List three ways the rate of solvation of sodium chloride in water may be
increased

Answers

Answer 1

Answer:

1) Increasing temperature

2) Stirring

3) Increasing surface area  of salt by grinding it


Related Questions

What is in period 6 group 8

Answers

Answer:

Osmium

Explanation:

If you take a look at the attached image of a periodic table below, you will see that the element in the 6th period and 8th group is Osmium. Hope this helps!

Two samples of the same rainwater are tested using two indicators at an environrnental lab. The first indicator, Methyl Orange, reveals a distinct yellow color when added to the sample. The second indicator, Litmus, turns red when placed in contact with the water sample.

Required:
a. Identify a possible pH value for the rainwater.
b. Explain, in terms of hydronium ions and hydroxide ion concentrations, the pH value of the rainwater.

Answers

Answer:

A. The pH value of rainwater is acidic about 4.4

B. The molar concentrations of the Hydronium ions are more than that of the hydroxide ions. That is why the rainwater is acidic with a pH of less than 7

Explanation:

A. Methyl orange is an acid indicator that is used to detect acidic solutions which have pH values that fall within the range of about 4.4 to 7.  The distinct yellow colour change that was shown by the methyl orange as it was added to the water shows that the pH value is acidic, with a value above 4.4. (it has to be like this before methyl orange changes to  yellow colour)

B. The Hydronium ( H30+) ion concentrations and the hydroxide (OH-) ion concentrations are used to measure the pH values of substances.

We can tell that the Hydronium ( H30+) ion concentrations are more than the hydroxide (OH-) ion concentrations in the sample of rainwater tested. This can be detected from the colour change that both the methyl orange and the litmus paper gave. The indicators showed that the rainwater solution was indeed acidic. Hence, the pH value will be less than 7, but greater than 4.4.

Round off the following measurement to three significant digits: 29.950g

Answers

Answer:

30.0 g.

Explanation:

Hello,

In this case, for us to round the given number off to three significant figures, we firstly realize it has initially five significant figures. Thus, cutting at the third digit, which is the second nine, we will have 29.9 g, nonetheless, as a five is after such nine, we should round the nine to ten, so the result is 30.0 g.

Best regards.

A 25.0 mL solution of quinine was titrated with 1.00 M hydrochloric acid, HCl. It was found that the solution contained 0.125 moles of quinine. What was the pH of the solution after 50.00 mL of the HCl solution were added

Answers

Answer:

pH = 9.08

Explanation:

Quinine, C₂₀H₂₄O₂N₂, Q, is a weak base that, in water, has as equilibrium:

Q + H₂O ⇄ QH⁺ + OH⁻

Where pKb is 5.10

Using H-H equation for weak bases:

pOH = pKb + log₁₀ [QH⁺] / [Q]

The reaction of quinine with HCl is:

Q + HCl → QH⁺ + Cl⁻

Initial moles of quinine are 0.125 moles and moles added of HCl are:

0.05000L × (1.00mol / L) = 0.05000moles.

That means after the addition of 50.00mL of the HCl solution, moles of Q and QH⁺ are:

Q = 0.125mol - 0.050mol = 0.075 moles

QH⁺ = 0.050 moles

Replacing in H-H equation:

pOH = 5.10 + log₁₀ [0.050] / [0.075]

pOH = 4.92

As pH = 14 - pOJ

pH = 9.08

Suppose that a wave has a period of 0.03 seconds what is its frequency be sure to show the steps for your work

Answers

Answer:

f = 33.34 Hz

Explanation:

A wave has a period of 0.03 seconds. It is required to find the frequency of a wave. The relation between time period and frequency is inverse. The time period of a wave is given by :

T = 1/f, f = frequency of wave

[tex]f=\dfrac{1}{T}\\\\f=\dfrac{1}{0.03}\\\\f=33.34\ Hz[/tex]

So, the frequency of the wave is 33.34 Hz.


Which best explains how heat plays a role in the movement of materials within Earth's interior?

Answers

Answer:

Hot material near the core is less dense and rises, when it cools, it becomes more dense and sinks.

Explanation:

This best explains how heat plays a role in the movement of materials within Earth's interior because it's how convection works. Convection is the circular motion that happens when warmer air or liquid which has faster moving molecules, making it less dense rises, while the cooler air or liquid drops down. Convection currents within the earth move layers of magma, and convection in the ocean creates currents.

Earth’s interior is like a closed chamber, hot material near Earth's surface is more denser and sinks, and when it cools, it becomes less dense and Rises.

What is Convection?

Convection is the process of heat transfer by the bulk movement of molecules within fluids such as gases and liquids. The heat transfer take place from solid to no solid material. like air and water.

As we take example of home. In home heat take nearer the roof and cold air will be nearer to the flour. It is because of hot is less denser then the cold air. Hot air will become less denser and move towords upside. Cold air become denser move towards down.

Similarly, on earth. Nearer to earth hot materials are more dense and sinks. When it cools, it become less dense and rises.

To find more about Heat flow, refer the link below:

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1. ______The force that keeps the nucleons bound inside the nucleus of an atom
A. Strong electrostatic force
B. Strong nuclear force
C. Strong centripetal force
D. Gravitational attraction

2._____The amount of energy needed to split the nucleus into individual protons and neutrons
A. Nuclide transfer energy
B. Nuclear binding energy
C. Mass energy equivalence
D. Nuclear energy
3._______ The difference between the mass of the nucleons and the mass of an Atom
A. Mass of nucleus
B. Mass defect
C. Atomic mass
D. Isotopic mass

Answers

Answer:

1). strong nuclear force 2). nuclear binding energy 3), mass defect

Explanation:

Right on Edge

1. Strong nuclear force the force that keeps the nucleons bound inside the nucleus of an atom.

2. Nuclear binding energy the amount of energy needed to split the nucleus into individual protons and neutrons.

3. Mass defect the difference between the mass of the nucleons and the mass of an Atom.

What is strong nuclear force ?

The term strong nuclear force is defined as the force that binds protons and neutrons together. It also binds them all together in a nucleus and is responsible for the energy released in nuclear reactions.

The examples of strong nuclear force are the force that hold protons and neutrons in nuclei of atoms. The elements' greater than the hydrogen atom. The fusion of hydrogen into helium in the sun's core.

Thus, 1. option B, 2. option B and 3. option B is correct.

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One of the radioactive isotopes used in chemical and medical research is sulfur-35, which has a half-life of 87 days. How long would it take for 0.25 g to remain of a 1.00 g sample of sulfur-35

Answers

Answer:

Time taken = 174 days

Explanation:

Half life is the time take for a subsrtance taken to decay to half of it's origial or initial concentration.

In this probel, the haf life is 87 days, this means that after evry 87 days, the concentration or mass of sulfur-35 decreases by half.

If the starting mass is 1.00g, then we have;

1.00g --> 0.5g (First Half life)

0.5g --> 0.25g (Second half life)

This means that sulphur-335 would undergo two half lives for 0.25g to remain.

Total time taken = Number of half lives  * Half life

Time taken = 2 * 87

Time taken = 174 days

Given the equation:
н
H
H
H
H H H H H H
1
H H
7
C=C
/
H H
+
+
C=C
...
... -
C=C
/
Н.
с C-C-...
|
TI
H H H H H H
I-O-I
I-O-I
1
Н
H
н
Which type of reaction is represented by this equation?
1.
combustion
2.
esterification
3.
polymerization
4
substitution
Submit Answer

Answers

Answer:

The type of reaction is Polymerization

Answer:

combustion?

Explanation:

Yo, like what is that question.

The boiling point of ethanol is 78.40°C. A student conducts an
experiment and finds a boiling point of 75.70°C. How far off
from the accepted value was the student's result?
Error = °C

Answers

Answer:

2.7 °C

Explanation:

78.4-75.7=2.7

The student's result is 2.7° C less than the expected result.

We have a student conducting an experiment to find the boiling point of ethanol.

We have to determine how far off from the accepted value is the student's result.

What is Measurement error ?

Measurement Error (also called Observational Error) is the difference between a measured quantity and its true value.

According to the question, we have -

True value of the boiling point of ethanol [T] = 78.40°C.

Measured value of the boiling point of ethanol [M] = 75.70°C.

The Error (E) in the measurement will be -

E = T - M

E = 78.40° - 75.70° = 2.7° C

Hence, the student's result is 2.7° C less than the expected result.

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How many grams of the salt CaF2 (g) are formed when 15.7 mL of 0.612 M KF reacts with an excess of aqueous calcium bicarbonate (Ca(HCO3)2) via a metathesis reaction?

Answers

Answer:

[tex]m_{CaF_2}0.375gCaF_2[/tex]

Explanation:

Hello,

In this case, for the studied reaction:

[tex]2KF+Ca(HCO_3)_2\rightarrow CaF_2+2KHCO_3[/tex]

Thus, the first step is to compute the reacting moles of potassium fluoride by using its volume and molarity:

[tex]n_{KF}=0.0157L*0.612\frac{mol}{L} =9.61x10^{-3}molKF[/tex]

Then, we apply the 2:1 molar ratio between potassium fluoride and calcium fluoride to compute the produced moles of calcium fluoride:

[tex]n_{CaF_2}=9.61x10^{-3}molKF*\frac{1molCaF_2}{2molKF} =4.80x10^{-3}molCaF_2[/tex]

Finally, by using the molar mass of calcium fluoride (78.07 g/mol) we can compute its produced grams:

[tex]m_{CaF_2}=4.80x10^{-3}molCaF_2*\frac{78.07gCaF_2}{1molCaF_2} \\\\m_{CaF_2}0.375gCaF_2[/tex]

Best regards.

1. Which statement describes the particles of an ideal gas, based on the

kinetic molecular theory?*

O There are attractive forces between the particles.

O The particles move in circular paths.

O The collisions between the particles reduce the total energy of the gas.

О

The volume of the gas particles is negligible compared with the total volume of the

gas.

Answers

Answer:the volume of the gas particles is negligible compared with the total volume of the  gas.--D

Explanation:

According to the Kinetic Molecular Theory for ideal gases, it states that

--Gases are composed of larges  molecules which are in constant random motion  in a straight line

--The volume of the gas particles is negligible compared to the total volume in which the gas is contained.

-----The  Attractive and repulsive forces between gas molecules is insignificant ie There are no interactive forces.

----The collisions of the particles  are perfectly elastic and energyis  being transferred between the particles but the total energy remaining constant

From the  statements of the kinetic Molecular theory of ideal gases, it can be seen that the statement which describes the particles of an ideal gas is option D  which is The volume of the gas particles is negligible compared with the total volume of the  gas--- ---This gives the reason why  gases  can be compressed. Since there are no  inter molecular forces between them. The particles of an  ideal gas will move at the same random motion  resulting to high pressures, compressing the gas and making the volume negligible or insignificant.

Monel metal is a corrosion-resistant copper-nickel alloy used in the electronics industry. A particular alloy with a density of 8.80 g/cm3 and containing 0.090 % Si by mass is used to make a rectangular plate that is 15.0 cm long, 12.5 cm wide, and 3.50 mm thick and has a 2.50-cm-diameter hole drilled through its center such that the height of the hole is 3.50 mm .
The silicon in the plate is a mixture of naturally occurring isotopes. One of the those isotopes is silicon-30, which has an atomic mass of 29.97376 amu. The percent natural abundance, which refers to the atoms of a specific isotope, of silicon-30 is 3.10%.
Part A What is the volume of the plate?Express the volume numerically in cubic centimeters.
Part B How many silicon-30 atoms are found in this plate?
Express your answer numerically using two significant figures.

Answers

Answer:

Based on the given question, the dimensions of the plate is 15 cm in length, 12.5 cm in width, and 3.50 mm in thickness (0.350 cm). Now the volume of the plate will be,  

V = 15 cm × 12.5 cm × 0.350 cm = 65.62 cm³

A hole of diameter 2.50 cm is drilled through the center of the plate, at the height of 3.50 mm or 0.350 cm. Now the volume of the hole is π(r)²h,  

= 22/7 × (1.25 cm)² × 0.350 cm = 1.72 cm³

Thus, the volume of the plate will be determined by subtracting the volume of plate with the volume of hole, which will be,  

65.62 cm³ - 1.72 cm³ = 63.9 cm³

The density of the alloy is 8.80 g/cm³, therefore, the mass of the alloy can be determined by using the formula, mass = density * volume  

mass = 8.80 g/cm³ × 63.9 cm³ = 562.32 grams

Of the total alloy, 0.090 percent is Si, that is,  

(0.090/100) × 562.32 g = 0.506 grams of Si

The natural abundance of the element is not determined by mass but by the number of atoms it possess. For this Avogadro's number and atomic mass of Si is used. Now the number of atoms of Si present is,  

(0.506 g) (1 mol/28.0855 g) (6.023 × 10²³ atoms /mol) = 1.08 × 10²² Si atoms

Of these Si atoms, 3.10 percent are Si-30 so,  

= (3.10 / 100) × (1.08 × 10²² atoms) / 1000 = 3.34 × 10²⁰ atoms of Si-30. or 3.4 × 10²⁰ atoms

RUIGA GIRLS
CHEMISTRY FORM 3. 23/06/2020
MR. GICHURU
IZ
1
Narne the elements present in
Common salt
(2 miks)
Hydrated copper (11) Sulphate.
(2 ks)
Sulphuric (VI) acid,
2 Why is a reaction between zinc metal and Nitric acid not suitable for preparing
hydrogen gae in the laboratory
(2 mi)
(1 m)
3.
What is relative atomic mass?
b)
Define 'isotopes
c)Determine the relative atomic mass of element K whose isotople misure occur in
the proportione:
(2 marks)​

Answers

1)
Common salt= sodium, chlorine
Hydrated copper sulfate= copper, sulfur, water
Sulphuric acid=hydrogen, sulfur, oxygen
2)
Idfk
3)
a)Relative atomic mass is the average mass of an elements atoms(total number of protons and neutrons)
b)An isotope is a form of an element that has the same number of protons but different number of neutrons
c)idfk
Btw ur teachers name is hot

Propane (C3H8) is widely used in liquid form as a fuel for barbecue grills and camp stoves. For 67.7 g of propane, determine the following.(a) Calculate the moles of compound.mol(b) Calculate the grams of carbon.g

Answers

Answer:

A. 1.54 mole.

B. 55.39g of carbon

Explanation:

A. Determination of the number of mole in 67.7g of C3H8.

Mass of C3H8 = 67.7g

Molar mass of C3H8 = (3x12) + (8x1) = 44g/mol

Number of mole of C3H8 =..?

Number of mole = Mass/Molar Mass

Number of mole of C3H8 = 67.7/44

Number of mole of C3H8 = 1.54 mole

B. Determination of the mass of carbon in the compound.

This is illustrated below:

The mass of C in compound can be obtained as follow:

=> 3C/C3H8 x 67. 7

=> 3x12 / 44 x 67.7

=> 36/44 x 67.7

=> 55.39g

Therefore, 55.39g of carbon is present in the compound.

If the Moon rises at 7 P.M. on a particular day, then approximately what time will it rise six days later?

Answers

Answer:

below

Explanation:

28th 10;24 am

If the Moon rises at 7 P.M. on a particular day, then approximately what time will it rise six days later at 12A.M.

How much time changes between Moon rises from one day to the next?

This movement is from the Moon's orbit, which takes 27 days, 7 hours and 43 minutes to go full circle. It causes the Moon to move 12–13 degrees east every day. This shift means Earth has to rotate a little longer to bring the Moon into view, which is why moonrise is about 50 minutes later each day.

So knowing that moonrise is about 50 minutes later each day, we have:

[tex]7+50 minutes = 7:50\\8:40\\9:30\\10:20\\11:10\\12:00 A.M[/tex]

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Compare the conjugate bases of these three acids. Acid 1: hypochlorous acid , HClO Acid 2: phosphoric acid , H3PO4 Acid 3: hydrogen sulfide , HS- What is the formula for the weakest conjugate base ?

Answers

Answer:

The weakest conjugate is HClO-.

Explanation:

As a general rule, the stronger the Bronsted-Lowry acid, the weaker its conjugate base, and vice versa.  

Acid 1: HClO is a strong acid, hence its conjugate base would be weak

Acid 2: H3PO4 is a weak acid, hence its conjugate base would be strong

Acid 3: hydrogen sulphide is also a moderately weak acid with a moderately strong conjugate base.

In order of increasing strengths:

HClO < H2S < H3PO4

what happens when you combine Mg2 and NO3

Answers

Answer: they blow up

Explanation: add them together and they will blow up

Answer:

Magnesium nitrate Reactions

Magnesium nitrate has a high affinity towards water. Therefore, heating it results to decompose into magnesium oxide, nitrogen oxides, and oxygen. 2 Mg(NO3)2 → 2 MgO + 4 NO2 + O2.

If a solution containing 23.81 g of lead(II) acetate is allowed to react completely with a solution containing 7.410 g of sodium sulfate, how many grams of solid precipitate will be formed g

Answers

Answer:

The correct answer is 15.80 grams.

Explanation:

The reaction taking place in the given question,  

Pb(CH₃COO)₂ + Na₂SO₄ ⇒ PbSO₄ + 2NaCH₃COO

The number of moles can be calculated by using the formula,  

n = weight / molecular mass

Based on the given question, the weight of lead (II) acetate is 23.81 grams and the weight of sodium sulfate is 7.410 grams.  

The number of moles of Pb(CH₃COO)₂ is,  

n = 23.81 g / 325.29 g/mol = 0.0732 moles

The number of moles of Na₂SO₄ is,  

n = 7.410 g / 142.04 g/mol = 0.0521 moles

As one mole of lead (II) acetate needs one mole of sodium sulfate. Therefore, 0.0732 moles of lead (II) acetate needs 0.0732 moles of sodium sulfate.  

However, as sodium sulfate is less, that is, 0.0521, therefore, Na₂SO₄ is a limiting reactant.  

One mole of sodium sulfate produces one mole of PbSO₄. So, 0.0521 moles of Na₂SO₄ produces 0.0521 moles of PbSO₄.  

Now the mass of PbSO₄ is,  

mass = moles × molecular mass

mass = 0.0521 × 303.26 g/mol

mass = 15.80 grams.  

How many moles of H2 are needed to produce 34.8 moles of NH3?

Answers

2 i hope this helps

:)✨✨✨✨✨✨

A blood sample is left on a phlebotomy tray for 4 hours before it is delivered to the laboratory. Which group of tests could be performed:

Answers

can you put a picture for reference?


Explain, in terms of charge distribution, why a molecule of carbon tetrachloride is a nonpolar molecule.​

Answers

Answer:

Explanation:

The covalent bond is the chemical bond between atoms where electrons are shared, forming a molecule. Covalent bonds are established between non-metallic elements, such as hydrogen H, oxygen O and chlorine Cl. These elements have many electrons in their outermost level (valence electrons) and have a tendency to gain electrons to acquire the stability of the electronic structure of noble gas.

The covalent bond between two atoms can be polar or nonpolar. If the atoms are equal, the bond will be nonpolar (since no atom attracts electrons more strongly). But, if the atoms are different, the bond will be polarized towards the most electronegative atom, because it will be the atom that attracts the electron pair with more force. Then it will be polar.

It can occur in a molecule that the bonds are polar and the molecule is nonpolar. This occurs because of the geometry of the molecule, which causes them to cancel the different equal polar bonds of the molecule.

In carbon tetrachloride the bonds are polar, but the tetrahedral geometry of the molecule causes all four dipoles to cancel out and the molecule to be apolar.

The carbon tetrachloride s CCL4 is a carbon molecule and four chloride molecule's. The carbon tetrachloride is a nonpolar, as the dipole movement of the molecules ae evenly spaced around the central carbon atom.

As polarity is a result of the geometric sum of the bond dipoles. The bond has separate charges. It's nonpolar because the charge is symmetrically distributed.

Hence the carbon tetrachloride happens to be a nonpolar molecular.

Learn more about the in terms of charge distribution, why a molecule.

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2 FONS
How does the electric force between two charged particles change if the
distance between them is increased by a factor of 22
A. It increases by a factor of 4.
B. It increases by a factor of 2.
C. It decreases by a factor of 4
O
D. It decreases by a factor of 2.
SUB

Answers

Answer:

C. It decreases by a factor of 4

Explanation:

F1 = kq1*q2/r²

F2 = kq1*q2/(2r)² = kq1*q2/(4r²) = kq1*q2/(r²*4)  = F1/4

A sample of 6.022 x 1023 particles of gas has a volume of 22.4 L at 0°C and a pressure of 1.000 atm. Although it may seem silly to contemplate, what volume would 1 particle of gas occupy?



pv=nRT

Answers

Answer:

1 particle of the gas would occupy a volume of 3.718*10⁻²³L

Explanation:

Hello,

1. The sample has a particle of 6.022×10²²particles

2. Volume of the sample = 22.4L

3. Temperature of the sample = 0°C = (0 +273.15)K = 273.15K

4. Pressure of the sample = 1.0atm

What volume would 1 particle of the gas occupy?

But we remember that 1 mole of any substance = 6.022×10²² molecules or particles or atoms

What would be the number of moles for 1 particule?

1 mole = 6.022×10²² particles

X moles = 1 particle

X = (1 × 1) / 6.022×10²² particles

X = 1.66×10⁻²⁴ moles

Therefore, 1 particle contains 1.66×10⁻²⁴ moles

Since we know our number of moles, we can proceed to use ideal gas equation,

Ideal gas equation holds for all ideal gas and is defined as

PV = nRT

P = pressure of the ideal gas

V = volume the gas occupies

n = number of moles of the gas

R = ideal gas constant = 0.082 L.atm / mol.K

T = temperature of the gas

PV = nRT

Solving for V,

V = nRT/ P

We can now plug in our values into the above

equation.

V = (1.66*10⁻²⁴ × 0.082 × 273.15) / 1

V = 3.718*10⁻²³L

Therefore, 1 particule of the gas would occupy a volume of 3.718*10⁻²³L.

what is the name of the liquid in the clinical thermometer​

Answers

Answer:I suppose it is mercury...

Explanation:

I don't say u must have to mark my ans as brainliest but if it has really helped u plz don't forget to thnk me...

The answer is mercury

The solubility of cadmium oxalate, , in 0.150 M ammonia is mol/L. What is the oxalate ion concentration in the saturated solution? If the solubility product constant for cadmium oxalate is , what must be the cadmium ion concentration in the solution? Now, calculate the formation constant for the complex ion

Answers

Answer:

[Cd²⁺] = 2.459x10⁻⁶M

Kf = 9.96x10⁶

Explanation:

Solubility of CdC₂O₄ is 6.1x10⁻³M and ksp is 1.5x10⁻⁸

The ksp of CdC₂O₄ is:

CdC₂O₄(s) ⇄ Cd²⁺(aq) + C₂O₄²⁻(aq)

ksp = [Cd²⁺] [C₂O₄²⁻] = 1.5x10⁻⁸

As solubility is 6.1x10⁻³M, concentration of C₂O₄²⁻ ions is 6.1x10⁻³M. Replacing:

[Cd²⁺] = 1.5x10⁻⁸ / [6.1x10⁻³M]

[Cd²⁺] = 2.459x10⁻⁶M

All Cd²⁺ in solution is 6.1x10⁻³M and exist as Cd²⁺ and as Cd(NH₃)₄²⁺. That means concentration of Cd(NH₃)₄²⁺ is:

[Cd(NH₃)₄²⁺] + [Cd²⁺] = 6.1x10⁻³M

[Cd(NH₃)₄²⁺] = 6.1x10⁻³M - 2.459x10⁻⁶M = 6.098x10⁻³M

[Cd(NH₃)₄²⁺] = 6.098x10⁻³M

In the same way, the whole concentration of NH₃ in solution is 0.150M, as you have 4ₓ6.098x10⁻³M = 0.024M of NH₃ producing the complex, the concentration of the free NH₃ is:

[0.150M] = [NH₃] + 0.024M

0.1256M = [NH₃]

The equilibrium of the complex formation is:

Cd²⁺ + 4 NH₃ → Cd(NH₃)₄²⁺

The kf, formation constant, is defined as:

Kf = [Cd(NH₃)₄²⁺] / [Cd²⁺] [NH₃]⁴

Replacing:

Kf = [6.098x10⁻³M] / [2.459x10⁻⁶M] [0.1256M]⁴

Kf = 9.96x10⁶

The decay of a radioactive material is monitored using a Geiger counter. At the start, the count rate is 2000 decays/minute. Four hours later the decay rate is 500 counts/min. What is the half-life of the material?

Answers

Answer:

The half-life of the material is 2 years

Explanation:

Given;

initial count rate = 2000 decays/minute

final count rate =  500 counts/min

decay time = Four hours

To determine the half life of the material; we create a simple decay table that matches the decay time and count rates.

time (years)                     count rate

0                                    2000 decays/minute

2                                     1000 decays/minute

4                                     500 decays/minute

Half life is the time intervals = 2 years

Also using a formula;

[tex]N = \frac{N_o}{(t/2)^2} \\\\N_o-is \ the \ initial \ count\ rate\\\\N-is \ the \ final \ count\ rate\\\\t/_2 - is \ the\ half\ life \\\\N = \frac{N_o}{(t/2)^2} \\\\500 = \frac{2000}{(t/2)^2}\\\\(t/_2)^2 = \frac{2000}{500} \\\\(t/_2)^2 = 4\\\\t/_2 = \sqrt{4} \\\\t/_2 = 2 \ years[/tex]

Therefore, the half-life of the material is 2 years

                                                               

Glycine, C2H5O2N, is important for biological energy. The combustion reaction of glycine is given by the equation 4C2H5O2N(s) + 9O2(g) → 8CO2(g) + 10H2O(l) + 2N2(g) ΔH°rxn = –3857 kJ/mol Given that ΔH°f[CO2(g)] = –393.5 kJ/mol and ΔH°f[H2O(l)] = –285.8 kJ/mol, calculate the enthalpy of formation of glycine.

Answers

Answer:

ΔH°f C₂H₅O₂N(s)  = -537.2kJ

Explanation:

Based on the reaction:

4 C₂H₅O₂N(s) + 9O₂(g) → 8CO₂(g) + 10H₂O(l) + 2N₂(g)

ΔHrxn = ΔH°f products - ΔH°f reactants.

As:

ΔH°fO₂(g) = 0

ΔH°fCO₂(g) = -393.5kJ/mol

ΔH°fH₂O(l) = -285.8kJ/mol

ΔH°fN₂(g) = 0

The ΔHrxn is:

ΔHrxn = (8×-393.5kJ/mol + 10×-285.8kJ/mol) - (4×ΔH°fC₂H₅O₂N(s)) = -3857kJ/mol

-6006kJ/mol - (4×ΔH°fC₂H₅O₂N(s)) = -3857kJ/mol

-4×ΔH°fC₂H₅O₂N(s) = 2149kJ/mol

ΔH°fC₂H₅O₂N(s) = 2149kJ/mol / -4

ΔH°f C₂H₅O₂N(s)  = -537.2kJ

How is the mass of the atom calculated?

by adding the number of protons and electrons
by adding the number of protons and neutrons
by subtracting the number of electrons from the number of protons
by adding the number of neutrons and electrons

Answers

The mass of the atom is calculated by adding the number of protons and neutrons .

What do you mean by atomic mass of an element ?

The total mass of one atom of an element is defined as its atomic mass. The atomic mass is taken as the mass of protons and neutrons in an atom.

1 a m u = 1.66 ×10⁻²⁴g

To calculate the atomic mass of an element -:

The atomic mass of the single atom can be calculated by adding the total number of protons and the total number of neutrons of that particular atom.

Atomic mass Number = Number of protons + number of neutrons

Hence ,in this way the atomic mass is calculated of an atom .

Learn more about atomic mass ,here:

https://brainly.com/question/17067547

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A compound has an empirical formula of CHN. What is the molecular formula, if it’s molar mass is 135.13 g/mol? (C=12.01 amu, H=1.008 amu, N= 14.01)

Answers

Answer:

well the MF is 224.78 g/mol

Explanation:

just times them all by the molor mass and divide it by 3

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