How many calories are needed to change a 9.8 grams of solid ammonia at -75 into a gas at room temperature 25 degrees c

Answers

Answer 1

The heat needed to change 9.8 grams of solid ammonia at -75 degrees C into a gas at room temperature 25 degrees C is 231 kJ.

What is solid ammonia?
With the formula NH₃, ammonia is a nitrogen and hydrogen inorganic chemical. Ammonia, the simplest pnictogen hydride and a stable binary hydride, is a colourless gas with a strong, pungent odour. It contributes considerably to the nutritional demands of terrestrial creatures by serving as a precursor to 45 percent of the world's food and fertilisers. Biologically, it is a common nitrogenous waste, especially among aquatic animals. About 70% of ammonia is used to create fertilisers, including urea and diammonium phosphate, in a variety of shapes and compositions. Additionally, pure ammonia is sprayed straight onto the ground. Ammonia is also a key ingredient in many commercial cleaning solutions and is a building component for the manufacture of numerous medicinal medicines.

The change in enthalpy, or heat, of a chemical reaction is equal to the change in internal energy of the system plus the work done on the system.
The enthalpy of a system is the sum of its internal energy and the product of its pressure and volume.
In order to change a solid into a gas, the enthalpy of the system must increase by the amount of heat needed to break the intermolecular attractions between the particles of the solid.

The heat of vaporization of ammonia is 23.6 kJ/mol.

Therefore, the heat needed to change 9.8 grams of solid ammonia at -75 degrees C into a gas at room temperature 25 degrees C is 9.8 * 23.6 = 231 kJ.

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Related Questions

What is the formula for ethanol according to this illustration?



Question 10 options:

A.C2OH6
B.COH2
C.C2O
D.C2OH

Answers

Answer:

[tex]{ \sf{C _{2} H_{6} O}}[/tex]

A metal tank containing hydrogen gas has a pressure gauge that reads 575 psi . What is causing the pressure inside of the tank ?

Answers

Answer:

The hydrogen molecules colliding with the sides of the metal tank.

Explanation:

Gas pressure is caused by the force exerted by gas molecules when colliding with the surfaces of objects.

For sn1 solvolysis of t-butyl chloride, rank the solvents from fastest reaction to slowest reaction.

Answers

Fastest: water.

Slowest: Acetic acid

What is sn1 reaction?

In organic chemistry, the SN1 reaction is a substitution reaction. Its name comes from the Hughes-Ingold symbol that shows how the reaction works. "SN" stands for "nucleophilic substitution," and "1" means that the step that controls the rate is unimolecular.

What is solvolysis?

Solvolysis is a chemical reaction in which the solvent, such as water or alcohol, is one of the reagents and is present in excessive amounts.

Hence, the Fastest: water formic acid methanol ethanol acetone

Slowest: Acetic acid

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Alkali metals are highly since they easily to form ion

Answers

It is a true statement that the alkali metals are highly reactive because they do form ions very easily.

What are alkali metals?

The alkali metals are the elements tat are found in group one. The elements in the group do not occur free in nature because they easily combine with other elements in such a way that they form compounds. This is why they have a very negative values of electrode potential. The electrode potential has to do with the ease with which an electron can be lost from a metal as manifested in the degree of negativity of the value of the electrode potential of the particular element that is under consideration.

Recall that the elements that have a very negative value of electrode potential does form an ion easily and as such they can loose or eliminate  the outermost single valence electron very much easily compared to the other elements.

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Missing parts;

Alkali metals are highly reactive since they easily form an ion.

True/false

Which Sl unit is most appropriate for measuring density

Answers

Answer:

g/cm^3

Explanation:

kg/m^3 is not most used for measuring density

Consider the following reaction at eqilibrium. What effect will removing H2O have on the system?

2 H2S+3 O2---> 2 H2O+ 2 SO2

a.The reaction will shift to the left
b. No change will be observed
c. The equilibrium constant will decrease
d. The equilibrium constant will increase
e. The reaction will shift in the direction of the products

Answers

The correct answer is option e, which says, The reaction will shift in the direction of the products on removing H₂O from the system.

According Le Chatelier's principle,

If the equilibrium of a chemical reaction system is disturbed by changing any property of the system, then the reaction will shift itself towards a that side which will reestablish the equilibrium of the system.

So, in the reaction,

2H₂S + 3O₂ → 2H₂O + 2SO₂

If we remove H₂O from the system, then the concentration of the product side will become less and the equilibrium of the reaction will get disturbed.

To compensate for the loss of the concentration of the product, the system will need more amount of H₂O to establish the equilibrium.

So, to make more products, more reactants would react with each other to form more amount of H₂O.

It means the reaction will shift towards right or we can say the reaction will shift towards the products side.

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how many moles of aluminum are necessary to generate 4.88 moles of aluminum oxide, according to the following equation:

4Al+3O2→2Al2O3

Answers

9.76 mol  moles of aluminum are necessary to generate 4.88 moles of aluminum oxide.

4.88 moles Al2O3 (4 moles Al / 2 moles Al2O3) = 9.76 moles Al

1 mol = 6.02214 ×[tex]10^{23}[/tex] particles

The mole is the amount of stuff in a system that includes the same number of atoms as there are in 0.012 kilogrammes of carbon 12; it is represented by the symbol "mol".

The Avogadro constant's numerical value is fixed to be precisely 6.022 141 29 1023 when it is expressed in the SI unit mol-1. The mole, symbol mol, is the SI unit of substance for an elementary entity that is specified, which may be an atom, molecule, ion, electron, any other particle, or a specified group of such particle.

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in what year and location did direct measurements begin to be taken of earth's atmospheric carbon dioxide? has co2 been increasing or decreasing since then?

Answers

C. David Keeling of the Scripps Institution of Oceanography started monitoring at a NOAA weather station in March 1958. In May 1974, NOAA began conducting its own separate and supplementary CO2 measurements.

In 1950, why did CO2 levels rise?

Then, in the 1950s, a sharp rise in the burning of fossil fuels—coal for power and steel production, oil for transportation, and natural gas for heating—dramatically boosted the rate of CO2 emissions into the atmosphere.

Since observations started in 1958, the amount of carbon dioxide (CO2) in the air at the Mauna Loa observatory in Hawaii has grown by more than 25%.

The average global CO2 concentration varied during the 800,000 years for which we have records, between 170 ppm and 280 ppm. Things changed quickly as people began to consume fossil fuels throughout the industrial age. The amount has only surpassed 300 ppm during the industrial period.

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The station's average monthly carbon dioxide observations since 1960 are depicted in his graph as parts per million. (ppm).

What the body experiences from carbon dioxide?

Numerous health effects from CO2 consumption might be observed. These indications can include a coma, hypoxia, convulsions, sweating, a tingling or pins-and-needles sensation, migraines, disorientation, agitation, a tingling and fasteners feeling, and difficulty breathing.

How is carbon dioxide produced?

Carbon dioxide (CO2) is produced from both natural (such as volcanoes, animal breath, and plant degradation) as well as anthropogenic sources (primarily the burning of fossils fuels like coal, oil and natural gas to generate energy).

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Why do Alkaline batteries eventually stop working & why cant they be recharged?

Answers

Answer:

Alkaline do not conduct electricity so they can't be recharged

Explanation:

base don't conduct electricity

While reading through a strange textbook on alien currency, you encounter the following word problem:

You are on an alien planet where the names for substances and the units of measures are very unfamiliar.

Nonetheless, you obtain 13 quibs of a substance called skvarnick.

You can trade this skvarnick for gold coins, but the vendors all measure skvarnick in units of sleps; not quibs.

5 quibs is equal to 7 sleps.

If you have 13 quibs of skvarnick, how many sleps do you have?

Based on the word problem above, what conversion factor are you given?

Question 3 options:

A.quibs
B.5 quibs = 7 sleps
C.7 sleps
D.13 quibs
E.5 quibs
F.sleps

Answers

Number of sleps we have is 7 sleps. Option B.

A conversion factor is a number used to convert one set of units to another set by multiplication or division. If the conversion is required, the values should be equal using the appropriate conversion factor. For example, when converting inches to feet, the equivalent conversion value is 12 inches or 1 foot.

The conversion factor is a fraction equal to multiplying a quantity by a conversion factor that changes the units in which the quantity is measured but does not change the original quantity of the quantity. The conversion factor is equal to 1 because it consists of an equal sign. To find the conversion factor using squares square on both sides of the conversion factor. To find the transforming factor that includes the dice cube on both sides of the transforming factor.

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a metal and nonmetal that have a large difference in electronegativity values will experience what type of bond?

Answers

Answer:

Explanation:

In a diatomic molecule with two identical atoms, there is no difference in electronegativity, so the bond is nonpolar or pure covalent. When the electronegativity difference is very large, as is the case between metals and nonmetals, the bonding is characterized as ionic.

Answer:

ionic

Explanation:

When the electronegativity difference is very large, as is the case between metals and nonmetals, the bonding is characterized as ionic.

suppose 15.00 ml of a solution of a monoprotic strong acid of unknown concentration requires 12.80 ml of a solution of 0.250 m naoh to reach the end point. what is the molarity of the strong acid?

Answers

The molarity of the strong acid is 0.21 M.

What is a strong acid?

Recall that a strong acid is an acid that is able to ionize completely in solution. So we now know that If we have an acid that can be able to break up in solution to give us the hydrogen ions and the hydroxide ions then what we have is a strong acid. On the other hand, a weak acid is an acid that is unable to ionize completely when it is in solution.

Having gotten our definitions right, we know that;

CA = molarity of the acid

CB = molarity of the base

VA = volume of the acid

VB = volume of the base

NA = number of moles of the acid

NB = number of moles of the base.

Given what we now have here;

CAVA/CBVB = NA/NB

CAVANB = CBVBNA

CA = CBVBNA/VANB

CA = 0.250 * 12.80 * 1/ 15.00 * 1

CA = 0.21 M

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Latent heat of vaporization of a substance, if 100 J converts 6 g of the substance from liquid to gaseous state, would be

Answers

We could use the following equation in order to solve this problem:

Replacing our values, we obtain:

The answer is 16.7J/g.

what are some importance of density?

Answers

Answer:

allows us to determine what substances will float and what substances will sink when placed in a liquid

Explanation:

Generally, substances float so long as their density is less than the density of the liquid they are placed in.

the half-life of radium-225 is 14.9 years. what is the annual decay rate? express the result to four decimal places.

Answers

The annual decay rate for the radium-225 having a half life of 14.9 years is 0.0465 year⁻¹

How do i determine the decay rate?

We know that half life is the time taken for half of a substance to decay.

The half life of a substance is related to the decay rate according to the following formula:

Decay rate (λ) = 0.693 / Half life (t½)

λ = 0.693 / t½

With the above formula, we can obtain the decay rate as illustrated below:

Half-life radium-225 (t½) = 14.9 yearsDecay rate (λ) =?

Decay rate (λ) = 0.693 / Half life (t½)

Decay rate (λ) = 0.693 / 14.9 years

Decay rate = 0.0465 year⁻¹

Thus, we can conclude that the decay rate is 0.0465 year⁻¹

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Which can be excluded from a list of objects in the solar system?(1 point)


planet


constellation


asteroid belt

sun

Answers

Answer:

The answer is a constellation

(20) SEP Engage in Argument Of all the noble gases, helium and neon, are completely
inert, as they do not form any chemical compounds. However, some of the heavier
noble gases, such as Kr, Xe, and Rn, are capable of forming a few chemical
compounds. Using periodic properties and electron configurations, explain how
this can occur moving down this group of elements.

Answers

Answer:

As you move down the periodic table, atomic radii increase (more shells in the electron configuration), and the first ionization energy decreases. Electrons of the outermost shell of the atom are further away, and their attraction to the nucleus, therefore, decreases, making it easier for elements with high electronegativity such as Fluorine to form compounds with them.

What is the answer to the question???

Answers

Answer:

7 valence electrons.

would be needed

7

Fluorine and neon have seven and eights dots

Can someone check my answers plssss? (**)- means answer
1. The Earth only has climate change because of human activity.
True
False**

2. The Earth is currently experiencing _____.
An Ice Age**
A Carbon Cycle Age
A Thermal Phase Change
An Interglacial Age

3. TRICKY QUESTION: What in one thing that scientists DO NOT use to study climate change? Choose only ONE Answer.
Number of Living trees
Pollen in bogs/lakes
Tree Rings
Ice core samples**

4. Why were the humans able to develop agriculture at the beginning of the Holocene Period?
Woolly mammoth herds left behind large numbers of animal droppings for fertilizer.
The ice from the previous ice age melted and the climate was warmer.**
Cave Men developed metal working technology that helped them make plows.
Holocene period men were able to select cold loving plants as crops.

5. TRICKY QUESTION: Humans impact the environment and the climate on the Earth. There are daily activities that you do that can affect coral reefs in oceans far away. What should you NOT DO where you live to help protect them?
Use less energy.
Plant trees/forest.
Use more water.**

Thank you <3

Answers

1. The Earth only has climate change because human activity is TRUE.

2.  The Earth is currently experiencing An Ice Age.

3. Ice core samples

4. The ice from the previous ice age melted and the climate was warmer.

5. Use more water.

Humans impact the physical environment in many ways including overpopulation pollution, burning of fossil fuels, and deforestation. Such changes are causing climate change soil erosion declining air quality and water unfit for drinking.

Pollution overfishing destructive fishing with dynamite and cyanide, collecting live corals for the aquarium market, mining corals for building materials, and climate warming are the many different things that humans do to coral reefs around the world every day. just a fraction of the damage. Climate change will lead to the Warming of the oceans causing heat stress that contributes to coral bleaching and infectious diseases.

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What is the ratio of argon-40 to potassium-40 two half-lives
after the rock has formed?

Answers

The ratio of argon-40 to potassium-40 two half-lives after the rock has formed is 7:1.

The half-life of a radioactive compound tells us the time needed for half of the atoms of any compound to go through the radioactive decay.

We know that, half-life of potassium-40 is 1.25 billion years because this is how long it takes for half of the number of atoms which are present in the sample to decay to argon-40.

The half-life of potassium-40 which decays by the beta emission is 1.28 × 10⁹ years. The half-life of potassium-40 which decays by the positron emission is 1.19 × 10¹⁰ years.

40 K which naturally occurs decays to the stable 40 Ar which is 11.2%, It happens by the capture of electron and by positron emission. It gets decayed to stable 40 Ca (88.8%) by emission of negatrons. Half-life of 40 K 1.25 x 10⁹ years.

The dating method of potassium-argon is specifically useful in determining the Lava age.

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The difference between Ionic bond and Covalent bond.

Answers

The difference between an ionic bond and a covalent bond is that ionic bod are made regardless if atoms are metal or nonmetal, while covalent bonds always are generated between non-metals atoms.

What is a covalent bond?

A covalent bond is a chemical bond between two atoms that are non-metals such as between hydrogen and oxygen atoms, while ionic bonds involve metals and non-metal atoms one example of this type of bond is the NaCl sodium chloride.

Therefore, with this information, we can conclude that ionic and covalent bonds are distinct due to the atoms that form the chemical bond.

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Sort the Physical Properties of Metals, Nonmetals, and Metalloids I will mark the brainiest

Answers

Answer:

Metals: Malleable, Conductor, Ductile, Luster
Nonmetals: Insulator, Brittle, Dull

Metalloids: Properties of BOTH Metals & Nonmetals

what is the change in internal energy (in j) of a system that absorbs 0.335 kj of heat from its surroundings and has 0.966 kcal of work done on it? give your answer in scientific notation.

Answers

The change in the internal energy is 4.395 kj

What is internal energy?

Rising temperature and changes in state as well as phase from solid state to liquid as well as liquid to gas cause an increase in internal energy. Planetary bodies could be viewed as a fusion of heat engines and heat reservoirs. Internal energy E is stored in the heat reservoirs, and some of it is converted into different kinds of mechanical, electrical, and chemical energies by the heat engines. The sum of the kinetic energy brought on by the molecule's movement and the potential energy brought on by the vibrational motion as well as electric energy of atoms inside of molecules makes up the internal energy U of the a system or a body with clearly defined boundaries. The energy contained in every chemical bond is also referred to as internal energy.

Given;

Q = +0.335 kj

W = - 0.966 kcal = -966 cal = - 4.04kj

del E int = +0.355 - [-4.04]

= 4.395 > 0

{Increase in internal energy}

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Select 2

Which of these are extensive properties?

1.a substance has a volume of 5.4 mL

2.a substance is very malleable (it can be hammered into a shape)

3.a substance has a melting point of 40°C

4.a substance has a mass of 1.25 g

5.a substance has a density of 4.13 g/cm³

Answers

1&4
Extensive properties means that the outcome or some type of measurement in dependent on the amount of the substance/sample.
Volume is dependent on amount of substance and so is mass

Why is downward displacement of water
unsuitable for collecting a gas that dissolves in
water?

Answers

Answer:

Answer Down below

Explanation:

Question answered: Why is downward displacement of water unsuitable for collecting a gas that dissolves in water?

: The reason why downward displacement of water unsuitable is bc  downward displacement of water as it is less denser than water. meaning it comes out of the surface water, that means it is insoluble in water so it does not dissolve in water.

Hope this helps

~~Wdfads~~

The answer is down below

Which statement best describes the effect of low ionization energies and low electronegativities on metallic bonding?

Answers

The  statement best describes the effect of low ionization energies and low electronegativities on metallic bonding is : Delocalization of the valence electrons is simple.

What is  ionization energy ?

Ionization energy, also known as ionization potential, is the amount of energy needed to remove an electron from an isolated atom or molecule in physics and chemistry.

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in a second trail, the student accidentally added more naoh(aq) to the flask than was needed to reach the end point, and then recorded the final volume. would this error increase, decrease, or have no effect on the calculated acid concentration for the second trial? justify your answer.

Answers

Error increase on the calculated acid concentration for the second trial.

What is titration?

By comparing an unknown solution to one with known concentration, a titration can be used to determine the concentration of the unknown solution. The titrant (the known solution) is normally added from a burette to a known volume of the analyte until the reaction is complete (the unknown solution).

If a little more NaOH solution was added, the color of the solution in the flask would become noticeably darker. Due to its sudden appearance, the endpoint must be avoided at all costs. A final volume is read from the burette once the titration reaches the endpoint. A final volume is read from the burette once the titration reaches the endpoint.

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An electrical drill has 100 J of chemical energy. Of the 100 J, 45 J are transformed into kinetic energy and 20 J are transformed into sound. The remaining energy is given off as thermal energy.


What is the thermal energy of the drill?

J

Answers

As per law of conservation of energy, the thermal energy of the drill is 35J.

Total energy = Kinetic energy + Sound energy+ Thermal energy

100 = 45+20+ Thermal energy

Thermal energy = 35J

The law of conservation of energy states that energy can neither be created nor destroyed -only converted from one shape of power to any other. because of this a system continually has the same amount of energy, until it's introduced from the out of doors.

The longer we go without making large modifications, the greater the chance of global warming and weather exchange grow to be in our daily lives. whilst we burn fossil fuels, they invent a terrific quantity of greenhouse gasoline emissions.

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Answer:

The answer above is correct! It's 35J :)

Explanation:

Just did it on Edge!

Hope this helped - brainliest would be very much appreciated!

Have a great day :D

How do you find the cation and anion to an element

Answers

In order to find the cation and anion of an element, the valence electron of the element needs to be determined.

Valence Electrons

The valence electron of an element is the number of electrons in the outermost shell of the atom of the element.

For example, sodium is an element with the atomic number 11. The electron configuration of sodium is 2, 8, 1.

In other words, sodium atom has a single electron in their outermost shell. Thus, the valence number of electrons in a sodium atom is 1.

In order for a sodium atom to form an ion, the valence electron needs to be donated. Thus:

[tex]Na - e^- -- > Na^+[/tex]

This means that elements form cations by donating their valence electrons. The number of electrons donated will determine the number of positive charges.

Once the valence electron is more than 4, atoms gain electrons to form ions rather than donating electrons.

For example, sulfur is an element with the atomic number 16. The electron configuration is 2,8,6. In other words, sulfur has 6 electrons in its outermost shell.

To form an ion:

[tex]S + 2e^- -- > S^2^-[/tex]

In summary, cations are formed when atoms donate electrons while anions are formed when atoms gain electrons.

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___CU(s) + ___HBr(s) -------> ?

Answers

Answer: This reaction will not occur, therefore it cannot be balanced.

Only certain metals reactive enough are able to replace a hydrogen on an acid. This only occurs if the metal is higher on the activity series than hydrogen. In this case Copper is not higher than Hydrogen on the activity series, thus it cannot replace the hydrogen. Meaning No Reaction.

Other Questions
please help!! I really need help please help when julia was doing research on her family tree she learned that she was not only of german heritage she was also italian. she bought a flag and also read italian history. this is an example of List three questions that you have about camouflage that you expect to be resolved by the readings. Write the number in standard notation.5.8 103 The cost of a family membership at a local gym is $20 for a parking permit plus $15 for each member of the family. express this cost as a function of the number of people in a family, x, using one car.(A) f(x) = 20x + 15(B) f(x) = 35x(C) f(x) = 15x + 20(D) f(x) = 20x + 1(E) f(x) = 15x + 1PLEASE ANSWER ASAP! I WILL GIVE YOU BRAINLIEST IF CORRECT! This graph shows how fast the international space station travels in orbit around Earth What is the meaning of the point with an x-coordinate of 3?A. In 1 second, the space station travels 3 miles B. In 3 seconds, the space station travels 3 miles in 15 miles.C. The space station travels 3 miles in 15 seconds D. It takes the space st 3 seconds to go 5 miles. How did many Americans view President Wilsons goal of establishing an international peacekeeping organization after World War I?They supported it because they wanted the United States to get more involved in world affairs.They opposed it because they feared that Wilson had made too many compromises in the Senate to get it passed.They supported it because they believed it would give the United States more prestige around the world.They opposed it because isolationist sentiment was growing, and many people feared American involvement in another war. routinized response behavior is what a consumer does when Which of the following are true?A.-2.7 4(x3)7x6 Responses Solve Each system of equations. -r + t = 5-2r+t=4 What purposes do exploring and preserving sites like Werowocomoco serve? Which would be the result if we divide the sum of 275 and 325 by 25? A. 25 B. 24 C. 20 D. 30 E. 40 17. it is recommended that hikers' backpacks weigh no more than 20% of their body weight on overnight bikes and no more than 10% of their body weight on day hikes there are restrictions a hiker who weighs 160 pounds is planning an overnight hike. the weight of her backpack when packed with essential equipment is 15 pounds. write an inequality to show how many pounds, p, the hiker can still add to her backpack and stay within the recommended weight a hiker who weighs 180 pounds is planning a day hike. the weight of his backpack when packed with part a part b when you are swimming, you apply a force to the water to move yourself forward. the greater the water pressure you apply, the faster you can swim. which of these statements from newton's laws of motion best explains this situation? A delivery truck is transporting boxes of two sizes: large and small. The large boxes weigh 40 pounds each, and the small boxes weigh 25 pounds each. There are 135 boxes in all. If the truck is carrying a total of 4350 pounds in boxes, how many of each type of box is it carrying?Number of large boxes:Number of small boxes: The greatest common factor of 36 and 60 is 12. Explain what this means. I need to find the inequality 5-12x Which expression is equivalent to 10x 6? Can someone help me with this, please? I really need help! Strontium-90 (Sr-90) has a half-life of approximately 29 years. Let the initial amount of Sr-90 in a sample be 100g. If the decay function s(y)=100*0.5^y/29 expresses the amount of Sr-90 that remains in the sample after y years, in how many years will 1g of Sr-90 be left? Round up your answer to the nearest number of years