penetrate deeply into solids because they _____.

have low mass

have high mass

have low velocity

have high velocity

have no mass

Answers

Answer: Option (c) is the correct answer.

Explanation:

A particle that contains two protons and two neutrons bounded together is known as an alpha particle.

It is known that an alpha particle has a large mass and due to this they travel very slowly. As a result, they tend to have low velocity.

Hence, we can conclude that alpha particles cannot penetrate deeply into solids because they have low velocity.

Final answer:

Alpha particles can't penetrate deeply into solids due to their high mass. Their large size slows their speed of movement and intensifies their interaction with other atoms, further limiting their penetrating power.

Explanation:

Alpha particles cannot penetrate deeply into solids because they have high mass. An alpha particle is a particle consisting of two protons and two neutrons, which gives it a relatively heavy mass. This high mass limits the speed at which it can move and the distance it can travel, especially in a dense medium like a solid. To put it in perspective, imagine trying to throw a heavy ball through a heavy curtain - the heavier the ball, the less distance it will cover within the curtain. Similar is the case with alpha particles. These particles also have a positive charge, which makes them intensely interactive with other atoms, further limiting their penetration power.

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COMPARE AND CONTRAST
PROPANE AND HEXANE ...?

Answers

In context|organic compound|lang=en terms the difference between propane and hexane is that propane is (organic compound) an aliphatic hydrocarbon, c3h8, a constituent of natural gas while hexane is (organic compound) any of five isomeric aliphatic hydrocarbons, c6h14 they are colorless, volatile liquids. As nouns the difference between propane and hexane is that propane is (organic compound) an aliphatic hydrocarbon, c3h8, a constituent of natural gas while hexane is (organic compound) any of five isomeric aliphatic hydrocarbons, c6h14 they are colorless, volatile liquids.


I hope my answer has come to your help. Thank you for posting your question here in Brainly. We hope to answer more of your questions and inquiries soon. Have a nice day ahead!

Why are carbon compounds that contain mercury and a greater environment concern than elemental mercury? ...?

Answers

Firstly mercury found in carbon compounds is more easily ingested and taken up by fish and therefore eaten by people causing poisoning. Found within carbon compounds it is also more likely to move up the food chain and become more concentrated.
Firstly mercury found in carbon compounds is more easily ingested and taken up by fish and therefore eaten by people causing poisoning. Found within carbon compounds it is also more likely to move up the food chain and become more concentrated.

Mexico City has an elevation of 7400 ft above sea level. Its normal atmospheric pressure is 589 mm Hg. At what temperature does water boil in Mexico City?

Answers

Final answer:

The boiling point of water in Mexico City, with an elevation of 7400 ft and an atmospheric pressure of 589 mm Hg, is lower than the sea level boiling point of 100°C. It would be approximately between 90°C and 95°C, although a nomogram or the Clausius-Clapeyron relation would be needed for a precise value.

Explanation:

At higher altitudes, such as Mexico City's elevation of 7400 ft, the atmospheric pressure is significantly lower than at sea level. This decreased pressure results in a lower boiling point of water. While the boiling point of water is 100°C at sea level (760 mm Hg), in Mexico City with an atmospheric pressure of 589 mm Hg, the boiling point is reduced. Based on Table 10.1.4, we can infer that as the altitude increases in places like Mexico City, the boiling point of water decreases. From Table 10.4.1, for example, we notice that at an elevation similar to Mexico City's, the boiling point can be several degrees lower than 100°C. Unfortunately, without the specific data for 589 mm Hg from these tables, we cannot give the exact boiling point temperature, but it would typically be between 90°C and 95°C.

To determine the exact boiling point at a specific altitude and pressure, such as Mexico City's, one would often use a nomogram or a formula derived from the Clausius-Clapeyron relation, which correlates temperature and pressure for the phase change between liquid and gas. To obtain a precise value for Mexico City, it is advisable to consult such a nomogram designed for this purpose.

Marie Curie was the recipient of two Nobel Prizes—a shared prize in physics and an individual prize in chemistry. Her chemistry prize was for discovering two new elements, polonium and radium. For what did she, her husband, and Henri Becquerel receive the physics prize?

-The discovery that radioactivity is an extensive property that can be measured precisely.
-The discovery that certain substances can phosphoresce.
-The discovery that radioactivity is caused by the decay of unstable atomic nuclei.
-The discovery that radioactivity can ionize gas in a chamber.

Answers

I just took the test and the answer is A. 
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