Why is the 6 m naoh solution diluted before titrating the vinegar sample? How might your results be affected if you used the 6 m solution rather than the 0. 3 m naoh?

Answer:

43 g N₂

Explanation:

To find the mass of N₂ required, you need to (1) convert grams H₂ to moles H₂ (via molar mass), then (2) convert moles H₂ to moles N₂ (via mole-to-mole ratio from equation coefficients), and then (3) convert moles N₂ to grams N₂ (via molar mass). It is important to arrange the conversions in a way that allows for the cancellation of units. The final answer should have 2 sig figs to match the amount of sig figs of the given value.

Molar Mass (H₂): 2(1.008 g/mol)

Molar Mass (H₂): 2.016 g/mol

Molar Mass (N₂): 2(14.009 g/mol)

Molar Mass (N₂): 28.018 g/mol

1 N₂(g) + 3 H₂(g) -----> 2 NH₃(g)

9.3 g H₂           1 mole             1 mole N₂             28.018 g
--------------  x  ----------------  x  --------------------  x  ------------------  =  43 g N₂
                        2.016 g            3 moles H₂            1 mole

The mass of CH₄ that is consumed is 10.598 g.

The enthalpy of a system is defined as the sum of the internal energy of a system and the energy that is produced due to its pressure and volume.

It is given by

H = U+PV

The following reaction takes place during the combustion of CH₄

[tex]CH_4(g)+2O_2(g)\rightarrow CO_2(g)+2H_2O(g)[/tex]

Energy evolved during the combustion, E = 587.9 kJ

Enthalpy of combustion of methane, ∆H = 890.3 kJ

[tex]No of moles of CH_4 =\frac{energy evolved}{enthalpy of combustion}[/tex]

= 587.9 /890

Mass of CH₄  that is consumed = no of moles × molar mass of CH₄

  = 587.9 /890 × 16

   = 10.598 g

The mass of CH₄  which is consumed is 10.598 g

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The photon which is required to raise the temperature of 2.1 gm of water by 1.7 kk is 2.16 x [tex]10^{20} photons[/tex]

Given the following data:

Mass of water = [tex]2.1 gm[/tex]

Change in temperature = [tex]1.7 Kelvin[/tex]

Wavelength of infrared =  [tex]2.9[/tex] х [tex]10^{-4} cm[/tex]

Specific heat capacity of water = 4.18 J/g°K.

Conversion:

100 cm = 1 m

[tex]2.9 X 10^{-4} cm = 2.9 X 10^{-6}[/tex]

To find the amount of photons required to raise the temperature of 2.1 g of water:

First of all, we would determine the quantity of energy required to raise the temperature of water:

Mathematically, quantity of energy is given by the formula;

[tex]Q = mc[/tex]θ

Where:

Q represents the quantity of energy.

m represents the mass of an object.

c represents the specific heat capacity.

∅ represents the change in temperature.

Substituting the given parameters into the formula, we have;

[tex]Q = 2.1(4.18)(1.7)\\\\Q = 14.92 Joules[/tex]

Mathematically, the Planck-Einstein relation is given by the formula:

[tex]E = hf[/tex]

Where:

h is Planck constant.

f is photon frequency.

To find the photon frequency, we would use this formula:

[tex]Photon frequency = \frac{speed}{wavelength} \\\\Photon frequency = \frac{3(10^{8} )}{2.9(10^{-6} )}\\ \\Photon frequency = \frac{300000000}{0.0000029}\\ \\Photon frequency = 1.04 X 10^{14} Hz[/tex]

Applying Planck-Einstein's relation, we would determine the energy required by each of photon:

[tex]E = 6.626[/tex] х [tex]10^{-34}[/tex] х [tex]1.04[/tex] х [tex]10^{14}[/tex]

[tex]E= 6.89[/tex] х [tex]10^{-20} Joules[/tex]

Now, we can calculate the amount of photons required to raise the temperature of 2.1 g of water by using this expression:

[tex]Number of photons = \frac{Q}{E} \\\\Number of photons = \frac{14.92}{6.89(10^{-20} )}\\ \\Number of photons = 2.16 X 10^{20} photons[/tex]

Disclaimer: Given Question is incomplete, please find the correct question:

Water is exposed to infrared radiation of wavelength 2.9x10-4 cm. Assume that all the radiation is absorbed and converted to heat. How many photons will be required to raise the temperature of 2.1 g of water by 1.7 K? Express your answer using two significant figures.

Thus the concluded that number of photon is 2.16 x [tex]10^{20}[/tex] photons.

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The intermolecular forces are present between the molecules and allow their interactions. The ion-dipole force is present between the water and the chloride ion.

Ion-dipole intermolecular forces are present when the molecules have an ion and a neutral molecule that can interlink through an electrostatic attraction. These forces are present in solutions.

The chloride ions have a negative charge, whereas the water molecule has a neutral charge. Water is a polar molecule that has a partial negative and positive charge that can bond with the anion (chloride ion).

Therefore, the water and the chloride ions have ion-dipole intermolecular forces.

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The activation energy for this reaction is - 55.5 kJ/mol

Calculation,

Given data,

First temperature [tex]T_{1}[/tex] =  302°C = 302+273 = 575 K

Second temperature [tex]T_{2}[/tex] =  508°C =  508+273 = 781 K

rate constant at  302°C = 2. 45 × [tex]10^{-4}[/tex] lit/mol s

rate constant at 508°C =  0. 0965 lit/mol s.

Value of universal gas constant = 8.3145 J/k mol.

Apply Arrhenius equation,

㏒[tex]K_{1} /K_{2}[/tex] = [tex]E_{a}/2.203R[/tex] [1/ 575 K - 1/781 K]

㏒2. 45×[tex]10^{-4}[/tex] lit/mol s/0.0965 lit/mol s = [tex]E_{a}[/tex] /2.303×8.3145 J/k mol[781-575/575K×781 K]

[tex]E_{a}[/tex] = - 55.5 kJ/mol

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91.4 grams

91.4 grams of kcl in grams must be added to 500 ml of a 0. 15 m kcl solution to produce a 0. 40 m solution.

C = mol/volume

2.45M=mol/0.5L

2.45M⋅0.5L = mol

mol = 1.225

Convert no. of moles to grams using the atomic mass of K + Cl

1.225mol * [tex]\frac{39.1+35.5}{mol}[/tex]

mol=1.225

=1.225 mol . [tex]\frac{74.6g}{mol}[/tex]

=1.225 . 74.6

=91.4g

therefore, 91.4 grams of kcl in grams must be added to 500 ml of a 0. 15 m kcl solution to produce a 0. 40 m solution.

What is 1 molar solution?

In order to create a 1 molar (M) solution, 1.0 Gram Molecular Weight of the chemical must be dissolved in 1 liter of water.

58.44 g make up a 1M solution of NaCl.

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Answer:

B.) Trigonal planar

Explanation:

This molecule has 3 bonds and no lone pairs. The angles are all 120° and the bonds are within the same plane. These molecules have the molecular shape of trigonal planar.

The number of electrons, which are present in the nonbonding π molecular orbital of the allyl anion is "0".

Anions, cations, but also allylic radicals have always been frequently mentioned as reaction intermediates. Each one has three adjacent [tex]sp^{2}[/tex]-hybridized carbon centers, and they all rely on resonance for stability. Two resonance structures would be used to present each species, with the charge as well as unpaired electron scattered across both the 1,3 and 0 positions.

The Aufbau principle states that these orbitals would fill up based on the order of stability, therefore a typical pi bond, will have 2 electrons in the Pi orbital as well as zero in the Pi* orbital.

Therefore, the correct answer will be option (d)

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The percentage yield of the  new production technique is 82.8%

Production is the procedure by which finished products are obtained form the raw materials. The production process involves the passing of raw materials through a certain procedure that involves the use of certain machines and equipment to give us the required products.

We are told in the question that there are three shifts;

Shift 1 produces 4562 grams

Shift 2 produces 5783 grams

Shift 3 produces 5247 grams

Average production from the three shifts = 4562 grams + 5783 grams +  5247 grams/3 = 5197 grams

The theoretical average yield is =  7000 grams + 7000 grams + 7000 grams/3 = 7000 grams

Now the percentage yield = actual yield/ theoretical yield * 100/1

percentage yield = 5197 grams/7000 grams * 100/1

percentage yield = 82.8%

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Al₂(SO₄)₃ + 3BaI₂ → 2AlI₃ + 3BaSO₄

The number of π molecular orbitals in a molecule is always equal to the number of p orbitals used to construct the π bonds.

An electron's position and wave-like behavior within a molecule are described by a mathematical function called a molecular orbital. Chemical, as well as physical properties like the probability of locating an electron in a particular area, can be determined using this function.

A molecular orbital would be created when two atomic orbitals cross one other along the internuclear axis. A molecular orbital is created when two atomic orbitals cross each other sideways.

Therefore, the number of π molecular orbitals in a molecule is always equal to the number of p orbitals used to construct the π bonds.

Hence, the correct answer will be option (a).

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The correct option is (c) 101.55.

What is copper fluoride used for?

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Answer:

-----> 2 CH₄ + 2 NH₃ + 3 O₂ -----> 2 HCN + 6 H₂O

-----> CH₄ = Whichever reactant produces the smaller amount of product is the limiting reagent. This is because the limiting reagent runs out before all of the other reactant is completely used. Because CH₄ produces the smaller amount of product, it is the limiting reagent.

-----> 13.5 grams HCN

Explanation:

Part 1:

An equation is balanced when there is an equal amount of each reactant on both sides of the reaction. These amounts can be modified by adding coefficients in front of the molecules.

The unbalanced equation:

CH₄ + NH₃ + O₂ -----> HCN + H₂O

Reactants: 1 carbon, 7 hydrogen, 1 nitrogen, 2 oxygen

Products: 1 carbon, 3 hydrogen, 1 nitrogen, 1 oxygen

The balanced equation:

2 CH₄ + 2 NH₃ + 3 O₂ -----> 2 HCN + 6 H₂O

Reactants: 2 carbon, 14 hydrogen, 2 nitrogen, 6 oxygen

Products: 2 carbon, 14 hydrogen, 2 nitrogen, 6 oxygen

Part 2:

You can determine the limiting reactant by converting each reactant mass (besides O₂) to a product mass. Whichever reactant produces the smaller amount of product is the limiting reagent. This is because the limiting reagent runs out before all of the other reactant is completely used.

Let's convert to HCN because Part 3 also wants to know how much HCN is produced. To find this amount, you need to (1) convert grams reactant to moles reactant (via their molar masses), then (2) convert moles reactant to moles HCN (via the mole-to-mole ratio from equation coefficients), and then (3) convert moles HCN to grams HCN (via its molar mass).

Molar Mass (CH₄): 12.011 g/mol + 4(1.008 g/mol)

Molar Mass (CH₄): 16.043 g/mol

Molar Mass (NH₃): 14.009 g/mol + 3(1.008 g/mol)

Molar Mass (NH₃): 17.033 g/mol

Molar Mass (HCN): 1.008 g/mol + 12.011 g/mol + 14.009 g/mol

Molar Mass (HCN): 27.028 g/mol

8 g CH₄           1 mole            2 moles HCN         27.028 g
--------------  x  ----------------  x  ----------------------  x  ----------------  =  13.5 g HCN
                       16.034 g          2 moles CH₄            1 mole

10 g NH₃           1 mole            2 moles HCN          27.028 g
---------------  x  ----------------  x  -----------------------  x  ----------------  =  15.9 g HCN
                         17.033 g          2 moles NH₃            1 mole

Because CH₄ produces the smaller amount of product, it is the limiting reagent. Therefore, the actual amount of HCN produced is 13.5 g.

Electrical resistivity is the measure of the material that can resist the electrical charge. The resistance of the copper wire at 80°C will be 146.43 Ω. Thus, option E is correct.

Electrical resistance is defined as the opposing force that counteracts the electrical charge flow in the material. It is expressed in the terms of the ohms (Ω).

Resistance is calculated as,

R₈₀ = R₀(1 + αΔT)

Given,

Temperature coefficient of resistance (α) = 0.0068 °C⁻¹

ΔT = 60°C

Resistance of a wire (R₀) at 20° C = 104 Ω

Resistance of a wire (R₈₀) at 80°C =?

Substituting values above:

R₈₀ = (104 )[1 + (0.0068)(60)]

R₈₀ = 146.43 Ω

Therefore, option E. 146.43 Ω is the resistance of the copper wire at 80°C.

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Your question is incomplete, but most probably your full question was, The temperature coefficient of resistivity for copper is 0.0068 °C⁻¹. If a copper wire has a resistance of 104 Ω at 20°C, what is its resistance at 80°C?

Because carbon dioxide dissolves in water and is transported by rain to the surface where it combines with rocks to generate carbonates, the Earth's atmosphere contains significantly less carbon dioxide than Venus's atmosphere.

Since Venus' atmosphere is around 100 times thicker than the earth's and extremely dense. Venus must be sufficiently close to the Sun for the little carbon dioxide in its early atmosphere to have heated the surface and released additional carbon dioxide into the atmosphere. Nitrogen makes up 79% of the atmosphere on Earth, along with oxygen (20%) and a trace amount of other gases including carbon dioxide and water vapor. On Venus and Mars, however, carbon dioxide makes up the majority of the atmosphere.

In Venus's original ocean drained, water vapor molecules were dispersed by ultraviolet light, and hydrogen was released into space. There was no longer any surface water, and the amount of carbon dioxide increased.

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The hybridization states of the carbon atoms involved in the conversion of trans to cis retinal is sp2.

What is Hybridization?

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Sucrose, a disaccharide (consisting of two monosaccharides), is table sugar.

A digestive enzyme called sucrase catalyses the breakdown of sucrose into its component sugars, fructose and glucose. One type, sucrase-isomaltase, is secreted at the brush boundary of the small intestine. Invertase, a form of the sucrase enzyme that is more frequently found in plants, also hydrolyzes sucrose but does it in a different way.

Maltose is converted to glucose by maltase. Succrase and lactase, respectively, break down other disaccharides like sucrose and lactose. Sucrase and lactase are enzymes that break down sucrose (also known as "table sugar") and lactose (sometimes known as "milk sugar"), respectively, into glucose and fructose.

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Nh4cl is sometimes preferred instead of hcl or h2so4 for "acid" work-up after grignard reactions, particularly when the expected and desired product is a tertiary alcohol because NH4+ is a much milder acid than HCl or H2SO4, which achieve the protonation of

the oxyanion to yield the alcohol while minimizing the risk of dehydration.

Ammonium chloride (NH4Cl) is the used as reagent that quenches the magnesium alkoxide product of the Grignard addition.

It is a proton source without being acidic as in acidic medium the protonation of the tertiary alcohol product and elimination to the alkene.

In the presence of HCl or any other strong acid protonation proceed and form alkene but not with ammonium chloride.

Thus from above we concluded that Nh4cl is preferred instead of hcl or h2so4 for "acid" work-up after grignard reactions.

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The pH at the equivalence point for the titration of 0. 22 m HCN with 0. 22 m NaOH is 11.17

Calculation,

Concentration of NaCN = 0. 22 m/ 2 = 0.11 M ( at equal volumes of acid and base will be used).

The equilibrium is ,

HCN +[tex]H_{2} O[/tex]  → [tex]H^{+} + CN^{-}[/tex]

C(1-x)              Cx      Cx

Where x , is the degree of hydrolysis and

[tex]K_{h}[/tex] = C[tex]x^{2}[/tex]/(1-x)

We know that [tex]K_{h}[/tex] = [tex]K_{w}/K_{a}[/tex] = 1 ×[tex]10^{-14}[/tex]/4. 9 ×[tex]10^{-10}[/tex] =  2.04×[tex]10^{-5}[/tex]

[tex]K_{h}[/tex] =  C[tex]x^{2}[/tex] =   2.04×[tex]10^{-5}[/tex]  = 0.11 M×[tex]x^{2}[/tex]

[tex]x^{2}[/tex] =  2.04×[tex]10^{-5}[/tex]/0.11 M

x = 1.36×[tex]10^{-2}[/tex]

[tex][OH^{-} ][/tex] = Cx =  1.36×[tex]10^{-2}[/tex] × 0.11 M = 0.15×[tex]10^{-2}[/tex]

[tex][H^{+} ][/tex] =  1 ×[tex]10^{-14}[/tex]/ 0.15×[tex]10^{-2}[/tex] = 6.66×[tex]10^{-12}[/tex]

pH = -㏒[tex][H^{+} ][/tex] = -㏒6.66×[tex]10^{-12}[/tex] = 11.17

The pH at the equivalence point for the titration is  11.17.

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Answer:

you better give me brainliest

Explanation:

Zinc nitrate and calcium nitrate solution can be distinguished by reaction with ammonium hydroxide. Zinc forms a white gelatinous ppt. whereas there is no precipitation of calcium hydroxide even with excess of ammonium hydroxide

The major product is p-bromo N,N,N -trimethylaniliniumiodide when p-bromoaniline react with excess CH₃I.

When p-bromoaniline react with methyl iodide it produces p-bromo N,N-dimethylaniline.

When  p-bromo N,N-dimethylaniline reacts with excess methyl iodide leading to the production of p-bromo N,N,N -trimethylaniliniumiodide.

Thus from the above conclusion we can say that The major product is p-bromo N,N,N -trimethylaniliniumiodide.  when p-bromoaniline react with excess CH₃I.

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The combination of properties would be expected to lead to the most viscous liquid include:

This is defined as the resistance of a liquid to flow and is characterized by its sticky nature.

This is as a result of the strong intermolecular forces which holds the atoms together and low temperature keeps them in shape thereby making it the most appropriate c hoice.

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NaBH4 is blind + will reduce other functional groups.

Functional groups:

The aldehyde group in o-vanillin would be converted to alcohol if it had been added during step one (imine production). Because the carbon is not sufficiently nucleophilic, p-toluidine would not attack and imine would not form in the maximum yield.

Regardless of the other atoms in the molecule, a functional group is a collection of atoms that have specific chemical characteristics. Covalent bonds bind the atoms in a functional group to the other molecules in the molecule as well as to one another. Examples: Alcohol, Aldehyde, Ketone, Carboxylic acid, Halogens, Double & Triple covalent bonds.

A carbonyl in which the carbon atom is linked to at least one hydrogen atom is called an aldehyde. An R-group or a hydrogen atom could be the other group joined to the carbonyl. Aldehydes are a highly reactive form of carbonyl because of the tiny size of the hydrogen atom, which makes it relatively simple for other molecules to approach the partial positive charge on the carbonyl carbon. Aldehydes are adaptable reactants used in numerous different organic synthesis processes. Numerous aldehydes also have unique tastes and odors.

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The actual  theoretically yield from this reaction is 86.5 grams.

What is theoretically yield?

∵ The percentage yield = (actual yield/theoretical yield) * 100.

To calculate the theoretical yield from the balanced reaction:

             CaCO₃ + 2HCl → CaCl₂ + CO₂ + H₂O,

It is clear that 1 mole of CaCO₃ reacts with 2 mole of HCl to produce 1 mole of CaCl₂, 1 mole of CO₂, and 1 mole H₂O.

to calculate the no. of moles of 95.0 g CaCO₃

n = mass/molar mass = (95.0 g)/(100.0869 g/mole) = 0.95 mol.

Using cross multiplication:

1 mole of CaCO₃ produce  → 1 mole of CaCl₂, from stichiometry.

∴ 0.95 mole of CaCO₃ produce → 0.95 mole of CaCl₂.

∴ The mass of CaCl₂ (theoretical yield) = (no. of moles) * (molar mass)                         ⇒(0.95 mole)*(110.98  g/mole) = 105.34 g.

∵ The percentage yield = (actual yield/theoretical yield)*100.

The percentage yield = 82.15%, theoretical yield = 105.34 g.

∴ The actual yield of CaCl₂ = (The percentage yield)(theoretical yield)/100

                                 = (82.15%)(105.34 g)/100 = 86.53 g ≅ 86.5 g.

So, the actual  theoretically yield from this reaction is 86.5 grams.

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The kf of Ag(NH₃)₂ for the given equation is 2.786 x 10⁷.

kf value can be calculated by dividing the molal concentration with the freezing point of depression.

The reaction are given:

Ag+(aq) + e- ⇋ Ag(s) E0= 0.81 V

Ag(NH₃)₂ +(aq) + e- ⇋ Ag(s) + 2NH₃(aq) E0= 0.37 V

To get Kf of Ag(NH₃)₂  we will rearrange the above written equations

a. Ag +(aq) + e- ⇋ Ag(s) E0= 0.81 V

b. Ag(s) + 2NH₃(aq) ⇋ Ag(NH₃)₂ +(aq) + e- E0= - 0.37 V

Adding equation (a) and equation (b) we will get

Ag +(aq) + 2NH₃(aq) ⇋ Ag(NH₃)₂  + (aq) Eo = 0.81 -0.37 = 0.44 V

By the Ernst equation,

E = E° - 0.0591 logkf

Now Kf is calculated at equilibrium and at equilibrium E = 0,

The number of transfer of electron is 1 ( 1 e-) , n=1

E° = 0.44 V

Substituting all the values in Ernst equation

0 - 0.44 - 0.0591/ 1 logkf

logkf = 0.44/ 0.0591

kf = 10 (0.44/ 0.0591)

Kf = 2.786 x 10⁷

Hence, Kf of Ag(NH₃)₂ for the given equation is 2.786 x 10⁷.

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Balanced chemical equation for reaction of hydronium ions with calcium carbonate will be as follows:

2H3O+ (aq) + CaCO3 (s) => Ca2+ (s) + 3H2O (l) + CO2 (g)

In this balanced chemical equation, acidic aqueous solution of hydronium ion (H3O+) reacts with calcium carbonate salt (CaCO3) resulting in the formation of calcium cation (Ca2+) an alkali, that results in neutralization of excessive acid. It also forms liquid water (H2O) along with liberation of carbon dioxide gas (CO2).  All acids stronger than hydrogen carbonate, provide their calcium salts dissolved in water yielding carbon dioxide, because a bare hydrogen ion has no chance of surviving in water.

To balance this chemical equation, 2 molecules of hydronium ions react with 1 molecule of calcium carbonate resulting  in formation of 1 molecule of calcium cation, 3 molecules of water and 1 molecule of carbon dioxide. The reaction proceeds at room temperature.

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The hydroxide ion concentration [OH-] in an aqueous solution is 6.66 x 10⁻⁹ M

Experimental measurements of the pKw of water at 25ºC yielded a result of 14.0. The same method used to determine the pKa of all other water-soluble compounds that can function as acids in aqueous solution can also be used to determine this value from the examination of thermodynamic or electrochemical data for these aqueous solutions.

Water has a pkw=14

So it can be represented as,

[H+] [OH-] = 1×10^-14

Given [H+] = 1. 5×10^−6

So, [OH-] = (1*10^-14) / ( 1.5*10^-6)

               = 6.66 x 10⁻⁹ M

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Haloalkanes are another name for alkyl halides. Alkyl halides are substances in which halogen atoms have taken the place of one or more hydrogen atoms in an alkane (fluorine, chlorine, bromine, or iodine).

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