1. Target I1
Which list of elements all have the same number of valence electrons?
a. F, CI, O, N
b. Cr, Mn, Fe, Co
C. Ne, Ar, Kr, Xe
d. Na, Mg, Al, Si

1. The mole fraction of the ionic species KCl in the solution is 0.035

2. The molarity of the KCl solution is 1.908 M

3. The molality of the KCl solution is 2.027 M

1. How to determine the mole fraction of KCl

The mole fraction of KCl can be obtained as illustrated below:

Mole fraction of KCl = Mole of KCl / total mole

Mole fraction of KCl = 0.456 / 12.956

Mole fraction of KCl = 0.035

2. How to determine the molarity of the KCl solution

The molarity of the KCl solution can be obtained as follow:

Molarity = mole / volume

Molarity of KCl = 0.456 / 0.239

Molarity of KCl = 1.908 M

3. How to determine the molality of KCl solution

The molality of the KCl solution can be obtained as follow:

Molality = mole / mass of water (in Kg)

Molality of KCl = 0.456 / 0.225

Molality of KCl = 2.027 M

Learn more about mole fraction, molarity and molality:

https://brainly.com/question/15735596

https://brainly.com/question/13386686

https://brainly.com/question/26921570

#SPJ1

There are 5 oxygen atoms in one nitrogen pentoxide. The number of oxygen atoms in one mole of nitrogen pentoxide is 3.01 × 10²⁴.

Any  substance containing 6.022 × 10²³ atoms is called one mole of the substance. This number is called Avogadro number. Hence, one mole of every element contains Avogadro number of its atoms.

One mole oxygen contains 6.022 × 10²³ oxygen atoms. Similarly one mole of a compound contains 6.022 × 10²³  number of its constituent molecules.

Now, the number of oxygen atoms in one mole of N₂O₅ will be 6.022 × 10²³ × 5 = 3.01 × 10²⁴. Therefore, option b is correct.

To find more on Avogadro number, refer here:

http://brainly.com/question/11907018

#SPJ1

Mole measure the number of elementary entities of a given substance that are present in a given sample. 6.02 x 10²³ oxygen atoms are

present in one mole of dinitrogen pentoxide N[tex]_2[/tex]O[tex]_5[/tex]. The correct option is option 4.

The SI unit of amount of substance in chemistry is mole. The mole is used to measure the quantity of amount of substance.

One mole of any substance contains  6.02 x 10²³ number of  atoms. 6.02 x 10²³ is called Avogadro number. Mole is inversely proportional to Avogadro number.

Therefore,  6.02 x 10²³ oxygen atoms are present in one mole of dinitrogen pentoxide. The correct option is option 4.

To know more about mole, here:

https://brainly.com/question/15209553

#SPJ1

Calcium sulfate, carbon dioxide, and water are produced when sulfuric acid and calcium carbonate interact.

The insoluble in water free lime (CaCO3) interacts with sulfuric acid. It takes only a few minutes for sulfuric acid and lime to react and produce gypsum. H2SO4 + Lime CaCO3 = CaSO4 (gypsum).

Each of these metals forms a layer of insoluble sulfate when exposed to sulfuric acid, which slows or stops the reaction altogether. A white precipitate of calcium sulfate and a small amount of hydrogen are formed in the calcium case.

To know more about calcium carbonate visit:-

https://brainly.com/question/13565765

#SPJ1

Answer:

algebraic reaction is the answer of this question

The pH and pOH of a substance with concentration of 5 × 10-⁵M is 4.30 and 9.70 respectively.

pH is a figure expressing the acidity or alkalinity of a solution on a logarithmic scale on which 7 is neutral, lower values are more acid and higher values more alkaline.

pH is really a measure of the relative amount of free hydrogen and hydroxyl ions in the water. pH is an important indicator of water that is changing chemically. pH is reported in "logarithmic units". Each number represents a 10-fold change in the acidity/alkalinity of the water.

The pH of a solution can be calculated by using the following expression:

pH = - log {H}

pH = - log {5 × 10-⁵}

pH = 4.30

pOH is a measure of the hydroxide ion concentration of a solution. As such, it can be used as an indicator of a substance’s alkalinity or even its electrical conductivity in some cases. The pOH is the negative logarithm of the hydroxide ion content and can be calculated by the expression:

pOH = 14 – pH

pOH = 14 - 4.30

pOH = 9.7

Learn more about pH and pOH at: https://brainly.com/question/17144456

#SPJ1

Christopher is a suspect who left his bloody fingerprints on the steering wheel of his car. A forensic scientist would transfer blood stains.

The most frequent sort of bloodstain pattern found at crime scenes is impact spatter. When anything touches a blood source, it happens. The blood in impact blood spatter patterns is frequently circular rather than elongated. Impact spatter comes in two varieties are rear spatter and forward spatter.

The crime scene team used an immunochromatographic technique to identify human blood qualitatively. Such testing is meant to be used sparingly at crime scenes when the human origin of suspected bloodstains is in doubt and when it is urgent to determine if the bloodstains are of human origin.

Thus, option A is correct.

To learn more about blood stain follow the link;

https://brainly.com/question/13767724

#SPJ1

The heat absorbed by the water when A\a chunk of iron at 90.6°C was added to 200.0 g of water at 15.5°C in a coffee cup calorimeter is 2257.2 joules and the mass of iron added is 69.44 grams

We know, Heat gained = mass of sample * temperature change * specific heat

thus a)  heat gained by water = 200g *(18.2-15.5) °C * 4.18 J/g°C = 2257.2 Joules

also since no heat lost to the surrounding we can say,

b) Heat lost by the chunk of iron = heat gained by water = 2257.2 Joules

or, heat gained by iron = -2257.2 Joules

using the same formula for chunk of iron,

Heat gained = mass of sample * temperature change * specific heat

-2257.2 J = mass of iron * (18.2-90.6)°C * 0.449 J/g°C

mass of iron = 2257.2/( 72.4 * 0.449 ) = 69.44 grams

To learn more about specific heat visit:

brainly.com/question/11297584

#SPJ1

The molarity of the acid is the 64.3dm³

Molarity is the amount of a substance in a certain volume of solution

Here given data is

25 cm³ of a solution of 0.1 mol dm-³ NaOH reacts with 51.5 cm³ of a solution of hydrochloric acid

We have to calculate molarity = ?

So the molarity = number of moles of solute/volume of solution in L or dm³

1. 25 cm³ = 1.25ml = volume

Molarity =  51.5 cm³ × 1.25ml

Molarity = 64.3dm³

Know more about molarity

https://brainly.com/question/4401006

#SPJ1

The concentration in parts per million of DDT are as follow:

3 x 10^-4 g in 2.3 kg minnow tissue PPM DDT is 0.13 ppm and in 717 µg in 1.5 kg breast milk is 0.478 ppm.

ppm DDT

PPM is defined as parts per million. It represents the lower concentration of the given solution. It also help in representing 0.001 gram or a milligram in the 1000 mL, which is equivalent to the 1 mg per liter.

Given,

A sample size of2.3 kg contained 3 x 10^-1 mg DDT

It means, 2.3 L sample contained 3 x 10^-1 mg DDT

Therefore, we can say that,

in part per million

= 3 x 10^-1 mg/ 2.3 L

= 0.13 mg/L

=0.13 ppm

A sample size of 1.5 kg contained 717 µg DDT

It means, 1.5 L sample contained 717 x 10^-3 mg DDT

Therefore, we can say that,

in part per million

= 717 x 10^-3 mg/ 1.5 L

= 0.478 mg/L

=0.478 ppm

Thus, we concluded that the concentration in parts per million of DDT are as follow:

3 x 10^-4 g in 2.3 kg minnow tissue PPM DDT is 0.13 ppm and in 717 µg in 1.5 kg breast milk is 0.478 ppm.

learn more about part per million:

https://brainly.com/question/12575653

#SPJ1

Chlorine and Aluminum atoms shielding effect on their outer electrons is in chlorine there is 7 electron and in aluminum there is poor shielding effect so the greater size of aluminum

An electron is the s sublevel shied electron present in the p sublevel of the same principal energy level and the electron shielding refer to the blocking of valence shell electron attraction by the nucleus due to the presence of inner shell electron and electron in an s orbital can shielding p electron at the same energy level because of the spherical shape of the s orbital and valence electron are the number of electron present in the outermost shell of an atom and now the last shell of the chlorine atom has 7 electron in it and in aluminum there is poor shielding effect so the greater size of aluminum

Know more about chlorine and aluminum

https://brainly.com/question/20512430

#SPJ1

C-F  bonds is likely to have the least ionic character

Ionic bond type is the linkage formed from the electrostatic attraction between oppositely charged ion in a chemical compound and if the electronegatively differences between two atom is high and there will be a more ionic character to the bond and if the electronegativity differences between the two atom is low and there will be less ionic character to the bond and therefore the smallest electronegativity differences means least ionic character will be found between O-F then C-F and H-f and finally the greatest electronegativity differences will be between Na-F is most

Know kore about bonds

https://brainly.com/question/14504067

#SPJ1

According to the reaction illustrated, the amount, in moles, of copper (II) nitrate that will be formed is 0.456 mole.

The equation of the chemical reaction when silver nitrate reacts with copper is expressed as follows:

[tex]2AgNO_3 + Cu --- > Cu(NO_3)_2 +2 Ag[/tex]

The copper was in excess. This means that silver nitrate is the limiting reactant.

And 0.912 moles of the silver nitrate were reacted.

The mole ratio of silver nitrate and copper (II) nitrate according to the balanced equation of the reaction is 2:1. In other words, for every 1 mole of silver nitrate that reacts, 0.5 moles of copper (II) nitrate is formed.

Now, if 0.912 moles of silver nitrate is involved, the equivalent amount of moles of copper (II) nitrate that will be formed can be calculated as follows:

2 moles silver nitrate = 1 mole copper (II) nitrate

0.912 moles silver nitrate = 0.912 x 1/2

                                          = 0.456 mole

In other words, according to the reaction given, if 0.912 moles silver nitrate is reacted with excess copper, 0.456 mole copper (II) nitrate will be formed.

More on stoichiometric problems can be found here: https://brainly.com/question/15047541

#SPJ1

It is the simplest whole number ratio of elements in a compound. Molecular formula is n times the empirical formula where n is integers 1,2,... The empirical formula is BH2N.

Empirical formula gives the proportion of the element that is present in a compound. It does not give information about the actual number or the arrangements of the atoms.

n= molecular formula÷ empirical formula

Molecular formula =B[tex]_3[/tex]H[tex]_6[/tex]N[tex]_3[/tex]

Molecular formula = 3×BH2N

Molecular formula =3×empirical formula

Empirical formula = BH2N

Therefore, the empirical formula for this compound B[tex]_3[/tex]H[tex]_6[/tex]N[tex]_3[/tex] is BH2N.

To know more about empirical formula, here:

https://brainly.com/question/14044066

#SPJ1

1.57 x 10²⁴ atoms of carbon to moles of carbon is 6.72 mole

Mole is the SI unit of amount of substance of a specified elementary entity

Here given data is

Atoms of carbon =  1.57 x 10²⁴

We have to calculate moles of carbon = ?

So one mole of carbon specifies 6.022×10²³ individual carbon atom that is mole of carbon

Then  1.57 × 10²⁴ atoms/6.022×10²³C×atom×mol⁻¹

Moles of carbon = 6.72 mole

Know more about carbon

https://brainly.com/question/15335284

#SPJ1

Answer:

200 (kg / mol) x dL

Explanation:

Answer:

53.7 L

Explanation:

The volume occupied by 35.2 g of methane gas at 25 °C and 1.0 atm. is 55.9 L.

Given to us is temperature, pressure, universal gas constant, and mass of methane gas, we need to find the volume occupied by the gas.

To calculate the volume occupied by the methane gas, we can use the ideal gas law equation:

PV = nRT

Where:

P = pressure (in atm)

V = volume (in liters)

n = number of moles

R = ideal gas constant (0.08206 Latm/(Kmol))

T = temperature (in Kelvin)

First, we need to convert the given temperature from Celsius to Kelvin:

T(K) = T(°C) + 273.15

T(K) = 25 °C + 273.15

T(K) = 298.15 K

Next, we calculate the number of moles of methane gas using its molar mass:

molar mass of CH₄ = 12.01 g/mol + 4(1.008 g/mol) = 16.04 g/mol

n = mass/molar mass

n = 35.2 g / 16.04 g/mol

n = 2.19 mol

Now we can substitute the values into the ideal gas law equation:

PV = nRT

V = (nRT) / P

V = (2.19 mol × 0.08206 Latm/(Kmol) ×298.15 K) / 1.0 atm

V = 55.9 L

Therefore, the volume occupied by 35.2 g of methane gas at 25 °C and 1.0 atm is 55.9 liters.

Learn more about the ideal gas equation here:

https://brainly.com/question/15379358

#SPJ2

If Huda sees an obvious set of fingerprints on a mirror at a crime scene, the way in which she could best preserve this evidence is to: C. use clear tape to lift the prints.

In English language, an evidence can be defined as a collection of factual information that comprises empirical statistics and analysis, which are typically used to show or prove that an action, event, message, etc., is credible, reliable, truthful, and verified.

In Forensics, there are different types of evidence that are used in combatting crimes and these include the following:

Additionally, it is very important and essential that forensic experts and scientist preserve any evidence that is seen or obtained from a crime scene, especially by choosing the most efficient and effective technique (method) such as using a clear tape to lift set of fingerprints on a mirror.

Read more on evidence here: brainly.com/question/28848551

#SPJ1

Answer: C

Explanation:

The relationship that exists between smooth endoplasmic reticulum and cell membrane is that lipids are produced in the smooth endoplasmic reticulum which is the major product used for the synthesis of cell membrane.

The cell membrane is defined as part of the cell that is semi permeable which surrounds the cells and controls the passage of substances in and out of the cell.

The endoplasmic reticulum is a membrane bound organelle that are of two types namely:

The smooth endoplasmic reticulum is defined as the type of endoplasmic reticulum that is involved in the synthesis of lipids such as cholesterol and phospholipids.

A relationship exists between the cell membrane and the smooth endoplasmic reticulum because the lipids required for the synthesis of cell membrane are being produced by the smooth endoplasmic reticulum.

Learn more about cell here:

https://brainly.com/question/26122239

#SPJ1

Answer:

Kc = 0.101 or 1.01*10^-1

Explanation:

Set up ICE table
2NH3 -> 3H2 + N2
I: 2 moles, 0 moles, 0 moles

C: -x moles   +y moles   +z moles

E: 1.25 moles 0+y moles   0+z moles

We know that x is 0.75 moles, since 2-0.75 is 1.25

for every mole of NH3 consumed, 1.5 moles of H2 are produced, and 0.5 moles of N2 are produced. If 0.75 moles of NH3 are consumed, then 1.5 * 0.75 moles of H2 are produced, and 1.5*0.5 moles of N2 are produced

so, y equals 1.5 * 0.75, which is 3/2 * 3/4, or 3/8, or 0.375 moles of H2 produced

z equals 1.5 * 0.5, which is 0.75 moles of N2 produced

Kc equals [tex]\frac{[N_2][H_2]^3}{[NH_3]^2}[/tex]

N2 = 0.75, N2 = 0.375, and NH3 = 1.25
So, Kc equals
(0.375 * 0.75^3)/(1.25^2), which equals 0.10125

Round to 3 sig figs to get 0.101

0.0001212598 is a long will it be for one-half of carbon-14 in a sample to remain.

A reaction's half-life is the amount of time needed for the reactant concentration to drop to half its initial value. The rate constant for a first-order reaction and its half-life are connected by the constant t1/2 = 0.693/k.

The half-life of carbon-14 is 5,730 40 years, meaning that during the following 5,730 years, half of the radioisotope that is present at any particular time will spontaneously disintegrate.

Carbon-14's 5715-year half-life

The decay constant needs to be determined.

We know the half-life equation.

t[tex]\frac{1}{2}[/tex] = 0.693/λ

where,

t1/2  ​is the half-life and λ is the decay constant

so,

λ = 0.693 / 5715 = 0.0001212598

To know more about half-life visit;-

https://brainly.com/question/24710827

#SPJ1

Answer: In one type of combination, called negative,or N-type,the impurity causes the germanium or silicon to emit free electrons. Arsenic, bismuth, and antimony are suitable impurities for this purpose.

Explanation:

The formal charge that is carried by the carbon atom is +1.

Let us recall that the formal charge is defined as the charge that an atom in a compound appears to  have. We know that the formal charge can be obtained by the use of the formula;

Formal Charge = [# valence electrons on neutral atom] – [(# lone electron pairs) + (½ # bonding electrons)]

Now applying this formula to the specie that we have here it would become;

Formal Charge = (4 - 0) + 1/2(6)

Formal Charge = 4 - 3

Formal Charge = 1

It then follows that the formal charge that would appear on the specie is +1 as shown in the image attached here.

Learn more about formal charge:https://brainly.com/question/11723212

#SPJ1

As per the balanced reaction, 3 moles of calcium hydroxide produce 2 moles of aluminium hydroxide and 3 moles of calcium sulphate. The number of moles of calcium sulphate to produce 1.40 moles of aluminium hydroxide is 2.1 moles. Thus 2.1 moles of calcium sulphate will be produced.

Calcium sulphate is an inorganic compound formed from reaction of calcium hydroxide with any sulphates. The balanced equation of the given reaction is written as:

[tex]\rm Al_{2}(SO_{4})_{3} + 3Ca(OH)_{2} \rightarrow 2 Al(OH)_{3} + 3 CaSO_{4}[/tex]

As per the balanced reaction,  3 moles of calcium hydroxide  2 moles of aluminium hydroxide.Given that 1.40 moles of aluminium hydroxide is produced. The number of moles of calcium hydroxide required for these much product is:

= (1.40 × 3) 2 = 2.1.

3 moles of calcium hydroxide produce 3 moles of calcium sulphate. Thus, 2.1 moles gives 2.1 moles of product. Hence, number of moles of calcium sulphate produced is 2.1 moles .

To find more on  balanced equation , refer here:

https://brainly.com/question/22064431

#SPJ1

Patrick is a 16 year old boy whose body has stopped producing osteoclasts this means for his bones that his bones will become weak and brittle and other part of his body like the hip and wrist and spine will be affected by this

Osteoclast weaken brittle bones and making them prone to breaking from even minor stresses like coughing or stopping and the most frequent location for fracture caused by osteoclasts are the hip writ and spine and bone is a living tissue that constantly degrade and is replaced and by increasing their resorptive activity and destroying bone to initiate normal bone repair and the cell known as osteoclasts mediate bone loss in pathogenic circumstances

Know more about bones

https://brainly.com/question/29427955

#SPJ1

In the following reaction HCO³⁻(aq) + H₂O(l) →CO₃²⁻ (aq) + H₃O⁺ (aq) is H₂O is a base and CO₃²⁻ is its conjugate acid

Whenever an acid donates a proton and the acid changes into a base and whenever a base accept a proton and an acid is formed an acid and base which differ only by the presence or absence of a proton are called a conjugate acid base pair so in the reaction

HCO³⁻(aq) + H₂O(l) → CO₃²⁻ (aq) + H₃O⁺ (aq)

H₂O is a base and CO₃²⁻ is its conjugate acid

Know more about conjugate acid base

https://brainly.com/question/17438439

#SPJ1

When the Carbon reacts with oxygen it produce CO₂. This can be depicted by the below equation.

C + O₂ → CO₂. By the given process, 57.2 g of CO₂ are produced.

It has been mentioned that when 15.6 g of C reacts with 52.1 g of O₂  , then 10.5 g of O₂ remains unreacted. It indicates that Carbon is the limiting reagent and hence the amount of CO₂ produced is based on the amount of Carbon burnt.

C + O₂ → CO₂

In the given equation , 1 mole of carbon reacts with the  1 mole of O₂ to produce 1 mole of CO₂.

In the case 15.6 g of Carbon reacts with 52.1 of O₂ to produce the  "x" g of CO₂.

No of moles of a substance = mass of  the substance/molar mass of  substance

No of moles of carbon = 15.6 /12= 1.3 moles

No of moles of O₂ = Mass of reacted O₂/Molar mass of O₂.

No of moles of O₂ = (Total mass of O₂ burned - Mass of unreacted O)/32

No of moles of O₂ = (52.1-10.5) ÷ 32 = 1.3 moles.

Hence as already discussed 1 mole of Carbon reacts with 1 mole of O₂ to produce 1 mole of CO₂. In this case 1.2 moles of carbon reacts with 1.3 moles of O₂ to produce 1.3 moles of CO₂.

Moles of carbon dioxide = Mass of CO₂ produced /Molar mass of CO₂

Mass of CO₂ produced(x) = Moles of CO₂ ×Molar mass of CO₂

Mass of CO₂ produced(x) = 1.3 x 44 =  57.2 g

Thus 57.2 g of CO₂ is produced.

To know more about formation of CO₂ , please refer:

https://brainly.com/question/15030226

#SPJ1

sutures are nonmoving joints that connect bones of the skull. These joints have serrated edges that lock together with fibers or connective tissue.