If the half-life of a radioactive element is 18 days, what percentage of the original sample would be left after 108 days?.

Answer: 1.00 L

Explanation: Pressure and Volume are inversely proportionate. The volume increases at a factor of 2, from 1.00 L to 2.00 L. This means the pressure would decrease by a factor of 2, from 4.00 atm to 2.00 atm. Think about it, if you had a box and it doubled in the space, the same amount of gas is still in the container and the pressure would be half as much as these gas particles would have half the amount of collisions against the walls

Final temperature is 30.3ºC

What is Temperature?

The term "temperature" refers to a measurement of an object's average kinetic energy, which is a category of energy linked to motion and used to describe how hot or cold an object is. But how hot and how frigid are they exactly? Hot and cool are not really scientific concepts. A physical scientist would check the metal's liquid state's temperature to find the answer. It is less confusing to use temperature instead of phrases like hot or cold.

The reaction's H is -6542 kJ as written. The heat produced by igniting 2 moles of C6H6(l) and producing 12 moles of CO2(g), for example, is represented by this.

We can determine moles of C6H6 combusted from the given mass of C6H6. We can then calculate the heat that would be produced based on that value. We can determine the change in water temperature after determining the amount of heat produced.

0.06785 moles are equal to 5.300 g C6H6 x 1 mol/78.11 g.

heat produced is equal to 221.9 kJ/0.06785 moles x 6542 kJ/2 moles.

q = mC∆T

(5.691 kg)(4.184 kJ/kg/deg)(T) = 221.9 kJ

T is equal to 221.9 kJ/(5.691 kg)(4.184 kJ/kg/deg).

T=9.3 degrees.

Final temperature equals 21° plus 9.3°, or 30.3°C

Learn more about Temperature from given link

brainly.com/question/24746268

#SPJ1

In an emission spectrum, the amount of visible light emitted during heating of metals is proportional to the number of protons and neutrons present in the nucleus.

Emission spectrum is defined as a spectrum of a chemical compound or substance composed of frequencies of electromagnetic radiation. Radiations which are emitted while electron make transition from higher to lower energy level.

Energy of photon is equal to the difference between the two energy states . There are many possible electronic transitions in an atom and every transition has a specific wavelength.

Learn more about emission spectrum,here:

https://brainly.com/question/27268130

#SPJ1

The two things that are credited with creating a global village is: Convenient air travel and Electronic media.

To learn more about Global Village here:

brainly.com/question/18920282

#SPJ4

Thus, the rate of disappearance of O₂ is 0.37 mol L⁻¹ s⁻¹ , the rate of appearance of CO₂ is 0.2467 mol L⁻¹ s⁻¹

The rate at which a chemical reaction moves forward is known as the reaction rate in chemistry. It is frequently defined in terms of either the concentration of a reactant that is consumed in a unit of time or the concentration of a product that is generated in a unit of time (amount per unit volume).

The equation becomes:

C₂H₄(g) + 3O₂(g) → 2CO₂(g) + 2H₂O(g)

Rate of reaction = [tex]-\frac{d[C_2H_4]}{dt}[/tex] = [tex]-\frac{1}{3} \frac{d[O_2]}{dt}[/tex] = [tex]+\frac{1}{2} \frac{d[CO_2]}{dt}[/tex] = [tex]+\frac{1}{2} \frac{d[H_2O]}{dt}[/tex]

It is given that, the rate of disappearance of O₂ is 0.37 mol L⁻¹ s⁻¹.

So, [tex]-\frac{1}{3} \frac{d[O_2]}{dt} =[/tex] [tex]+\frac{1}{2} \frac{d[CO_2]}{dt}[/tex]

or,  [tex]-\frac{1}{3} \frac{d[O_2]}{dt}[/tex]  × (-0.37 mol L⁻¹ s⁻¹) = [tex]\frac{d[CO_2]}{dt}[/tex]

or, [tex]\frac{2}{3} \frac{d[O_2]}{dt}[/tex]  × (0.37 mol L⁻¹ s⁻¹) = [tex]\frac{d[CO_2]}{dt}[/tex]

or, 0.2467 mol L⁻¹ s⁻¹ = [tex]\frac{d[CO_2]}{dt}[/tex]

Thus, the rate of disappearance of O₂ is 0.37 mol L⁻¹ s⁻¹ , the rate of appearance of CO₂ is 0.2467 mol L⁻¹ s⁻¹

To know more about rate of reaction refer to:

https://brainly.com/question/24795637

#SPJ1

Based on the nature of the acid as a triptotic acid, the molar mass of the acid is 247 g/mol.

What is a triprotic acid?

A triprotic acid is an acid which produces three moles of protons when dissolved in water.

The equation of the reaction at equivalence can be shown as follows;

H₃X + 3 NaOH ⇒ Na₃X + 3 H₃O

where X is the counter ion of the triprotic acid.

The ratio between the reacted acid and base at the third equivalence point = 1:3

The moles of substance reacted is calculated with the formula given below:

moles of substance reacted = molarity * volume

moles of NaOH reacted =  0.106M * 0.0352L = 0.003731 mole.

Thus, moles of H₃X reacted = 0.003731 moles /3

moles of H₃X reacted = 0.001244mole.

The molar mass of the acid can be calculated using the formula below:

molar mass =  mass /moles

molar mass of the acid = 0.307g / 0.001244mole

molar mass of acid = 247 g/mol

Therefore, the molar mass of the acid is 247 g/mol.

Learn more about molar mass click-

brainly.com/question/15476873

#SPJ4

The reaction's electron gain enthalopy is ΔH = -5591 kJ/ mol.(approximately)

An illustration of electron gain enthalpy ,As a result, an element's second electron gain entropy is positive. For instance, energy is released whenever an electron is attached to a sulfur atom to create an S- ion, whereas energy is needed whenever an electron is attached to an S- ion to create an S2- ion.

5N2O4 (l) + 4N2H3CH3 (l) ⇒ 12H2O (g) + 9N2 (g) + 4CO2 (g)

First, sketch the remaining product structures so that you can see the bonds. You ought to purchase the following:

H2O: H-O-H (pretend it's bent)

N2: N≡N

CO2: O=C=O

Step two is to research the average bond strengths of each component (reactants/productsbonds. )'s

Reactants:

N-N: 160 kJ/mol

N=O: 607 kJ/mol

N-O: 210 kJ/mol

N-H: 391 kJ/mol

C-N: 305 kJ/mol

C-H: 413 kJ/mol

Products:

O-H: 467 kJ/mol

N≡N: 941 kJ/mol

C=O: 799 kJ/mol (use the value with * since the bond is in CO2)

Step three is to count the quantity of each type of bond present in the reactants and products. The total bond strengths for every type of bond can then be determined by multiplying those values by the numbers in the balanced chemical equation above.

(For example, since the reactants include a total of nine N-N bonds—five from N2O4 and four from N2H3CH3—you multiply the covalent bond for N-N by nine, or nine times 160, to obtain a total of 1440 KJ/mol.)

Reactants:

N-N: 9*(160)= 1440 kJ/mol

N=O: 10*(607)= 6070 kJ/mol

N-O: 10*(210)= 2100 kJ/mol

N-H: 12*(391)= 4692 kJ/mol

C-N: 4*(305)= 1220 kJ/mol

C-H: 12*(413)= 4956 kJ/mol

Products:

O-H: 24*(467)= 11208 kJ/mol

N≡N: 9*(941)= 8469 kJ/mol

C=O: 8*(799)= 6392 kJ/mol

NOTE: In the balancing equation, I increased the binding energy for the two O-H bonds even by 12 H2O to get 24* for molecules like H2O. (467).

Add all the numbers for the reactants and the products respectively, in step four.

Reactants:

1440+6070+2100+4692+1220+4956= 20478 kJ/mol

Products:

11208+8469+6392= 26069 kJ/mol

In order to find ΔH in step five, remove the bond strengths for the product from the reactants.

ΔH= 20478 - 26069= -5591 kJ/ mol of rxn

To know more about electron gain enthalopy visit :

https://brainly.com/question/28391213

#SPJ4

The maximum mass of magnesium used in its reaction with HCl is 0.08gm so the total pressure does not exceed 1.5 atm.

We will use ideal gas laws to solve this

For the final pressure, P = 1.5 atm

Change in pressure = 1.5-1

= 0.5 atm

Volume = 0.161L

T= 298K

The equation of state for a synthetic perfect gas is known as the ideal gas law, sometimes known as the generic gas equation. Although it has significant drawbacks, it is a decent approximation of the behavior of many gases under various conditions.

Only an ideal gas or a real gas that behaves enough like an ideal gas can be approximated by the equation of state presented here (PV = nRT). The equation of state can be expressed in a wide variety of ways.

Let the moles of H, produced then

Using ideal gas law

P×V= n×R×T

0.5 × 0.161 = n × 0.0821 × 298

n=0.00329

Mg+ 2HCl⇒ Mg.Cl2 + H₂

Moles of H, 0.00329 1 mole of Mg gives 1 mole of H

Therefore, number of moles of Mg-0.0329

Mass of Mg=0.00329 × 24.3

Mass of Mg=0.08 gm

The maximum mass of magnesium used in its reaction with HCl is 0.08gm so the total pressure does not exceed 1.5 atm.

To refer more about ideal gases, visit:

https://brainly.com/question/24236411

#SPJ4

Answer:

[tex] \huge{ \boxed{89.54 \: g}}[/tex]

Explanation:

To find the mass of an object given it's volume and density, we use the formula;

[tex] \bold{density( \rho) = \frac{mass}{volume} \\ }[/tex]

Since the mass is the unknown variable in the question, we make mass the subject and solve.

mass = density × volume

From the question

[tex] \text{mass} = 1.21 \times 74 = 89.54[/tex]

We have the final answer as

Answer:

I hope this helped

Explanation:

An organelle is a subcellular structure that has one or more specific jobs to perform in the cell, much like an organ does in the body. Among the more important cell organelles are the nuclei, which store genetic information; mitochondria, which produce chemical energy; and ribosomes, which assemble proteins.

Answer: false

Explanation: Sodium reacts vigorously with cold water forming sodium hydroxide (NaOH) and hydrogen (H2). The reaction of sodium metal with water is highly heat producing due to which the hydrogen gas formed during the reaction catches fire and burns causing little explosions.

Magnesium metal does not react explosively with water…. Unlike the LOWER Group 2 metals, i.e. calcium, strontium, etc., the reaction of magnesium with water is rather sluggish… formation of magnesium oxide passivates (as it is called) the surface of the metal and prevents rapid oxidation…

No, EPA should not  grant the permit to raise fish off of the coast.

EPA full form is Environmental Protection Agency. To safeguard beaches, the EPA collaborates with states, tribes, territories, local governments, and the general public.

The EPA enforces various rules that restrict water pollution sources to our coastal beaches and ocean water.

(i) the Clean Water Act; 

(ii) the Clean Boating Act; and 

(iii) the Oil Pollution Act.

The EPA broadened its efforts to enhance the quality of coastal recreation waters and safeguard beach goers' health.

So, EPA should not grant the permit to raise fish off of the coast.

To know more about EPA refer to:

https://brainly.com/question/14956213

#SPJ1

Answer: Al(NO3)3 + 3NaOH ==> Al(OH)3 + 3NaNO3

Explanation:

NH₄NO₃ + NaOH ---> AlOH3 + 3NaNO3

Al(NO3)3 + 3NaOH ==> Al(OH)3 + 3NaNO3

Aluminium Nitrate + Sodium Hydroxide ----> Aluminium Hydroxide + Sodium  Nitrate

If the half-life of radium-226 is 1620 years. The for 55% decomposition of its original amount will take 1397 years.

Calculate the half-life by using the formula as,

A(t) = I(0.5)^t/t1/2

Where t1/2 = half life = 1620

Final amount, A(t) = 0.55 of its original amount = 0.55I

Hence, we have

0.55I = I(0.5)^t/1620

Taking the log of both sides we get,

log(0.55) = log(0.5)^t/1620

t/1620 = log(0.55) / log(0.5)

t/1620 = 0.8624964

t = 0.8624964 × 1620

t = 1397.2441

t = 1397 (nearest whole number)

Hence, for 55% decomposition of its original amount will take 1397 years.

Learn more about half life from the link given below.

https://brainly.com/question/14883322

#SPJ4

Answer:

To calculate the kinetic energy of an object, we use the formula KE = 1/2 * m * v^2, where KE is the kinetic energy, m is the mass of the object, and v is the velocity of the object. In this case, the kinetic energy of the cart would be calculated as follows: KE = 1/2 * 800 kg * 10 m/s^2 = 4000 J.

Explanation:

However, it's important to note that the kinetic energy of an object depends not only on its mass and velocity, but also on its height. In the case of a cart moving down a slope, the potential energy it has due to its height will be converted into kinetic energy as it moves. Therefore, in order to accurately calculate the kinetic energy of the cart, we would need to know its height relative to some reference point (such as the ground), as well as its velocity.

The gases changes its volume because there are no force holding the gas molecules together. Hence the option C is correct.

Gases do not have a definite shape or volume because the molecules in the gases are very loosely packed, they have large intermolecular spaces , hence they move around. The force of attraction between the molecules is also very less, as a result gases acquire any shape or any volume. In comparison to liquids and solids, intermolecular interactions between gas particle are weaker. Because the atoms in gases are loosely connected to one another, they can move more quickly than those in liquids. Thus, gases lack both a defined shape and a defined volume. They merely assume a container-like shape.

So,  gas molecules can break loose easily from any boundary and can fill  any space. Hence, they do not contain any definite volume.

To know more about properties of gases, please refer:

https://brainly.com/question/6140407

#SPJ4

Ka = [Cl3CCOO⁻] [H⁺] / [Cl3CCOOH] = 0.3

Ka = [C6H5 -NH2] [H30⁺] / [C6H5-NH3⁺] = 2.51ₓ10⁻⁵

Ka = [Cu (OH3)] ⁻[H⁺] ³/[Cu²⁺] = 3ₓ10⁻⁸

To know if a substance will act as an acid or a base in a reaction, we look at the functional group.

How to find acidic strength?

trichloroacetic acid (and carboxylic acids in general) have carboxylic group - O- H which dissociates into aqueous solution into COO⁻ + H+ ions. Since it gives protons in aqueous solution, it acts as an acid

Amines Ar -NH are bases. They react with water to produce hydroxide ions.

Protonated amine is the conjugate acid. It reacts with water to provide

Cu2+ reacts with water to provide protons. Hence, Cu2+ acts as an acid.

Among trichloroacetic acid, anilinium ion and Cu2+ ion, Ka value is maximum for trichloroacetic acid. Hence, trichloroacetic acid is the strongest acid.

Note: Higher is the Ka value, greater is the acid strength.

For more information about acidic strength please visit:

https://brainly.in/question/2426352

#SPJ4

ok

l. will give you two apple you have two equals to four 2+2=4

a situation when opposing forces or actions are in equilibrium, whether that balance is static (such as when forces are applied to a body and the resultant is zero) or dynamic (such as in a chemical process that is reversible when the velocities in both directions are equal): a condition of mental or emotional equilibrium.

What is a simple definition of equilibrium in chemistry?

When the rates of the forward and backward reactions are identical, chemical equilibrium is reached. In other words, there is no net change in the reactant and product concentrations.

Equilibrium in chemicals is a dynamic process. Even after equilibrium has been attained, the forward and reverse reactions still happen. However, for a reaction that is at equilibrium, there is no change in the relative concentrations of reactants and products because the reaction rates are the same.

The reaction, though, continues unabated. Instead, the process reaches a state of chemical equilibrium where the forward reaction is producing products as quickly as the reverse reaction is converting reactants into products.

To learn more about equilibrium visit:

https://brainly.com/question/28527601

#SPJ4

The phrase that describes a risk of using the radioisotope Co-60 in treating cancer is "increased biological exposure".

Use of Co-60 in treatment of cancer

The medical use of gamma rays from the radioisotope cobalt-60 to treat conditions such as cancer is known as Cobalt therapy. In the early 1950s, cobalt-60 was widely used in external beam radiotherapy (teletherapy) machines, which produces a beam of gamma rays which was directed into the patient's body to kill tumor tissue and treat cancer.

Hence, the use of Co-60 is now-a-days importantly used to treat conditions like cancer and the phrase used is "increased biological exposure".

Learn more about Cobalt-60 from the link given below.

https://brainly.com/question/18597667

#SPJ4

The difference between the atomic number and the mass number is atomic number is the total number of protons of an element, and atomic mass is the total number of neutrons and protons.

The nuclear charge number of an element is its atomic number. The total number of protons in the element's atoms serves as a representation of it.

The mass number of an element is often referred to as its atomic mass number and nucleon number. The mass numbers are the sum of the protons and neutrons.

The mass in protons and neutrons of an atom is expressed as a mass number, also referred to as an atomic mass unit. The atomic mass is the sum of the masses of all isotopes of a certain kind.

As a result, the atomic number of an element represents the total number of protons present, whereas the total number of neutrons and protons is represented by the atomic mass

To learn more about the atomic number and atomic mass, refer to the link:

brainly.com/question/14190064

#SPJ4

The equation for finding the mass of a system is:

mass = density x volume

where density is the mass per unit volume of a substance, and volume is the amount of space that a substance occupies.

To use this equation, you need to know the density and volume of the substance in question. For example, if you have a block of iron with a density of 7.8 g/cm^3 and a volume of 50 cm^3, you can find its mass using the equation above:

mass = density x volume

= 7.8 g/cm^3 x 50 cm^3

= 390 g

This means that the mass of the block of iron is 390 grams.

The emission wavelength (nm) of excited atoms are −54.44 eV.

The equation E=hc can be used to determine the emission line's wavelength. The energy difference between the excited state and ground level is indicated here by the symbols E, h, c, and.

An atom's ground state and excited state differ in energy by a factor of 31019 J.

Atoms that resemble hydrogen, i.e. The energy levels for H, He+, Li2+, etc. are provided by:

En=Z2 = 13:61 eVn2. where n is the quantum level and Z is the atomic number.

E2=−22⋅13.61 eV22. =−13.61 eV.

E1=−22⋅13.61 eV12. =−54.44 eV.

To know more about wavelength visit:-

https://brainly.com/question/12924624

#SPJ4

The concentration of solution is 0.0160M.

Option d) is correct

What is dilution equation?

When we dilute a solution by increasing the volume so as to decrease the molarity of the substance. By using this we can find the concentration.

M₁V₁=M₂V₂

M1 = initial molarity =0.200M

M2= Final molarity =M2

V1= Initial volume= 20mL

V2= Final volume = 250mL

Using this equation

0.200×20/1000 = M2×250/1000

⇒M2 = 0.400/ 25 = 0.0160M

For more information about dilution equation please visit:

https://brainly.com/question/29715909

#SPJ4

Chlorine is an element and carbon dioxide is a compound, this is the answer to the above question.

The matter is divided into categories using elements, compounds, and mixtures. Because all of the atoms in the simplest chemical compounds are the same size, they are referred to as elements. Compounds are made up of two or more elements that are chemically linked together in a certain sequence.

Elements, which are subcategories of atoms, may be defined by the same amount of protons. An element's atoms have the same number of protons, but its mass and number of neutrons may differ.

A compound is a substance that combines two or more distinct elemental kinds in a certain ratio of its atoms. During the process of fusion, some of the distinctive attributes of the constituent pieces are lost while the newly formed molecule picks up new traits. Compounds are represented using chemical formulae.

To know more about Chlorine visit:

https://brainly.com/question/14962130

#SPJ4

Answer:

Explanation:

chlorine is an element while carbon dyxoide is a compound

Si-30 has a 29.974 amu atomic mass and a 3.1% abundance. and silicon's typical atomic mass is 28.09 AMU.

The amount of matter that makes up an element's atom, or atomic mass. It is stated as a multiple of 1.992646547 1023 gram, which is equal to one-twelfth of the mass of the carbon-12 atom, which has an atomic mass of 12 units.

The mass of a single atom or isotope is referred to as its "atomic mass." An element's average weight compared to all of its isotopes and their proportionate abundances is known as its atomic weight. Isotope atomic masses have no bearing on atomic mass.

To know more about Atomic mass visit:

https://brainly.com/question/5661976

#SPJ1

Metals and non-metals come together to produce CaO ionic bonds. The only metals and non-metals, respectively, are calcium and oxygen. The remaining choices are covalent bonding (bonds between non-metals).

For more information on ionic bonds kindly visit to

https://brainly.com/question/11527546

#SPJ1

When an atom from group 2 of the periodic table(say X) reacts with an atom of group 17(say Y), then the general formula is XY₂.

The elements present in group 2 of the periodic table (Be, Mg, Ca, Sr, Ba, Ra) are metals having valency 2. On the other hand, the elements present in group 17 ( F, Cl, Br, I, At, Ts) are halogens or non-metals having valency 1. So, elements from both these groups combine together by transfer of electrons, forming an ionic bond between them.

The general formula is formed by exchange of valencies.

here, valency of X=2, Y=1

Thus, the general formula is XY₂

To know more about general formula here

https://brainly.com/question/2492579

#SPJ4