Calculate the molality of a 5.51 M ethanol (C2H5OH) solution whose density is 0.9349 g/mL

The answer is [OH⁻] = 1 x 10⁻⁴.

[OH⁻] = H₂O ÷ [H₃O⁺]

[OH⁻] = 1 x 10⁻¹⁴ / 1 x 10⁻¹⁰

[OH⁻] = 10⁻⁴

Answer:

the half life of reaction is 2 hours which is consist half life of consist in the first order reaction has the order reaction is one

Considering the definition of empirical and molecular formula, the pair C₆H₆ and C₃H₃ shares the same empirical formula.

The empirical formula is the simplest expression to represent a chemical compound, and indicates the elements that are present and the minimum proportion in whole numbers between its atoms. This formula is also known as the “minimum formula”.

That is, the empirical formula is the expression of the simplest ratio between the atoms of a chemical compound and indicates the different elements that make up the molecule and the relationship between them. But it does not indicate the actual formula of the compound.

The molecular formula is the actual formula of the molecule, it tells us the types of atoms and the number of each type that participate in the formation of the molecule.

In this case, the pair C₆H₆ and C₃H₃ shares the same empirical formula. In the first case, the ratio of carbon atoms to hydrogen atoms is 6:6 or 1:1, while in the second case said ratio is 3:3 or 1:1. Therefore, the relationship is the same, so they have the same empirical formula.

In summary, the pair C₆H₆ and C₃H₃ shares the same empirical formula.

Learn more about empirical and molecular formula:

https://brainly.com/question/1363167

https://brainly.com/question/26388921

https://brainly.com/question/11588623

https://brainly.com/question/13058832

#SPJ1

See the attached image.

Answer:

A.) 2,4,5-trimethylhexan-2-ol

B.) 6-bromo-3-ethylhexan-2-one

C.) 3-isoproyl-4-propyloctan-1-al

Explanation:

A.) Since there is an alcohol (-OH) group in the molecule, the name should have the ending -ol. Since the alcohol is on the 2nd carbon, there should be a 2 in front of the -ol. The longest carbon chain contains 6 single-bonded carbons, making this a hexane. There are 3 methyl (-CH₃) groups on the 2nd, 4th, and 5th carbons.

Therefore, the IUPAC name is: 2,4,5-trimethylhexan-2-ol

B.) Since there is a ketone (C=O) group in the molecule, the name should have the ending -one. Since the ketone takes priority, it is on the 2nd carbon. As such, there should be a 2 in front of the -one. The longest carbon chain contains 6 single-bonded carbons, making this a hexane. There is an ethyl (-CH₂CH₃) group on the 3rd carbon and a bromo (-Br) group on the 6th carbon.

Therefore, the IUPAC name is: 6-bromo-3-ethylhexan-2-one

C.) Since there is an aldehyde (HC=O) group in the molecule, the name should have the ending -al. Since the aldehyde is on the 1st carbon, you can add a 1 before the -al (technically not necessary). The longest carbon chain contains 8 single-bonded carbons, making this an octane. There is an isopropyl (-CHCH₃CH₃) group on the 3rd carbon and a propyl (-CH₂CH₂CH₃) on the 4th carbon.

Therefore, the IUPAC name is: 3-isoproyl-4-propyloctan-1-al (or 3-isoproyl-4-propyloctanal)

The number of moles of 210 grams of NaHCO₃ is 2.5 moles.

To calculate the number of moles use the formula

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

Mass of NaHCO₃ = 210 g

Now we have to find the Molar mass of NaHCO₃

= Atomic mass of Na + Atomic mass of H + Atomic mass of C + 3 (Atomic mass of O)

= 23 + 1 + 12 + 3 (16)

= 36 + 48

= 84 g/mol

Now put the value in above formula we get

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

                             = [tex]\frac{210\ g}{84\ g/mol}[/tex]

                             = 2.5 moles

Thus from the above conclusion we can say that The number of moles of 210 grams of NaHCO₃ is 2.5 moles.

Learn more about the Moles here: https://brainly.com/question/15356425

#SPJ1

Answer:

B

Explanation:

Planting trees sequesters CO2

  all of the other choices produce more CO2 in the atmosphere

If a reactant is oxidized, another reactant must be reduced (option D).

Redox reaction also known as oxidation-reduction reaction relates to any reaction in which oxidation and reduction occur simultaneously.

This means that in a redox reaction, electrons are lost and gained at the same time.

The substance that loses electrons in a redox reaction is called reducing agent while the substance that gains electrons in a redox reaction is called oxidizing agent.

Therefore, if a reactant is oxidized, another reactant must be reduced.

Learn more about redox reaction at: https://brainly.com/question/13293425

#SPJ1

Answer:

0.436 ⇒ 0.44

9.000 ⇒ 9.0

Concept:

Significant figures are where each of the digits of a number are used to express it to the required degree of accuracy, starting from the first nonzero digit.

Therefore, in the context of this question, two significant figure means that two digits of numbers are kept, from left to right, starting from the first nonzero digit.

Solve:

0.436 has 3 significant digits in total starting from left to right

Thus, the last digit should be rounded up / down

Since the last digit is 6, it is greater than 5, so it should be rounded up.

Therefore, a rounded 0.436 is [tex]\Large\boxed{0.44}[/tex]

9.000 has 4 significant digits in total starting from left to right

Thus, the last two digits should be rounded up / down

Since the last two digits are 0, it is less than 5, so it should be rounded up (or remained).

Therefore, a rounded 9.000 is [tex]\Large\boxed{9.0}[/tex]

Hope this helps!! :)

Please let me know if you have any questions

Answer:

Δx(m.Δv)=h/4π

here ,

Δv = uncertainty in velocity

10−11×10−27×Δv=6.626×10−34/4×22/7

=5.25×103ms−1

[tex]{ \qquad\qquad\huge\underline{{\sf Answer}}} [/tex]

Here we go ~

According to Heisenberg's uncertainty principle :

[tex]\qquad \sf  \dashrightarrow \: \Delta x \Delta p \geqslant \cfrac{h}{4 \pi} [/tex]

[tex]\qquad \sf  \dashrightarrow \: \Delta x \cdot m \Delta v \geqslant \cfrac{h}{4 \pi}[/tex]

[tex]\qquad \sf  \dashrightarrow \: \Delta v \geqslant \cfrac{h}{4 \pi \cdot m \Delta x}[/tex]

[tex]\qquad \sf  \dashrightarrow \: \Delta v \geqslant \cfrac{6.6 \times 10 {}^{ - 34} }{4 \pi \cdot 10 {}^{ - 27} \times 10 {}^{ - 3} \times 10 {}^{ - 11} }[/tex]

[tex] \textsf{ [ we took } [/tex][tex]{ {10}^{-3} } [/tex][tex] \textsf{because mass of electron is} [/tex][tex] \textsf{ given in grams that need to be converted into kg ]} [/tex]

[tex]\qquad \sf  \dashrightarrow \: \Delta v \geqslant \cfrac{6.6 }{4 \pi } \times \cfrac{10 {}^{ - 34} } {10 {}^{ (- 27 - 3 - 11)} } [/tex]

[tex]\qquad \sf  \dashrightarrow \: \Delta v \geqslant \cfrac{6.6 }{4 \times 3.14 } \times \cfrac{10 {}^{ - 34} } {10 {}^{ - 41} } [/tex]

[tex]\qquad \sf  \dashrightarrow \: \Delta v \geqslant \cfrac{6.6 }{4 \times 3.14 } \times {10 {}^{ 7}}[/tex]

[tex]\qquad \sf  \dashrightarrow \: \Delta v \geqslant \cfrac{6.6 }{12.56 } \times {10 {}^{ 7}}[/tex]

[tex]\qquad \sf  \dashrightarrow \: \Delta v \geqslant0.525\times {10 {}^{ 7}}[/tex]

[tex]\qquad \sf  \dashrightarrow \: \Delta v \geqslant5.25\times {10 {}^{ 6}} \:\:m/s[/tex]

This exercise is related to the subject of Structured Thinking. See the definition of structured thinking below.

The process of developing a structured framework to address an unstructured situation is known as structured thinking.

Structured thinking is a strategy of problem-solving that entails breaking a huge problem into smaller ones in order to tackle the larger problem more quickly and effectively.

Categorizing things and identifying themes are two subjects under structured thinking.

To categorize anything requires:

Identifying themes entails:

Learn more bout structured thinking at;
https://brainly.com/question/27972911
#SPJ1

Answer:

D.) 2.5 moles

Explanation:

To find the moles of H₂, you need to multiply the given value by the mole-to-mole ratio. This ratio consists of the coefficients in front of the relevant molecules. It is important to arrange the ratio in a way that allows for the cancellation of units.

1 Mg + 2 HCl -----> MgCl₂ + 1 H₂
^                                            ^

2.5 moles Mg            1 moles H₂
-----------------------  x  ---------------------  =  2.5 moles H₂
                                   1 mole Mg

B. A student who prefers to study by recalling personal examples that connect to what is being learned, makes lists of ways to use skills in real scenarios (like at work), and starts a discussion with another student to talk about a topic most likely prefers Auditory.

Auditory learning style is a method of learning that involves listening.

Auditory learning means that a student learns most effectively by listening.

In Auditory learning style, students would prefer listening to a lecture over reading a textbook, or hearing the instructions for a project instead of figuring it out hands-on.

Thus, a student who prefers to study by recalling personal examples that connect to what is being learned, makes lists of ways to use skills in real scenarios (like at work), and starts a discussion with another student to talk about a topic most likely prefers Auditory.

Learn more about Auditory here: https://brainly.com/question/27824005

#SPJ1

Answer:

A.) [tex]K_b = \frac{[CH_3NH_3^+][OH^-]}{[CH_3NH_2]}[/tex]

Explanation:

The general Kb expression is:

[tex]K_b = \frac{[HA][OH^-]}{[A^-]}[/tex]

In this equation

-----> Kb = equilibrium constant

-----> [HA] = acid

-----> [A⁻] = base

Since liquids are not included in equilibrium expressions, H₂O should not be present. The products are in the numerator while the reactant are in the denominator. In this reaction, CH₃NH₂ is acting as a base and CH₃NH₃⁺ is acting as an acid.

As such, the expression is:

[tex]K_b = \frac{[CH_3NH_3^+][OH^-]}{[CH_3NH_2]}[/tex]

The identity of a metal that has a mass of 27.0g and a volume of 10.0cm is Aluminium. That is option B.

Molar mass is defined as the mass in grams of one mole of an element. This is measured in grams/mole of that substance.

The metal that is 27.0 g and a volume of 10.0 cm3 is aluminium because aluminium is 27 times heavier than 1/12th of the mass of carbon-12 atom.

Therefore, the identity of a metal that has a mass of 27.0g and a volume of 10.0cm is Aluminium.

Learn more about molar mass here:

https://brainly.com/question/837939

#SPJ1

Answer:

B.) 36.0 grams

Explanation:

To find the mass of water, you need to (1) convert grams H₂ to moles (using the molar mass), then (2) convert moles H₂ to moles H₂O (using mole-to-mole ratio from reaction coefficients), and then (3) convert moles H₂O to grams (using the molar mass). It is important to arrange the conversions in a way that allows for the cancellation of units.

Molar Mass (H₂): 2(1.008 g/mol)

Molar Mass (H₂): 2.016 g/mol

Molar Mass (H₂O): 2(1.008 g/mol) + 15.998 g/mol

Molar Mass (H₂O): 18.014 g/mol

2 H₂ + O₂ -----> 2 H₂O
^                        ^

4.0 g H₂            1 mole             2 moles H₂O           18.014 g
---------------  x  ----------------  x  ------------------------  x  ---------------  = 36 g H₂O
                          2.016 g             2 moles H₂              1 mole

The answer is 6 nitrogen atoms.

The given chemical formula is : 3Zn(NO₃)₂

Let's find the number of nitrogen atoms by opening the bracket.

Hence, there are 6 nitrogen atoms.

22.37 g of chromium(II) nitrate, must be dissolved to prepare 500. mL of a 0.188 M aqueous solution of the salt.

According to the definition, the molar concentration of a substance in a solution is the ratio of the number of the moles to the volume of the solution:

c=n/V.

The number of the moles is related to the mass with the molar mass:

n=m/M;

m=n·M.

Thus, given the volume of the solution of chromium(II) nitrate, its concentration and molar mass is 238.011 g/mol we can calculate the mass of chromium(II) nitrate needed for the preparation :

∴   Cr(NO₃)₃ = cVM

                 = 0.188 M × 0.5 L × 238.011 g/mol

                 = 22.37 g

Therefore, 22.37 g of chromium(II) nitrate, must be dissolved to prepare 500. mL of a 0.188 M aqueous solution of the salt.

Learn more about molar here:

https://brainly.com/question/837939

#SPJ1

The decrease in the freezing point of the solution is −1.86oC.

Now we know that the freezing point depression of a solid is a colligative property of the solution.

Thus we have that;

ΔT = K m i

ΔT = freezing point depression

K = freezing constant

m = molality of the solution

i = Van't Hoff factor

Thus;

molality =  1 mol/1 Kg = 1 m

ΔT = −1.86oC/m * 1 m * 1

ΔT =−1.86oC

Learn  more about freezing point:https://brainly.com/question/3121416

#SPJ1

Answer:

0.116 M

Explanation:

(Step 1)

Calculate the amount of moles using the molarity ratio.

100.0 mL / 1,000 = 0.1000 L

Molarity = moles / volume

0.695 M = moles / 0.1000 L

0.0695 = moles

(Step 2)

Calculate the new molarity using the moles and new volume.

500.0 mL / 1,000 = 0.5000 L

Molarity = moles / volume

Molarity = 0.0695 moles / (0.1000 L + 0.5000 L)

Molarity = 0.0695 moles / (0.6000 L)

Molarity = 0.116 M

Answer:

2.60 L

Explanation:

To find the new volume, you need to use the Combined Gas Law:

[tex]\frac{P_1V_1}{T_1}=\frac{P_2V_2}{T_2}[/tex]

In this equation, "P₁", "V₁", and "T₁" represent the initial pressure, volume, and temperature. "P₂", "V₂", and "T₂" represent the final pressure. volume, and temperature.

At STP, the pressure is 1.0 atm and the temperature is 273 K. Before you can plug the values into the equation, you need to convert pressure from torr to atm and the temperature from Celsius to Kelvin.

P₁ = 720 torr / 760 = 0.947 atm            P₂ = 1.0 atm

V₁ = 3.0 L                                                V₂ = ? L

T₁ = 25 °C + 273 = 298 K                       T₂ = 273 K

[tex]\frac{P_1V_1}{T_1}=\frac{P_2V_2}{T_2}[/tex]                                                  <----- Combined Gas Law

[tex]\frac{(0.947atm)(3.0L)}{298K}=\frac{(1.0atm)V_2}{273K}[/tex]                           <----- Insert values

[tex]\frac{2.84}{298K}=\frac{(1.0atm)V_2}{273K}[/tex]                                          <----- Multiply 0.947 and 3.0

[tex]0.00954=\frac{(1.0atm)V_2}{273K}[/tex]                                      <----- Simplify left side

[tex]2.60={(1.0atm)V_2}[/tex]                                         <----- Multiply both sides by 273

[tex]2.60L=V_2[/tex]                                                    <----- Divide both sides by 1.0

56.4 g of platinum will contain 1.7417 x  [tex]10^{23}[/tex] atoms

According to Avogadro, 1 mole of any substance contains 6.022 x [tex]10^{23}[/tex] atoms of the substance.

The problem is we don't know how many moles of platinum that are present in 56.4 g. Thus, the first thing is to calculate the number of moles of platinum present in 56.4 g of the substance.

This can be achieved by using the formula, mole = mass/molar mass. Keep in mind that the molar weight of platinum is 195 g/mol.

Therefore,

Mole of 56.4 g of platinum = 56.4/195 = 0.2892 moles

If,

1 mole of any substance = 6.022 x [tex]10^{23}[/tex] atoms

Then,

0.2892 moles of platinum = 0.2892 x 6.022 x [tex]10^{23}[/tex] atoms = 1.7417 x  [tex]10^{23}[/tex] atoms

In other words, 56.4 g of platinum will contain 1.7417 x  [tex]10^{23}[/tex] atoms 1.7417 x  [tex]10^{23}[/tex] atoms of the metal.

More on the number of atoms in substances can be found here: https://brainly.com/question/11373631

#SPJ1

0.5376 g is the minimum mass of sodium sulfite that we should add.

Molarity (M) is defined as the number of moles of solute dissolved in 1L of solution. Molarity is also known as Molar concentration. The S.I unit of Molarity is molar (M) or mol/L.

The conversion sequence is

mL solution → L solution →  mol → g

[tex]80\ mL \times \frac{1\ L}{1000\ mL} \times \frac{0.04\ \text{mol Calcium nitrate solution}}{L} \times \frac{168\ \text{Calcium nitrate solution}}{\text{mol Calcium nitrate solution}}[/tex]

= 0.5376 g

Thus from the above conclusion we can say that 0.5376 g is the minimum mass of sodium sulfite that we should add.

Learn more about the Molarity here: https://brainly.com/question/26873446

#SPJ1

Answer:

80.5%

Explanation:

The percent yield is made up of the theoretical yield and actual yield. The theoretical yield is the amount of product produced from the balanced chemical equation and molar masses. The actual yield is the amount of product produced in an experiment.

To find the percent yield, you need to (1) convert grams C₃H₈ to moles C₃H₈ (via molar mass), then (2) convert moles C₃H₈ to moles CO₂ (via mole-to-mole ratio from equation coefficients), then (3) convert moles CO₂ to grams CO₂ (via molar mass), and then (4) calculate the percent yield. It is important to arrange the conversions/ratios in a way that allows for the cancellation of units.

(Steps 1 - 3)

Molar Mass (C₃H₈): 3(12.01 g/mol) + 8(1.01 g/mol)

Molar Mass (C₃H₈): 44.11 g/mol

Molar Mass (CO₂): 12.01 g/mol + 2(16.0 g/mol)

Molar Mass (CO₂): 44.01 g/mol

1 C₃H₈ + 5 O₂ -----> 3 CO₂ + 4 H₂O

296 g C₃H₈           1 mole            3 moles CO₂           44.01 g
-------------------  x  ----------------  x  ----------------------  x  ----------------  =  886 g CO₂
                               44.11 g            1 mole C₃H₈            1 mole

(Step 4)

                                  Actual Yield
Percent Yield  =  ------------------------------  x  100%
                              Theoretical Yield

                                713 g CO₂
Percent Yield  =  ----------------------  x  100%
                                886 g CO₂

Percent Yield  =  80.5%

The environmental conditions of the ocean are:

In our oceans, there are known to be a lot of environmental conditions that are known to often affect the growth, survival and also the productivity of marine organisms. These are the ones listed above.

Note that the increased concentration of chemicals, e.g.  nitrogen and phosphorus is one that can be harmful to marine life.

Hence, The environmental conditions of the ocean are:

Learn more about ocean from

https://brainly.com/question/25154137

#SPJ1

Answer:

Explanation:

Greetings !

The electronic configuration 1s²,2s²,2p⁶,3s²,3p³ represents phosphorus with atomic number 15.

The electron configuration 1s², 2s², 2p⁶, 3s², 3p³ corresponds to the element phosphorus. The first two shells are full, with 2 electrons in each shell. The third shell has 2 electrons in the 3s subshell and 3 electrons in the 3p subshell. Hence option D is correct.

Phosphorus is a chemical element with the symbol P and atomic number 15. It belongs to Group 15 (or Group V) of the periodic table, which is also known as the nitrogen group. Here are some key features and characteristics of phosphorus:

Phosphorus is a non-metal, and at room temperature, it exists in several allotropes. The most common forms are white phosphorus, red phosphorus, and black phosphorus.

White phosphorus is a highly reactive and toxic waxy solid, while red phosphorus is less reactive and is often used in safety matches. Black phosphorus is a semiconductor material with interesting electronic properties.

Therefore option D) phosphorous is correct.

To know mroe about phosphorus:

https://brainly.com/question/17130833

#SPJ3

The following aqueous solutions represents good buffer systems:

A buffer is a solution used to stabilize the pH (acidity) of a liquid.

A good buffer system is generally known to contain close or equal concentrations of a weak acid and its conjugate base.

Based on the above explanation, the following represents a good buffer system as they are between their weak acid and conjugate base:

Learn more about buffer at: https://brainly.com/question/22821585

#SPJ1

The molar mass of the compound is = 1.42g/ mol

∆Tb = kB × molarity

∆Tb = 102.3°C

Kb = 0.510 °C/m

Molarity= electrolyte mass × water solubility/ Mw× mass of water.

That is,

102.3°C= 0.51× 83.5×1000/Mw × 291.7

Make Mw the subject of formula,

Therefore,

Mw = 0.51 × 83.5×1000/ 102.3 × 291.7

Mw= 42,585/29,840.91

Mw= 1.42g/mol

Learn more about molarity here:

https://brainly.com/question/14469428

#SPJ1

The generic reaction a + b = c, represents a synthesis or combination reaction, which is a kind of chemical reaction.

A synthesis, or combination reaction, is a kind of reaction in which two substances combine to form a bigger molecule.

The generic reaction is:

a + b = c

Some common synthesis reactions are:

Fe + S = FeS

O₂ + 2 SO₂ = 2 SO₃

CaO + CO₂ = CaCO₃

In all the examples above, we can verify that the substances (elements or compounds) combine with each other to form another substance (product).

The generic reaction a + b = c, represents a synthesis or combination reaction, which is a kind of chemical reaction.

Learn more about synthesis reactions here: https://brainly.com/question/16560802

#SPJ1

The wavelength is obtained as 122 nm. Option A

We know that from the Bohr model of the atom, an electron can move from a higher energy level to a lower energy level or from a lower energy level to a higher energy level. This is the idea of energy quantization as put forward by Neill Bohr.

The wavelength can be obtained by the use of the formula;

1/λ = RH(1/n^2initial - 1/n^2 final)

λ = wavelength of the emitted light

RH = Rydberg's constant

n intial = initial energy level

nfinal = final energy level

Thus;

1/λ = 1.09 * 10^7(1/1^2 - 1/2^2)

1/λ = 1.09 * 10^7( 1 - 0.25)

λ = 122 nm

Learn more about the wavelength:https://brainly.com/question/13533093

#SPJ1