Question 4 (4 points)
(02.07 MC)
Title: CHM-U4-4.08-Std3a-4
Read the given expression.
X = number of protons - number of core electrons
Which of the following explains the identity of X and its trends across a period? (5 points)
O a
Oc
X is the effective nuclear charge, and it remains constant across a period.
X is the screening constant, and it remains constant across a period.
X is the effective nuclear charge, and it increases across a period.
X is the screening constant, and it increases across a period.
Next Page
Back

Consequently, v=hE=6. 61010 is the frequency of the light emitted.

The Rydberg Formula The Rydberg's Formula, 1=RZ2(1n2i1n2f), determines the wavelength of a photon absorbed by an electron transition. 1 = R Z 2 (1 n I 2 1 n f 2), where is the photon's wavelength, ni is the energy level's starting principal quantum number, and nf is the last principal quantum.

fλ = c

The equation f = c, where c is the speed of light, connects frequency (f) with wavelength (). Since the speed of light is constant, this equation must be maintained whether the frequency is increased or decreased because the wavelength must decrease.

To know more about frequency visit:-

https://brainly.com/question/5102661

#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

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

Inherited traits are defined as a trait  or a variant which is encoded by  DNA and passed from one generation to another.

DNA  is a hereditary material  which is present in human beings as well as all other living organisms.  Every cell which is present in an organism's body has DNA  which is the same. Most of the DNA is situated in the cell's nucleus and small amount of it can be found in the cell's mitochondria as well.

Information which is stored in DNA is stored as codes made up of four chemical bases namely, adenine, thymine , cytosine and guanine.Human DNA consists of 3 billion bases .The order of the bases determines information which is required for building and maintaining an organism.

Learn more about DNA ,here:

https://brainly.com/question/30006059

#SPJ1

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.

93.75 % of the Tc sample is remaining after 24 hours. The half life of the Tc is thus, 266 hours or 11 days.

Half life of a radioactive material is the time taken to decay its half amount. The decay constant k is related to the half life by the expression:

k = 0.693/ t1/2.

Radioactive decay is a first order reaction. Let N0 be the initial amount and Nt be the final amount and t be the time for decay, then,

k = 1/t ln (N0/Nt)

Given Nt = 93.75 %

N0 = 100%.

t = 24 hr.

K = ln (93.75 / 24 hr)/ 24 hr.

   = 0.0026 hr⁻¹.

Now the half life t1/2 = 0.693 / 0.0026 hr⁻¹

                                  = 266 hr = 11 days.

Therefore, the half life of the technetium sample is 11 days.

To find more on half life, refer here:

https://brainly.com/question/16387602

#SPJ1

Chlorine has the highest first ionization energy.

The ionization power is a degree of the capability of detail to enter into chemical reactions requiring ion formation or donation of electrons. it is also typically associated with the character of the chemical bonding inside the compounds fashioned by using the factors. See additionally binding power; electron affinity.

In physics and chemistry, ionization electricity, ionization power is the minimum strength required to remove the most loosely certain electron of an isolated gaseous atom, wonderful ion, or molecule.

On the periodic desk, first ionization strength commonly will increase as you circulate left to right throughout a length. that is because of increasing nuclear charge, which results in the outermost electron being greater strongly certain to the nucleus.

Learn more about ionization energy here:-https://brainly.com/question/13088843

#SPJ4

Atoms of hydrogen are then balanced. Watch the following video to learn more about oxygen atoms. C12H22O11 with 12O2 equals 12CO2 plus 11H2O.

Balance C12H22O11 + O2 CO2 + H2O

To Learn more About Atoms of hydrogen refer to:

https://brainly.com/question/20290989

#SPJ1

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

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

Concentrated solution that it would take to prepare 2.65 l of 0.515 m Hcl upon dilution with water is 131 ml.

A solution  that has a relatively large amount of dissolved solute is known a concentrated solution .

As we know,

And , moles of hydrochloric acid =  M₁ * V₁= M₂ * V₂

Now, V₁ =   V₂ * M₂/M₁

Given,

M₂ = 0.515 M

V₂ =2.65 L

As the hydrochloric acid can be concentrated up to 38% p/V ,

Therefore, maximum M₁ =38% p/V = 38 gr/ 0.1 L / 36.5 gr/mol = 10.41 M

Now, min V₁ =   V₂ * M₂/ max M₁

=  2.65 L* 0.515 M/ 10.41 M

= 0.131 L

= 131 ml

So, the quantity required can go from 131 ml up to 2900 ml ( if M₁ = M₂)

To know more about concentrated solution, refer

https://brainly.com/question/17206790

#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

The mass of NaF that will be produced when 7.6 g of [tex]F_2[/tex]  completely reacts with 23.2 g NaCl to produce 14.0 g of [tex]Cl_2[/tex] gas would be 16.80 grams.

From the balanced equation of the reaction between [tex]F_2[/tex] and NaCl below:

[tex]F_2 + 2NaCl -- > 2NaF + Cl_2 (g)[/tex]

The mole ratio of the 2 reactants is 1:2. We need to find the limiting reactant.

Recall that: mole = mass/molar mass

Molar mass of [tex]F_2[/tex] = 38 g/mol

Molar mass of NaCl = 58.44 g/mol

Mole of 7.6 g [tex]F_2[/tex] = 7.6/38 = 0.2 mol

Mole of 23.2 g NaCl = 23.2/58.44 = 0.40 mol

From the calculated moles, there is no excess reactant.

The mole ratio of NaCl to NaF is 1:1. Hence, the equivalent mole of NaF produced will also be 0.40 mol.

The molar mass of NaF is 41.99 g/mol.

Mass of 0.40 g NaF = 0.40 x 41.99

                                 = 16.80 grams

In other words, the amount of NaF that will be produced when 7.6 g of [tex]F_2[/tex]  completely reacts with 23.2 g NaCl to produce 14.0 g of [tex]Cl_2[/tex] gas would be 16.80 grams.

More on stoichiometric problems can be found here: https://brainly.com/question/28297916

#SPJ1

Answer: The higher the amplitude, the higher the energy.

Explanation: The higher the amplitude, the higher the energy. To summarise, waves carry energy. The amount of energy they carry is related to their frequency and their amplitude. The higher the frequency, the more energy, and the higher the amplitude, the more energy.

Molar mass of teflon polymer is 1,20,00,000. if on an average a teflon polymer has 100,000 monomer units and each monomer of teflon has the formula c2f4 =120.0g/mol.

no of monomer in teflon polymer is  100,000 monomer units ,

and  the formula of teflon is c2f4,

now the molar mass of monomer c2f4 is 100.02 g/mol then,

for  100,000 monomer units = 120.0*100,000 = 1,20,00,000 g/mol

Molar mass of teflon polymer is 1,20,00,000 g/mol.

The two that have received the attention are PFOA (also known as C8), which has been used for many years to manufacture Teflon non-stick, and PFOS, which is used to make Scotchgard water repellent. They don't degrade. PFAS are persistent and build up over time in both people and animals as well as in the environment.

The joining of hundreds of ethylene molecules to produce polyethylene is an illustration of the first type of reaction. Other addition polymers include polypropylene, which is created by polymerizing H2C=CHCH3, polystyrene, which is created from H2C=CH C6H5, and polyvinyl chloride, which is created from H2C=CHCl.

Learn more about PVC here:

https://brainly.com/question/26288847

#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

The balanced chemical equation for the reaction of sulfurous acid with lithium hydroxide to form water and lithium sulfite is given as below.

2 LiOH + H₂SO₃ → Li₂SO₃ + 2H₂O

The formula of lithium hydroxide is given as LiOH

The formula of sulfurous acid is given as H₂SO₃

the formula of lithium sulfite is given as Li₂SO₃

The reaction will be:

LiOH + H₂SO₃ → Li₂SO₃

Let us balance the equation

In order to balance Lithium will put two against LiOH.

2 LiOH + H₂SO₃ → Li₂SO₃

Sulfur is already balanced.

To balance oxygen add water to deficient side.

2 LiOH + H₂SO₃ → Li₂SO₃ + 2H₂O

This above reaction is the balanced equation.

Learn more about balanced chemical reaction from the link given below.

https://brainly.com/question/28659858

#SPJ4

A student dissolves 2.45 g of sugar in 200.0 g water. the mass percent of sugar in the solution is 1.22 %.

given that :

the mass of the solute =  2.45 g

the mass of the solution = 200 g

The mass percent formula is given as follows :

The mass % = ( mass of solute / mass of the solution ) × 100 %

The mass %  = ( 2.45 / 200 ) × 100 %

The mass % = 1.22 %.

Thus the mass percent of the 2.45 g of sugar dissolves in 200 g of the water is 1.22 %.

To learn more about mass percent here

https://brainly.com/question/7289343

#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

95 marks in 100 means you scored 95 % in homework.  Similarly 83% in labs and 77% in exams. Thus the weighted average will be 85 %.

Average of a set of values is their sum divided by their number. The average of a set with even number of values, will be their sum divided by number where the average comes in a range of the set of values.

Average of odd number of values will be the exact middle value of the set.

Given that marks in homework out of 100 = 95

labs = 83

exams = 77.

Thus, average of your marks percentage = (77 + 83 + 95)/3

                                                                     = 85%.

Therefore, the average percentage of the marks is 85%.

To find more on average, refer here:

https://brainly.com/question/27851466

#SPJ1

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 amount of the sodium-25 that will remain after half an hour, given that it has a half life of 1.0 minutes is 5.0×10⁻³¹ Kg

To obtain the amount that will remain after half hour, we'll begin by obtaining the number of half lives that has passed. Details below:  

n = t / t½

n = 30 / 1

n = 30

Now, we shall determine the amount that will remain after half hour. This is shown below:

N = N₀ / 2ⁿ

N = 1 / 2³⁰

N = 5.0×10⁻³¹ Kg

Thus, from the above calculation, we can conclude that the amount that would remain is 5.0×10⁻³¹ Kg

Learn more about amount remaining:

https://brainly.com/question/28440920

#SPJ1

A silver precipitate is created when silver nitrate, AgNO3, and magnesium bromide, MgBr2, are combined in aqueous solutions.Create the net ionic equation as well as the balanced formula equation for this reaction.

The end products of the reaction between aqueous systems of magnesium chloride (MgCl2) and silver nitrate (AgNO3) are solid silver chloride and aqueous magnesium nitrate.

The right response is (CH3)3C-Cl.The most reliable 3° carbocation is formed by tert-butyl chloride, or (CH3)3C - Cl.As a result, it will immediately produce the white precipitate of AgCl in AgNO3 solution.

To know more about ionic equation visit:

https://brainly.com/question/15467502

#SPJ4

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

The heat of combustion for TNT( 3406 kJ/mole) is smaller than that of sugar (5639 kJ/mole) because TNT is an explosive material.

As sugar is a non electrolyte, it is comparatively more stable. That is why, more energy is required to decompose the sugar. Therefore, heat of combustion value is 5639kJ/mol which is high.

The heat of combustion of TNT is about 3406 kJ/mol and this value is a good indicator of the energy available from the detonation of TNT.

TNT is sometimes used as a reagent in chemical synthesis, but is best known as an explosive material with convenient handling properties.

To know more about heat of combustion, refer

https://brainly.com/question/25109613

#SPJ4

The total heat that is required to produce the solid  is obtained as 34.8 kJ.

We know that the energy of the substance can be defined as the ability to do work. In this case, energy has been supplied to the system as the heat that is supplied to the substances.

There are stages that the objects would have to go through and in all these stages we have heat that is evolved or absorbed.

As the object cools from  120.9 °C to  87.9 °C

H = mcdT

m = mass of the object

c = specific heat capacity

dT = temperature change

H = 221.6 g *  1.5 J/g·°C * (87.9 °C - 120.9 °C)

H = -10,969 J or 10.969 kJ

As it is converted from gas to liquid;

H = 221.6 g/75 g/mol * 34.6 kJ/mol

H = 2.95 mol *  34.6 kJ/mol

H = 102.1 kJ

As the liquid cools from 87.9 °C to  -30.9 °C

H = 221.6 g * 2.4 J/g·°C * ( -30.9 °C - 87.9 °C)

H = -63.2 kJ

As the liquid changes to solid;

H =  221.6 g/75 g/mol * 6.3 kJ/mol

H = 2.95 mol * 6.3 kJ/mol

H = 18.6 kJ

As the solid cools further to  -61.9°C

H = 221.6 g * 4.9 J/g·°C * (-61.9°C - (-30.9 °C))

H = -33.7 kJ

Total heat involved;

10.969 kJ + 102.1 kJ - 63.2 kJ + 18.6 kJ - 33.7 kJ

= 34.8 kJ

Learn more about heat:https://brainly.com/question/28302909

#SPJ1

It takes 410.228 g of ethanol to dissolve in water to get 1.30l of vodka.

Soluble refers to things that dissolve in water. Examples of soluble materials are salt and sugar. The term "insoluble" refers to substances that do not dissolve in water. Examples of insoluble substances are wheat and sand.

An organic substance is ethanol. It is an alcohol with the molecular structure C2H6O. You may alternatively write its formula as C2H5OH or CH3CH2OH. A volatile, flammable, colorless liquid known as ethanol has a distinctive flavor and smell that is similar to wine.

When making 1.30 liters of vodha, how many grams of ethanol should be dissolved in water.

Formula of ethanol is C2H5OH.

2(C) = 2(12) = 24

5(H) = 5(1) = 5

1(O) =1(16) = 16

1(H) =1(1)= 1

adding them all to get molar mass

The molar mass of ethanol is 46g/mol

The concentration is expressed in molarity or moles solute per liters solution.

The molar mass of ethanol is 46 g/mol.

To obtain a 1.3 L of vodka,

the following stoichiometric calculation is done:

6.86 mol/L * 1.3 L * (46g/mol) = 410.228 g of ethanol is needed

410.228 g of ethanol is needed to be dissolved in water.

To know more about dissolved in water click:

brainly.com/question/12789799

#SPJ4

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…

The interactions between the solvent and the solute are either equal to or greater than the interactions between the solvent and the solute.

A solute can dissolve in a solvent to create a solution whether it is in a solid, liquid, or gaseous phase. A solute's solubility is the highest concentration that can dissolve in a solvent at a specific temperature.

Solvation is the scientific term for the interactions between solute particle and solvent molecule. Ions or molecules that are solvated are encircled by solvent. Photo from Wikimedia Commons of a sodium ion dissolved in water.

To know more about solution formation visit:-

https://brainly.com/question/13469356

#SPJ4