8) 0.450 moles of NaCl are dissolved in 145.0 mL of water. Calculate the molarity of the NaCl solution.

Explanation:

The half-life period is represented by the abbreviation P. The time that a material has suffered disintegration is represented by t. Thus, if we know the half-life and the disintegration time (represented by x), we can say how many half-lives a material has gone through until a certain moment. This is done through the relationship below:

t = x * P

With this knowledge, we can still determine the mass that remains after the half-life period from the expression:

m = mo/2^x

were m = mass left

mo = initial mass

x = half-life

Here we have:

P = 9 minutes

t = 27 minutes

x = ????

mo = 80 g

So first let's find x:

t = x*P

27 = x*9

x = 3

now let's find m:

m = mo/2^x

m = 80/2^3

m = 80/8

m = 10 g

Answer: b. 10

The wavelength (in pm) of the x-rays, given that it has a frequency of 2.74×10¹⁹ Hz is 10.9 pm

We understood that the velocity, wavelength and frequency of a wave are related according to the following equation:

Velocity (v) = wavelength (λ) × frequency (f)

v = λf

With the above equation, we can determine the wavelength. Details below.

The wavelength of the x-rays can be obtained as follow:

v = λf

3×10⁸ = λ × 2.74×10¹⁹

Divide both sides by 2.74×10¹⁹

λ = 3×10⁸ / 2.74×10¹⁹

λ = 1.09×10⁻¹¹ m

Multiply by 10¹² to express in picometer (pm)

λ = 1.09×10⁻¹¹ × 10¹²

λ = 10.9 pm

Thus, we can conclude that the wavelength is 10.9 pm

Learn more about wave:

https://brainly.com/question/260187

#SPJ1

The pH of a 0.63 M solution of carbonic acid is 0.2.

pH of a solution is a measure of how acidic or basic water is. The range goes from 0 - 14, with 7 being neutral. pH of less than 7 indicate acidity, whereas a pH of greater than 7 indicates a base.

pH is a measure of the relative amount of free hydrogen and hydroxyl ions {H⁺} in the water. The pH of a substance or solution can be calculated using the following formula:

pH = - log {H⁺}

According to this question, a carbonic acid has a concentration of 0.63M. The pH of the solution is as follows:

pH = - log {0.63}

pH = 0.2

Therefore, 0.63M of carbonic acid has a pH of 0.2.

Learn more about pH at: https://brainly.com/question/491373

#SPJ1

The energy of one quantum of blue light that has a frequency of 6.46 x 10¹⁴ s-¹ is 4.28 × 10-¹⁹J.

A photon refers to the quantum of light and other electromagnetic energy, regarded as a discrete particle having zero rest mass, no electric charge, and an indefinitely long lifetime.

The energy of a photon can be calculated by using the following formula:

E = hf

Where;

According to this question, blue light has a frequency of 6.46 x 10¹⁴ s-¹. The energy can be calculated as follows:

E = 6.626 × 10-³⁴ × 6.46 x 10¹⁴

E = 4.28 × 10-¹⁹J

Therefore, 4.28 × 10-¹⁹J is the energy of the blue light.

Learn more about energy at: https://brainly.com/question/2393994

#SPJ1

There are 3 nomenclature types, so you have to be attentive of which one it is:

Hydrochloric acid: It is a hydracid, it is composed only of the elements present in the name (hydrogen and chloride).

Copper (II) chloride: It's a salt composed of a metal and a halogen. The oxidation number of the halogen is -1 also in this case. This type of nomenclature tells us which is the oxidation number of the copper also, and it is the number between the parenthesis (+2).

Dinitrogen pentoxide: This type of nomenclature shows the number of atoms of each element present in the formula (di is 2, and penta is 5):

Aluminum sulfide: In the sulfides, there's the element named plus sulfur (with an oxidation number of -2). The aluminum only has +3 in its oxidation number:

Iron (II) nitride: In this case, the nitride means it's going to be nitrogen (with an oxidation number of -3) and the other element, in this case, iron (with an oxidation number of +2, as it says in the name):

The comparison is that Everyone has a partner when ballroom dancing, and groups dance together on a big stage, much like liquid water in a container. In this condition, water molecules form hydrogen bonds with one another, much as how couples dance in a ballroom.

In water vapor, particles move more freely and occasionally collide, as in the dance motion used in freestyle dancing.

Freestyle dancing is essentially improvising dance steps to a song on the fly without any prior choreography, so each dancer has their own unique dance. It is the same for water vapor since, as a gas, it flows in a variety of directions with each particle following its own unique path.

Note that on a molecular level, particles have less energy and mobility when they are in solid form (liquid water), whereas they have more energy and are more widely spaced out when they are in gas form (water vapor).

Learn more about particle movement from

https://brainly.com/question/28554949

#SPJ1

Answer:

The fertilizer has 0.3kg of nitrogen, 0.1kg of phosphorus and 0.8kg of potassium.

Explanation:

The series 12-4-32 indicates the percentage of each element in the fertilizer. So, in this case, there are 12% of nitrogen, 4% of phosphorus and 32% of potassium, and the rest will be oxygen.

knowing that the 100% of the fertilizer is equivalent to 2.5kg, we can calculate the mass of each element using a mathematical rule of three:

• Mass of Nitrogen:

• Mass of Phosphorus:

• Mass of potassium:

So, the fertilizer has 0.3kg of nitrogen, 0.1kg of phosphorus and 0.8kg of potassium.

The potential energy is 84.366 J.

We know that,  potential energy is PE= mgh

PE= 5.0 * 9.81 * 1.72

PE= 84.366 J

Potential energy is a form of stored energy that is dependent on the relationship between different system components. When a spring is compressed or stretched, its potential energy increases. If a steel ball is raised above the ground as opposed to falling to the ground, it has more potential energy. It is capable of performing more work when raised. Potential energy is a characteristic of systems rather than of particular bodies or particles; for instance, the system made up of Earth and the elevated ball has more potential energy as they become further apart.

To learn more about Potential energy  visit:https://brainly.com/question/24284560

#SPJ1

A car travels at 32.1 km/hour. The velocity of car in m/sec is 8.92 m/s.

Velocity is defined as the pace at which an object's location changes in relation to a frame of reference and time.

It can also be defined as the directional speed of a moving item as an indication of its rate of position change as seen from a specific frame of reference.

As we know 1 km = 1000m

                     1 hour = 3600 sec

So, 32.1 km = 32100 m

Velocity = distance / time

Velocity = 32100 / 3600

Velocity = 8.92 m/sec.

Thus, a car travels at 32.1 km/hour. The velocity of car in m/sec is 8.92 m/s.  

To learn more about velocity, refer to the link below:

https://brainly.com/question/18084516

#SPJ1

Answer:

Explanation:

i don't quite know what the question is here, but...

6+12=18  or Amanda's ball is heavier so the ball would have a hard time, again I don't know what the real question is here

Answer:

Amanda’s ball is heavier so it’s harder throw

Explanation:

Claim: The reason why Amanda was having such a hard time was because she choose a heavier ballEvidence: Jason had no problem with his ball which was 6lb but Amanda was struggle with double the weight of Jason’s ball weight which was 12lb having more mass.Reasoning: Jason picked up a ball with less mass weighting at 6 pounds but because of this his ball was much easier to roll. This was due to Newton’s second law since he had such a lighter ball it was easier for him to through. Newton’s second law is force equal mass times acceleration (f=ma). The opposite could be said about Amanda her ball was so heavy that’s why it was harder to throw. When the mass of Amanda's ball is thrown onto the alley it goes slower because it has much more mass to weight it down, giving the ball less acceleration. 

Answer:

=> 0.12428 M

Explanation:

To begin, write down a balanced equation;

Ca(HCO3)2 + 2HNO3 => Ca(NO3)2 + 2H2O + 2CO2

Then calculate the number of moles contained in 9.56 mL of 1.30M HNO3

We know that molarity is contained in 1000mL

1000 mL = 1.30 moles

9.56 mL = ?

= (9.56 × 1.30)/1000

= 0.012428 moles

Mole ratio

Ca(HCO3)2 : HNO3

1 : 2

But, xmoles : 0.012428 moles

x = 1/2 × 0.012428

= 0.006214 moles

This moles is contained in 50 mL solution.

50 mL = 0.006214 moles

1000 mL = ?

= (1000 × 0.006214)/50

= 0.12428M

Isotopes of certain _radioactive__ elements that spontaneously emit _radiation__ and _rays__ from the _nuclei___

Any of multiple species of the same chemical element with differing masses whose nuclei are unstable and spontaneously produce radiation in the form of alpha, beta, and gamma rays are known as radioactive isotopes, also known as radioisotopes, radionuclides, or radioactive nuclides.

Learn more about Isotopes here:

https://brainly.com/question/14220416

#SPJ13

To compare the effect of force on objects with different forces the acceleration must be constant and the air resistance have to be neglected.

Force is an external agent that acts on body to change it from the state of motion or rest. There are various kind of forces like gravitational force, frictional force, nuclear force etc.

In physics force is the product of mass and acceleration of a moving body. Thus F= ma. Hence, force is directly proportional to the mass and acceleration.

As the mass increases force acting on the body increases. Thus the force acting on 4 kg-metal will be higher.But to compare the same force on these three metal blocks, the acceleration must be constant. One more thing that the air resistance have to be neglected.

To find more about force, refer the link below:

https://brainly.com/question/26115859

#SPJ1

Area 1 is Noble gases, Area 2 is alkali metals,  Area 3 is metalloids, Area 4 is  alkaline earth metals, Area 5 is non-metal, Area 6 is transition metals and Area 7 is halogens .

In this question, we need to Select the label for each corresponding area . Area 1 is of Noble gases also known as group 18 of the periodic table. Area 2 is of alkali metals in group 1 of the periodic table.

Area 3 is of metalloids present in between of metals and non-metals in the periodic table . Area 4 is of alkaline earth metals in group 2 of the periodic table . Area 5 is of non-metal. Area 6 is of transition metals. Area 7 is of halogens  in group 17 of the periodic table.

To know more about periodic table refer to the link:

https://brainly.com/question/1173237

#SPJ1

Electrons are transferred from atoms of sodium to atoms of phosphorus this transfer makes the sodium atoms and the phosphorus atoms as a result, the sodium and phosphorus atoms strongly each other and it form sodium phosphide

Electron are smallest particles that make up an atom and they posses negative charge

Here given data is when electron are transferred from atom of sodium to the atom of phosphorous and this transfer made the sodium and phosphorous atom and because the form sodium phosphide because sodium is positive and phosphorous is negative and this positive negative are attracts and form sodium phosphide

Know more about Electrons

https://brainly.com/question/14660459

#SPJ1

Answer:

Carbon

Explanation:

Carbon is a special element that can form covalent compounds at any shape.

Fuels all consists of carbon.

If you study organic chemistry you will learn more about the miracles of carbon.

   Lye, commonly known as potassium hydroxide, is an inorganic substance with the chemical formula KOH. It is a powerful base that is also frequently referred to as caustic potash. It is applied in numerous manufacturing, industrial, and chemical processes.

3KOH(aq) + H3PO4(aq) ==> K3PO4(aq) + 3H2O(l).

According to this well balanced equation, we will produce ONE mole of K3PO4 from THREE moles of KOH.

Therefore, the first step is to determine how many moles of KOH are present in the current reaction.

moles KOH = 44.7 g KOH x 1 mol KOH/17.56 g = 3.44 moles KOH in the system at this time

How many moles of K3PO4 can we produce, then?

017.56 mole 3.44 moles of K3PO4 are created from 1 mol of K3PO4 and 1 mol of KOH.

To Learn more About Potassium hydroxide, Refer:

https://brainly.com/question/28330489

#SPJ13

In the modern periodic table, rows are known as the periods, which indicate the last electronic layer of an atom.

Columns are groups, which indicate the number of atoms in the last electronic layer.

Groups involve elements with similar properties, such as metals, non metals, actinides and lanthanides, halogens, noble gases, among others.

Blocks make reference to the orbitals in which the electron configuration end for each atom, those are s, p, d and f.

Answer:

the SI unit of force. It is equal to the force that would give a mass of one kilogram an acceleration of one metre per second per second, and is equivalent to 100,000 dynes.

Answer:

A newton is a unit of force

1.33 liters of O₂ is required to react with excess of CS₂ to produce 4 Liters of CO₂ gas.

The balanced chemical equation provided is,

CS₂(l) + 3O₂(g) → CO₂(g) + 2SO₂(g)

According to the reaction,

3 moles of O₂ forms one mole of CO₂.

So,

1 mole of O₂ = 1/3 moles of CO₂

We also know,

Amount of CO₂ formed is 4 L.

We also know,

Moles at 0°C and 1 atm = Volume of gas in liters/22.4

Moles of CO₂ = 4/22.4

Moles of CO₂ = 0.1785 moles.

Moles of O₂ required = 1/3 moles of CO₂

Moles of O₂ = 0.1785/3

Moles of O₂ = 0.0595

Volume of O₂ = Moles x 22.4

Volume = 0.0595 x 22.41

Volume = 1.33L

So, the volume of O₂ required is 1.33 Liters.

To know more about moles at STP, visit,

https://brainly.com/question/23803328

#SPJ9

The partial pressure of nitrogen, N₂ is 5moles .

A measure of concentration is the mole fraction. The mole fraction, which is denoted by "X," is used to calculate the relative amounts of solute and solvents in a solution. The ratio of the total number of moles in the solution to the number of moles of a particular component is known as the mole fraction.

Total moles of oxygen ,nitrogen and neon are 5+ 2+ 3+ =10 moles.

[tex]X_{N2}[/tex] = moles of N2/total moles of solution

=> 2/10 = 5moles

To know more about  mole fraction visit:-

https://brainly.com/question/2060778

#SPJ13

​

​

The connection between environmental stress and maturation in girls is that puberty occurs earlier in girls who have experienced chronic stress.

The term puberty refers to the time in the life a person in which secondary se--xual characteristics begin to occur. It is the time that a person begins to mature. This period could also be called the adolescence stage of  person.

When a developing person is at this stage, there are several kinds of characteristics that show that the person have arrived at this stage of life. ow we know that there is a connection between the  environmental stress and maturation in girls. This implies that as a result of environmental changes that some girl may seem to have an earlier or a later puberty. This can now explain the diversities in the times in which a girl does experience puberty as we know it now.

Learn more about puberty:https://brainly.com/question/27370083

#SPJ1

Energy would it take to heat a section of the copper tubing that weighs about 650.0g, from 15.83°C to 24.11°C is 2.072 KJ.

The formula heat energy is given by :

q = mcΔT

given that :

m = 650.0 g

specific heat of copper c = 0.385 J/g °C

T1 = 15.83°C

T2 =  24.11°C

ΔT = T2 - T1 =  24.11°C - 15.83°C = 8.28 °C

putting all the values in the formula :

q = mcΔT

q = 650.0 g × 0.385 J/g °C × 8.28 °C

q = 2072.2 J = 2.072 KJ

Thus, Energy would it take to heat a section of the copper tubing that weighs about 650.0g, from 15.83°C to 24.11°C is 2.072 KJ.

To learn more about heat energy here

https://brainly.com/question/15045931

#SPJ1

Explanation:

To solve this kind of problem we usually use the ideal gas law. The formula is:

P * V = n * R * T

Where P is the pressure, V is the volume, n is the number of moles, R is the ideal gas constant, T is the temperature. R is 0.082 atm*L/(mol*K), so we have to convert the temperature from °C to K and the pressure from mmHg to atm before solving the formula.

R = 0.082 atm*L/(mol*K)

V = 0.500 L

T(K) = T(°C) + 273.15 K

T(K) = 250 + 273.15 K

T(K) = 523.15 K

760 mmHg = 1 atm

P = 170 mmHg * 1 atm/(760 mmHg)

P = 0.224 atm

Now we can replace those values and solve the formula for the number of moles.

P * V = n * R * T

n = P * V/(R*T)

n = 0.224 atm * 0.500 L/(0.082 atm*L/(mol*K) * 523.15 K)

n = 0.00261 mol

Answer: There are 0.00261 mol in the sample.

If the temperature is 25 °C.

T = (273.15 + 25) K

T = 298.15 K

n = 0.224 atm * 0.500 L/(0.082 atm*L/(mol*K) * 298.15 K)

n = 0.00457 mol

Answer: There are 0.00457 mol in the sample.

The concentration of reactant B after one half-life is equal to 1.512M.

A reaction is said to be a second-order reaction when the overall order of the reaction is equal to two. Suppose the reaction can be represented as follows:

A  +  A  →  P

The rate of second-order reactions can also be written as r = kA²

The term k'' is the rate constant for the second-order reaction and the unit of the reaction rate (r) is moles per liter per second (molL⁻¹s⁻¹) and the unit of the second-order rate constant is M⁻¹s⁻¹.

The half-life of the second-order reaction is:

[tex]t_{\frac{1}{2} } = \frac{1}{B_oK}[/tex]

where B₀ is the initial concentration of reactant B.

Given the rate constant of the 2nd order reaction, k = 1.45× 10⁻³M⁻¹s⁻¹

The half-life of the reaction, [tex]t_{\frac{1}{2} } = 228 sec[/tex]

B₀ = 1/ (1.45× 10⁻³) × 228

B₀ = 3.025M

The concentration of the reactant B after one half-life = B₀/2 = 1.512 M

Learn more about second order reaction, here:

https://brainly.com/question/12446045

#SPJ1

Nitrogen Flouride is an important covalent compound. A diagram showing the arrangement of the valency electrons can be drawn using Lewis Dot Structures.

The basic principle of Lewis Dot Structures is obtaining either a doublet or octet. Nitrogen being a second-period element posses orbitals to accommodate 8 electrons. The electronic arrangement of fluorine can be stabilized by forming a doublet.

Let:

Nitrogen Flouride is pyramidal in existence, with the presence of one lone pair of Nitrogen. The hybridization of 'N' in this covalent molecule is 'sp3'.

Learn more about Lewis Dot Structure:

https://brainly.com/question/10956061

.......................

Molar ratio is widely used in stoichiometry and it represents the number of moles of a compound needed to react with another compound in order to produce a specific amount of product, as the reaction we have in the question:

2 H3PO4 + 3 FeBr2 -> 6 HBr + Fe3(PO4)2

If we have H3PO4 as the focus, we will have the following molar ratios:

2 H3PO4 = 3 FeBr2

2 H3PO4 = 6 HBr

2 H3PO4 = 1 Fe3(PO4)2

These are the specific amounts of reactants needed and products produced in order for the reaction to occur

Therefore the answer is letter B, since 2 H3PO4 = 2 H3PO4 is not a correct molar ratio

The question requires us to calculate the rate of change of NO, given that the rate of change of Cl2 is -0.0500 M/s.

The balanced chemical reaction provided is:

From the stochiometry of the reaction we can say that Δ[NO] = 2/1 Δ[Cl2], thus we can calculate the rate of change of NO as:

Therefore, the rate of change of NO is -0.100 M/s.

20.23 mL is the volume of 0.5 moles of methanol, if it has a density of 0.792 g/mL.

Methanol (CH3OH), also known as methyl alcohol, wood alcohol, or wood spirit, is the most basic of a large group of organic compounds known as alcohols. It is made up of a methyl group (CH3) connected to a hydroxy group (OH).

The destructive distillation of wood once produced methanol. The direct combining of hydrogen and carbon monoxide gas in the presence of a catalyst is the foundation of the modern method for making methanol. Syngas, a blend of carbon monoxide and hydrogen produced from biomass, is being used more frequently to create methanol.

The formula for density is

Density = mass/volume

Here, density is given that is 0.792 g/ml

mass is 0.5 moles which is equal to 16.02g      (substance mass conversion)

Now we need to find volume that is

V = mass/density

V =  16.02g/0.792 g/mL

V = 20.23 mL

Thus, 20.23 mL is the volume of 0.5 moles of methanol

Learn more about methanol

https://brainly.com/question/17078152

#SPJ9