nuclear decay occurs according to first-order kinetics. scandium-43 decays with a rate constant of 0.178 days–1. after 15.0 days, a sample has a mass of 1.73 g. what was the original mass of the sample?

The lungs, bronchi, and trachea seem to be cross-sectioned in the photo (windpipe). The respiratory system supplies oxygen and removes carbon dioxide, a waste product of cellular activity. The trachea transports air from the nose and mouth to the bronchi, which go to the lungs. The lungs exchange gases with the environment via breathing.

Generally, The picture appears to show a cross-section of the human respiratory system, including the lungs, bronchi, and trachea (windpipe). The respiratory system is responsible for bringing oxygen into the body and removing carbon dioxide, a waste product of cellular metabolism.

The trachea is a tube that carries air from the nose and mouth to the bronchi, which are smaller tubes that branch off from the trachea and lead to the lungs.

The lungs are the primary organs of the respiratory system and are responsible for exchanging gases with the environment through the process of breathing.

Read more about the respiratory system

https://brainly.com/question/4190530

#SPJ1

Oxygen and calcium react to generate calcium oxide. The chemical made of calcium and oxygen has the formula CaO. This reaction's chemical formula is 2Ca + O2 2CaO.

the eight types of chemical reactions that are most frequently encountered are: decomposition reaction, combination reaction, combustion reaction, single displacement reaction, double displacement reaction, precipitation reaction, and redox reaction.

The evolution of a gas, precipitate formation, color change, temperature change, and state change are significant aspects.

Learn more about redox reaction here:

https://brainly.com/question/13293425

#SPJ4

The change in internal energy for a molecule at 56 g/mol is discovered to be -539 kJ/mol.

The internal energy change of a reaction is represented by the symbol U. U = Heat of calorimeter + Heat of solution for a reaction in the bomb calorimeter.

Heat capacity = Heat Temperature

For example, 0.48 g compound U = 3.81 0.285 + 4.184 3000 0.28 g compound U = 4.67 kJ

For a molecule at 56 g/mol

U equals energy/mass/moles/one, where U = 4.67/0.48556 and U = 539 kJ/mol.

Since the reaction causes a temperature increase, the internal energy, or -539kJ/mol, is given a negative sign.

To know more about internal energy bvisit:-

https://brainly.com/question/11278589

#SPJ4

1000 g of water condenses at 100°C in a home radiator (changes from gas to liquid).

Equation

Q=m x Hvap

    where m= mass.

= 1000. gx2260J/g 

Q=2,260,000 J

What is Condensation?

Condensation, which is the opposite of vaporization, is the transformation of matter from its gaseous state into its liquid state. The water cycle is the most frequent use of the phrase. [1] Another way to describe it is as the transformation of water vapour into liquid water when it comes into touch with a solid, liquid, or cloud condensation nucleus in the atmosphere. Deposition is the term for the change that occurs when the gaseous phase directly transitions into the solid phase.

to know more about Condensation, visit to:-

https://brainly.com/question/5500097

#SPJ1

1.56% of the original sample would be left after 108 days.

What are radioactive element?

The atoms that make up radioactive elements have unstable nuclei, and as a means of achieving stability, they emit atomic radiation. Radioactive atoms are converted into another chemical element through radiation emission, which can either make the element stable or radioactive enough to cause additional decay.

Due to the extra nuclear charge present inside of some atomic nuclei, these unstable elements undergo radioactive decay to generate stable nuclei. These substances are referred to as radioactive substances.

Therefore, 1.56% of the original sample would be left after 108 days.

To learn more about radioactive element

Here: https://brainly.com/question/29619851

#SPJ4

The mole fraction of carbon dioxide in the mixture is

P(CO₂) = 0.00004 × 76mmHg

           = 0.304mmHg

The key to this problem is the fact that each component of a gas mixture contributes to the total pressure exerted by the mixture in proportion to the number of molecules in the mixture.

Partial pressures of gases are most often expressed as mole fractions.

                    P(gas) = χ(gas) × P(mixture)

This is the proportional to the number of molecules.

As you know, 1 mole of a substance is exactly 6.022⋅10²³

molecules of that substance. This is known as the Avogadro number Nₐ.

This means that the number of molecules, say x and Avogadro's number

No. can be used to express the number of moles of a gas.

             From a mole =  Number of Molecules × Nₐ

Now, the percentage composition of a gas mixture is the number of molecules each gas contributes to 100 molecules of the mixture.

In this case, the air must contain 0.04% carbon dioxide. This means that there are 0.04 CO₂ molecules in 100 air molecules.

For example, the number of moles of carbon dioxide in 100 air molecules is ⁿCO² = 0.04 molecules × Nₐ

            = 0.04 Nₐ

This air sample is

n (total) = 100 molecules × Nₐ

            = 100⋅Nₐ

This means that the mole fraction of carbon dioxide in the mixture is

P(CO₂) = 0.00004 × 76mmHg

           = 0.304mmHg

Learn more about Carbon Dioxide:

https://brainly.com/question/3049557

#SPJ4

The pH of an acidic buffer that contains equal concentrations of HC2H3O2 and NaC2H3O2 is 4.8.

These solutions are employed to keep environments acidic, as their name suggests. A weak acid and its salt are combined with a strong base to create an acid buffer, which has an acidic pH. The pH of an acetic acid and sodium acetate solution in water is equivalent at 4.74.

These solutions have PH values below seven.

These solutions are made up of a weak acid and its salt.

A mixture of sodium acetate and acetic acid (pH = 4.75) serves as an illustration of an acidic buffer solution.

Given;

Pka of acetic acid is 4.8;

conc of ch3cooh = conc of ch3cooNa;

now,

[salt]/[acid] = 1

now from the formula,

PH =  Pka + log([tex]\frac{conc of salt}{conc of acid}[/tex])

⇒PH = 4.8 + log(1)

⇒PH = 4.8 + 0

PH = 4.8

The pH of an acidic buffer that contains equal concentrations of HC2H3O2 and NaC2H3O2 is 4.8.

To refer more about Acidic buffers visit:

https://brainly.com/question/602584

#SPJ4

Answer:

The chemical formula changes

In order to design experiment we should initially know how the chemical will react with each other. When sodium chloride reacts with either of the chemicals following reactions takes place:

An inorganic substance having the chemical formula Pb(NO3)2 is lead(II) nitrate. In contrast to the majority of other lead(II) salts, it frequently appears as a colorless crystal or white powder and is soluble in water. Lead chloride and sodium nitrate precipitate are created when sodium chloride solution is introduced to a lead nitrate solution. Lead chloride precipitate is soluble in hot water but insoluble in cold water. If the initial concentrations of silver nitrate and sodium chloride are both quite high, there is a good possibility that the mixture of aqueous AgNO3 and aqueous NaCl compounds will produce a precipitate that is white in color. Therefore, the reaction between AgNO3 and NaCl is precipitation.

to know more about silver nitrate visit

https://brainly.com/question/29627918

#SPJ4

Answer:

[tex] \huge{ \boxed{0.255 \: \text{moles}}}[/tex]

Explanation:

To find the number of moles of a solution given it's volume and concentration/molarity, we use the formula;

[tex] \bold{c = \frac{n}{v}} \\ [/tex]

where

Since we're finding the number of moles, we make n the subject

[tex] \bold{n = c \times v}[/tex]

From the question;

[tex]n = 3 \times 0.085 = 0.255[/tex]

We have the final answer as

3 moles or 84.03 g of CO produces 3 moles of or 132 g of CO₂. Thus, the mass of CO required to produce 635 g of CO₂ is 404.23 g.

Carbon monoxide  is an inorganic gas produced from the covalent bonding  of carbon with oxygen. When carbon monoxide reacts with metal oxides it produces carbon dioxide.

From the given balanced reaction, 3 moles of CO produces 3 moles of CO₂.

Molar mass of CO = 28.01 g/mol, 3 moles =  (28.01 ×3) 84.03 g

molar mass of CO₂ = 44.01 g/mol , 3 moles = 132 g.

Thus, mass of CO required to produce 635 g of CO₂ is :

= (84.03 × 635 g) /132 g = 404.23 g.

Therefore, the mass of CO required to produce 635 g of CO₂ is 404.23 g.

To find more on CO, refer here:

https://brainly.com/question/10193078

#SPJ1

Answer:

Ferric Nitrate, Nitric oxide and water

Explanation:

Fe + dil. HNO3 gives iron nitrate along with NO . The resulting compounds would be ferric nitrate, nitric oxide, and water.

I hope this helped

Answer:

Ferric Nitrate, Nitric oxide and Water

Explanation:

Fe (NO3)3 , NO, H20

The products formed during the single displacement reaction between Al₂S₃ and Li are Li₂S₃ and Al.

What are deplacement reactions?

When a more reactive element pushes a less reactive element out of a compound that also contains the less reactive element, a displacement reaction takes place. The less reactive element has undergone a displacement reaction and is now pure and unmixed.

In the reaction of  Al₂S₃ and Li the following is observed:

Li+ Al₂S₃  = Li₂S₃ +Al

Lithium displaces aluminium here.

Hence the products formed during the single displacement reaction between Al₂S₃ and Li are Li₂S₃ and Al.

To know more about displacement reaction from the given link

https://brainly.com/question/7959057

#SPJ4

The edge length of a body-centered cubic unit cell made up of atoms of radius 178 pm is 411.074 pm.

The body-centered cubic unit cell is defined as an unit cell that has atoms at each of the eight corners of a cube (like the cubic unit cell) plus one atom present in the center of the cube. Each of the corner of  atoms is the corner of another cube so the corner atoms are shared among eight unit cells.

Length of body diagonal = r + 2r + r

                                         = 4r

From the cube, body diagonal = √(3) a

∴ 4r = √(3) a

Where:

a: is the edge length

R: is the radius of each atom = 178 pm      

By solving equation the equation for "a" we have:

a = 4r/√(3)

⇒ a = (4 × 178)/√(3)

⇒ a = 411.074 pm

Learn more about cubic unit cell from the link given below.

https://brainly.com/question/17157025

#SPJ4

Answer:

The Atom is a superhero character from DC Comics. He is a founding member of the Justice League and possesses the ability to shrink himself to subatomic size. In the comics, he is Ray Palmer, a scientist from Ivy Town.

Explanation:

Answer:

The effective nuclear charge is the net positive charge experienced by valence electrons.

Explanation:

The effective nuclear charge is the net positive charge experienced by valence electrons.

It can be approximated by the equation: Zeff = Z – S

Zeff = the effective nuclear charge

Z = denotes the number of protons existing in the nucleus

S = average amount of density between the nucleus and the electron.

The pH of the given solution would be 4.75.

What do you mean by pH?

pH is a measure of the acidity or alkalinity of a solution, usually expressed on a scale from 0 to 14. A pH of 7 is neutral, with solutions below 7 being acidic and solutions above 7 being alkaline.

The pH of the solution can be calculated using the Henderson-Hasselbalch equation:

pH = pKa + log([salt]/[acid])

Where pKa is the -log of the acid dissociation constant (in this case, 4.75 for acetic acid), [salt] is the molar concentration of the salt (in this case, 0.1 M for sodium acetate), and [acid] is the molar concentration of the acid (in this case, 0.1 M for acetic acid).

Plugging in the values, we get

pH = 4.75 + log(0.1/0.1)

pH = 4.75

Therefore, the pH of the solution is 4.75.

What is an acetic acid solution?

An acetic acid solution is a solution made up of acetic acid and water. Acetic acid, also known as ethanoic acid, is an organic acid which is the main component of vinegar. It has a strong, pungent odor and sour taste, and is used in many household products and industrial applications.

To know more about pH,

https://brainly.com/question/27905117

#SPJ4

Answer:

metalloid

Explanation:

Silicon. Silicon (symbol Si) is a group 14 metalloid.

K+ ions is more abundant in the interior of resting neuron that in the fluid surrounding the neuron.

What is a Neuron?

A neuron is a type of cell that is found in the nervous system and is responsible for sending and receiving electrical signals. Neurons are the basic building blocks of the nervous system and are responsible for processing and transmitting information throughout the body.

In neurons, potassium(K) ions are maintained at high concentrations within the cell while sodium ions are maintained at high concentrations outside of the cell. The cell has potassium and sodium leakage channels, which allow the cations to diffuse down their concentration gradients.

Define Potassium?

Potassium is basically a chemical element with the symbol K and atomic number 19. It is a silvery-white, soft, and ductile metal that is part of the alkali metal group. Potassium is an essential mineral for the body, playing a role in muscle contractions, nerve transmission, and the maintenance of a healthy fluid balance. It is also necessary for building and maintaining strong bones.

Therefore, the correct option is Option D.

To know more about neurons,

https://brainly.com/question/13061744

#SPJ4

rapid combustion

spontaneous combustion

explosive combustion

An unknown compound is xy has the x-to-y mass of ratio of 4.0. the decomposition of the compound xy will gives 20.0 grams of x, and  then will give grams of y  form is 5 g.

given that :

x/y = 4

The decomposition of the compound of xy will produces of x is = 20 g

mass of x = 20 g

therefore, x / y = 4

by cross multiplying   given equation we get :

x = 4y

y = x / 4

y = 20 / 4

y = 5 g

Thus, the mass of y will produces is given as follows :

y = 5 g.

To learn more about decomposition here

https://brainly.com/question/14553767

#SPJ4

1. The coefficient in 2H2O means that there are 2 moles of that compound for every 1 mole of CH4 and CO2. If you had 1 mole of CH4 (and enough O2), you would produce 2 moles of H2O. The coefficients describe the ratio of moles in an equation.

2. It's the same for O2. There are 2 moles of O2 for every 1 mole of CH4. When reacting O2 with CH4, you need 2 moles of O2 (which is important if you need to know how much O2 to react with CH4).

Polonium has a simple cubic cell(1 atom), manganese has a body-centered cube(2 atoms) and Silver is a face-centered cubic cell(4 atoms).

In each of the 3 unit cells of the metals, for every corner of the cell, there is 1/8th volume of the sphere. The total volume of the sphere is given by,

Total volume = 1/8th corner of cube x 8 Total Volume

                      = 1 sphere or atom

Hence, Polonium has only one atom in its cell whereas Manganese has 2 atoms in its cell, one in the corner and one in the center of the cell.

In the case of silver, apart from the corners in each of the faces, there is one hemisphere in each of the faces. There are 6 such faces in the cell. Therefore the number of atoms in silver is given by,

No of atoms in silver = 6 x 1/2 + 8 x 1/8

No of atoms in silver = 4 atoms in each cell.

In conclusion, it can be said that Polonium has a simple cubic cell, Manganese has a body-centered cube and Silver is a face-centered cubic cell.

To know more about lattice arrangement, click below:

https://brainly.com/question/28301565

#SPJ4

If molecules of hydrogen, nitrogen, oxygen, and chlorine have the same kinetic energy hydrogen molecule will move the fastest.

Kinetic energy will be defined as:

    K.E = 1/2mv2

In the above-mentioned equation:

   K.E = kinetic energy

   m = mass of gas molecules

   v = velocity of gas molecules

Gases with smaller particle sizes tend to be traveling quicker at a given temperature, which means that they have a greater speed. Kinetic energy enables gas particles to move at different rates, and these speeds are determined by the size of the gas particle.  Hydrogen gas particles are the smallest and hence move at a faster rate, followed by nitrogen gas particles, oxygen gas particles, and chlorine gas particles.

You can also learn about kinetic energy from the following question:

https://brainly.com/question/26472013

#SPJ4

Sulfur and copper combine to form the chemical compound copper (IV) sulphide (Cu2S). Cu2S, a chemical, is present.

What happens when CuSO4 and H2S combine?

When H2S gas is introduced to the blue CuSO4 solution, a black copper sulphide precipitate forms, and the sulphuric acid that was created stays in the solution. An illustration of is the response. a mixture reaction

What takes place when copper and H2S interact?

The surface of the copper rod will show signs of the purple-black copper sulphide product that results from the elemental copper reacting with hydrogen sulphide.

Learn more about Precipitation

Visit:

https://brainly.com/question/18109776

#SPJ1

The rate constant for the nuclide according to first-order kinetics is 0.3863 per day.

Nuclear Decay in First-Order Kinetics:

m(t) = Me∧(-αt)

where m(t) = mass of nuclide after decay at time t;

M = mass of nuclide before decay;

α = rate constant of decay;

t = time for the decay;

When a fixed percentage of the drug is excreted per unit of time, this is known as first-order kinetics.

For example, The amount of drug in the body has a direct relationship to the rate of removal. The amount of medication eliminated per unit of time increases with concentration. The medication concentration decreases by 50% for each half-life.

Now,

m(t) = Me∧(-αt)

⇒e∧(αt) = M/m(t)

applying ln on both sides;

αt = ln(m/m(t))

α = (ln(m/m(t))/t)

here t= 3.4 days, M = 45 grams, m(t) = 12.1 grams;

dropping these values in the above equation we get,

α = 0.3863 per day;

The rate constant for the nuclide according to first-order kinetics is 0.3863 per day.

To refer more about First Order Kinetics visit:

https://brainly.com/question/14977977

#SPJ4

Considering the Brønsted-Lowry theory, the correct answer is option B. a base can accept a hydrogen ion.

In the Brønsted-Lowry theory, a proton transfer occurs that requires the presence of a proton donor, that is, an acid, and a base that accepts them. In this way, the acid-base reaction is one in which the acid transfers a proton to a base.

Then, according to the Brønsted-Lowry Theory, a base is a substance capable of accepting protons (H⁺) in solution, and an acid is any species capable of donating a proton (H⁺).

According to the Brønsted-Lowry Theory, a base can accept a hydrogen ion.

Learn more about Brønsted-Lowry theory:

brainly.com/question/11597189

brainly.com/question/26939233

brainly.com/question/21736327

brainly.com/question/24098522

#SPJ1

The number of gas moles of molar mass 18g is 0.010moles.

Molar Mass is 18g and RMS speed 657 m/s , Kinetic energy is 42kj

42000=m(675 x 675)/2

m=84000/675²

=0.1843g

To find number of moles -

[tex]n=m/M[/tex]

n=calculated mass/Molar Mass

=0.010 moles

To find about number of gas moles -

https://brainly.com/question/18470626

#SPJ4

Based on the recipe for preparing the food, the limiting ingredient is the 2 cans of tomatoes.

The recipe for the food is given below:

Hence, 2 cans of diced tomatoes require 1 cup of green beans, 1/2 cup of pasta, 1 can of beans, and 4 of cups broth.

Hence, after, the 2 cans of diced tomatoes are used up, no more food can be prepared.

A limiting reagent or limiting ingredient is used up when cooking, hence, the 2 cans of tomatoes are the limiting ingredient.

Learn more about limiting reagent at; https://brainly.com/question/23661051

#SPJ1