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According to the Avogadro's number, there are 3.011×10²³ atoms in 0.5 mole of aluminium.

Avogadro's number is defined as a proportionality factor which relates number of constituent particles with the amount of substance which is present in the sample.

It has a SI unit of reciprocal mole whose numeric value is expressed in reciprocal mole which is a dimensionless number and is called as Avogadro's constant.It relates the volume of a substance with it's average volume occupied by one of it's particles .

According to the definitions, Avogadro's number depend on determined value of mass of one atom of those elements.It bridges the gap between macroscopic and microscopic world by relating amount of substance with number of particles.

Number of atoms can be calculated using Avogadro's number as follows: mass/molar mass×Avogadro's number, on substituting values in formula, 0.5×6.023×10²³=3.011×10²³ atoms.

Thus, there are 3.011×10²³ atoms in 0.5 mole of aluminium.

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Answer:

[tex]M_{acid}=0.563M[/tex]

Explanation:

Hello there!

In this case, given the neutralization of the acetic acid as a weak one with sodium hydroxide as a strong base, we can see how the moles of the both of them are the same at the equivalence point; thus, it is possible to write:

[tex]M_{acid}V_{acid}=M_{base}V_{base}[/tex]

Thus, we solve for the molarity of the acid to obtain:

[tex]M_{acid}=\frac{M_{base}V_{base}}{V_{acid}} \\\\ M_{acid}=\frac{33.98mL*0.1656M}{10.0mL}\\\\ M_{acid}=0.563M[/tex]

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Answer:

C. When melted rock solidifies.

Answer:

endormic

Explanation:

It occurs at a temperature and pressures below a substance's triple point on its phase diagram, which corresponds to the lowest pressure at which the substance can exist as a liquid

Answer:

D. Entropy is the measure of randomness

Explanation:

I got it right so I don't know if it's going to be right for you. All questions/answers are not the same but since I personally got it right then I wanted to help you out! I apologize if I'm late/wrong! God bless you guys!

Answer:

Entropy is a measure of randomness.

Explanation:

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Answer: 5

Explanation:

I hope this helped!

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Answer:

benzoic acid: pka = 4.19

Explanation:

actual yield of ethanol = 305.0g

molar mass of sucrose = 342g

molar mass of ethanol  =46g

mass of sucrose = 665g

mole of sucrose = mass / molar mass = 665/342

mole of sucrose =1.9 mole

sucrose :  C2H5OH

       1      :  4

     1.9     : 1.9x4 =7.6 mole of C2H5OH are formed

mass (therotical yield ) of C2H5OH= mole x mass

mass (therotical yield ) of C2H5OH= 7.6 x 46 = 349.6g

percent yields of ethanol =  actual /therotical x100

=305/349.6x100 = 87.24 %

Answer:

0.06moles/litres

Explanation:

molarity = no of moles / volume in litres = 3.00*10^-2/(450/1000)=0.06 moles/litres

Answer:

0.07mol/dm^3

Explanation:

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Answer:

pH= 1.70

Explanation:

I      4.988        0     0

C     -x             +x     +x

E     4.988 -x    x       x

8.0 x 10^-5 = X^2/ 4.988 - x

(since the X value is so small, round 4.988-x to 4.988 because X is close to zero)

8.0 x 10^-5 = x^2/4.988

x4.988           x4.988

4.0 x 10^-4 = x^2

x = .0199

pH=-log[.0199] = 1.70

Answer:

Mount, Charger, Colt, Pony, and Folt

Explanation:

Answer:

A stallion or a mare

Explanation:

Answer:

Attached below

Explanation:

(a) 3-Methylcyclobutene

(b) 1-Methylcyclopentene

(c) 2,3-Dimethyl-2-pentene

(d) (Z)-3-Hexene  

(e) (E)-2-Pentene

(f) 3,3,3-Tribromopropene

(g) (Z,4R)-4-Methyl-2-hexene

(h) (E,4S )-4-Chloro-2-pentene

(i) (Z)-1-Cyclopropyl-1-pentene

(j) 5-Cyclobutyl-1-pentene

(k) (R)-4-Chloro-2-pentyne

(l) (E)-4-Methylhex-4-en-1-yne

The structural formula of a compound ( chemical ) is the representation of the molecular structure of the compounds ( i.e. it shows how the atoms in the compound is arranged, also the chemical bonding within the molecules are represented as well.

Explanation:

heyyyyyyyyy how are you sure

Answer:

46 g

Explanation:

First we convert 1.2 x 10²⁴ atoms of sodium into moles, using Avogadro's number:

Then we convert 2.0 moles of sodium into grams, using sodium's molar mass:

Thus, there are 46 grams in 1.2x10²⁴ atoms of sodium.

Answer: first you have to calculate the amount ionized. We will say it is x mol / L

then % ionization = (amount ionized / initial concentration) * 100%

x can be calculated using an ice chart

HC3H5O2           -----> H+    + C3H5O2-

Initial HC3H5O2 = 0.250  

change              = -x

equilibrium         = 0.250 - x

initial H+            = 0

change              = +x

equilibrium         = x

C3H5O2- initial   = 0

change              = +x

equilibrium         = x

Ka         = [H=][C3H5O2-] / HC3H5O2]

 1.3 * 10 ^ -5    = [x][x] / (0.250 - x)  

So 1.3 * 10 ^ -5 * (0.250 - x)   = x ^ 2  

     3.25 * 10^ -6 - (1.3 * 10^-5)x = x^2   now this is a quadratic equation and you have to rearrange it and solve for x

x^2 + 1.3 * 10^-5)x - 3.25 * 10^ -6 = 0

use the equation x = {-b (+ or -)[b^2 - 4.a.c] ^ 1/2} / 2a

you should get x = 1.80 * 10 ^ -3 or x = -1.80* 10^-3

but x can not be negative..

so x = 1.80 * 10 ^ -3

so percent ionization = (1.80 * 10 ^ -3 / 0.250) * 100%

                               =0.72 %

the other way which is more easier is  

assuming that x is very small and therefore 0.250 - x is approximately equals to 0.250  

then 1.3 * 10^-5 = x^2 / 0.250

so x^2    = 1.3 * 10^-5 * 0.250

        x   = 1.80 * 10 ^-3

then percent ionization is = (1.80 * 10 ^ -3 / 0.250) * 100%

                               =0.72 %

if the percent ionization is > 5 % you can not do that approximation. in such a case you have to solve the quadratic equation. that is why I showed both methods.

now you can do the parts b and c

b answer : percent ionization = 1.27 %  

c answer : 2.54%

good luck

Answer:

Jet ğıpep2pep2p2pp3oroe88r82

Answer:

Where?

Explanation:

Answer:  An electrochemical cell that produces electricity from a spontaneous oxidation-reduction reaction

Explanation:

Galvanic cell is a device which is used for the conversion of the chemical energy produced in a redox reaction into the electrical energy.

Galvanic cell consists of two half cells known as anode and cathode. Oxidation takes place at anode and reduction takes place at cathode. The two half cells are connected by a salt bridge which contains an electrolyte which maintains the electrical neutrality.

Answer:

The reactions that might ensue are

Cl[tex]_{2}[/tex](g) + H[tex]_{2}[/tex]O ----------  > HOCl + HCl

 HOCl -------- > [tex]H^+[/tex](aq) + O[tex]CI^-[/tex](aq)

Cl2(g) + [tex]OH^-[/tex](aq) ----- > O[tex]CI^-[/tex](aq) + HCl

Explanation:

The Disinfectant Given is

CI2 (g) at PH 9

Determine the chemical reactions that might ensue

due to the High concentration of [tex]H^{+} (aq)[/tex] the formation of [tex]OCI^-[/tex](aq) will be better and this will decrease the power of the disinfectant.

Hence the chemical reactions that might ensue can be represented below as :

Cl[tex]_{2}[/tex](g) + H[tex]_{2}[/tex]O ----------  > HOCl + HCl

            HOCl -------- > [tex]H^+[/tex](aq) + O[tex]CI^-[/tex](aq)

Cl2(g) + [tex]OH^-[/tex](aq) ----- > O[tex]CI^-[/tex](aq) + HCl

Answer: 2.00 mol

Explanation:

The balanced chemical equation is:

[tex]2H_2(g)+O_2(g)\rightarrow 2H_2O(g)[/tex]  

According to stoichiometry :

2.00 moles of [tex]H_2[/tex] require = 1.00 moles of [tex]O_2[/tex]

Thus 2.00 moles of [tex]H_2[/tex] will require=[tex]\frac{1}{2}\times 2.00=1.00moles[/tex]  of [tex]O_2[/tex]

Thus both will act as limiting reagents and will be fully consumed.

2.00 moles of [tex]H_2[/tex] will form = 2 moles of [tex]H_2O[/tex]

Thus 2.00 moles of [tex]H_2[/tex] will form = [tex]\frac{2}{2}\times 2.00=2.00moles[/tex]  of [tex]H_2O[/tex]

  Thus 2.00 moles of [tex]H_2O[/tex] will be produced from the given masses of both reactants.

Answer: 4.4 x 10^-7

Explanation:

0.000066 x 0.0000066 / 0.01

= 4.4 x 10^-7

Answer:

b

Explanation:

During a running (dynamic) compression test at idle, a good engine should produce PSI between 60 to 90​. The correct answer is option D.

A running compression test is a diagnostic test that measures the compression pressure of an engine while it is running.

Therefore, in general, a good engine should produce compression pressure between 60 to 90​ PSI during a running compression test at idle. Option D is the correct answer.

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Answer:

The gas is decreasing at a rate of 50 cubic centimeters per minute.

Explanation:

The Boyle's Law is represented by the following expression:

[tex]P\cdot V = k[/tex] (1)

Where:

[tex]P[/tex] - Pressure, in kilopascals.

[tex]V[/tex] - Volume, in cubic centimeters.

[tex]k[/tex] - Proportionality constant, in kilopascal-cubic centimeters.

By definitions of rate of change and implicit differentiation, we derive the following differential equation:

[tex]\dot P \cdot V + P\cdot \dot V = 0[/tex] (2)

Where:

[tex]\dot P[/tex] - Rate of change of the pressure, in kilopascals per minute.

[tex]\dot V[/tex] - Rate of change of the volume, in cubic centimeters per minute.

Then, we clear the rate of change of the volume within (2):

[tex]P\cdot \dot V = -\dot P\cdot V[/tex]

[tex]\dot V = -\left(\frac{\dot P}{P} \right) \cdot V[/tex]

If we know that [tex]P = 180\,kPa[/tex], [tex]\dot P = 30\,\frac{kPa}{min}[/tex] and [tex]V = 300\,cm^{3}[/tex], then the rate of change of the volume is:

[tex]\dot V = -\left(\frac{\dot P}{P} \right) \cdot V[/tex]

[tex]\dot V = -50\,\frac{cm^{3}}{min}[/tex]

The gas is decreasing at a rate of 50 cubic centimeters per minute.

Answer:

I did this TGA got it right it is bottom left corner

Explanation:

Answer:

2.64 M

Explanation:

Use the dilution equation M1V1 = M2V2, where:

M1 = 12.0 M HCl

V1 = 220 mL HCl

M2 = ?

V2 = 1000 mL HCl

(12.0 M HCl)(220 mL HCl) = M2(1000 mL HCl)

M2 = 2.64 M HCl

Answer:

The forest products industry plays a major role in the Swedish economy, and accounts for between nine and 12 percent of Swedish industry's total employment, exports, sales and added value. It includes companies within the pulp and paper industry, as well as the wood-mechanical industry.

Answer: Thus 81 grams of Au is 9210 ml

Explanation:

According to avogadro's law, 1 mole of every substance occupies 22.4 L at STP and contains avogadro's number [tex]6.023\times 10^{23}[/tex] of particles.

To calculate the moles, we use the equation:

[tex]\text{Number of moles}=\frac{\text{Given mass}}{\text {Molar mass}}[/tex]

[tex]\text{moles of Au}=\frac{81g}{196.96g/mol}=0.411moles[/tex]

1 mole of Au occupies = 22.4 L

Thus 0.411 moles of Au occupy = [tex]\frac{22.4}{1}\times 0.411=9.21L=9210ml[/tex]

81 grams of Au is 9210 ml