p-Nitrobenzaldehyde is more reactive toward nucleophilic additions than pmethoxybenzaldehyde. Explain

Answers

Answer 1

The presence of electron donating methoxy group in  p-methoxybenzaldehyde , makes it less reactive towards  nucleophilic additions.

Nucleophilic addition reactions that involve of p-Nitrobenzaldehyde and p-methoxybenzaldehyde both occur at the C=O functional group. The electron density around the carbonyl is a key factor that controls the reactivity of each compound.

In  p-Nitrobenzaldehyde, the electron withdrawing nitro group decreases the electron density around the carbonyl making it more vulnerable to nucleophilic attack.

In p-methoxybenzaldehyde, the methoxy group donates electrons by resonance towards the carbonyl thereby increasing the electron density around it so that it is less reactive towards nucleophillic addition reaction.

The nucleophilic attack on p-Nitrobenzaldehyde leads to more resonance structures than nucleophilic attack on p-methoxybenzaldehyde.

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Related Questions

1: Given that Ka for HCOOH is 1.8×10^-4 at 25°C what is the value of b for COOH− at 25 °C?
Kb=
2: Given that b for (CH3)2 NH is 5.4×10^-4 at 25°C, what is the value of Ka for (CH3)2NH+2 at 25 °C?
Ka=

Answers

Explanation:

At 25 °C Dissociation constant of water or Kw = 1× 10^-14 mol2dm-6

Ka × Kb = Kw for all diluted solutions

Ka×Kb = 1 × 10^-14 mol2dm-6

Therefore for question 1 -

COOH- is the conjugate base for HCOOH ( we find the conjugate base by removing an H atom and the Conjugate acid by adding an H atom)

COOH- (aq) + H2O ( l) <-----> HCOOH( aq) + OH-(aq)

So we can apply the above mentioned equation to find Kb value for COOH-

Kb = 5.56 × 10^-11 moldm-3

For question 2-

We can see that (CH3)2NH+2 is the conjugate acid of (CH3)2 NH. (A H atom has been removed so the one with a H atom less is the conjugate base.)

(CH3)2NH+2 (aq) + H2O (l) <-----> (CH3)2 NH (aq) + H3O+ (aq)

So applying the previously mentioned equation we get Ka = 1.85 × 10^-11 moldm-3

Given the ionic formula below, what is the charge on ion X? Be sure to
include the sign (+ or -). Li2 x

Answers

Answer:Charge on X  = (+ 2)

Explanation:

Charge on one Cl = -1

So Charge on two Cl = -2

The molecule = Neutral = 0 charge

So, to make total charge = 0 , the X should have +2 charge

XCl2 = +2 -2 = 0

X = +2

Alkaline earth metals(Be , Mg , Ca , Sr) form such type of compounds

Explanation:

Mechanical waves travel fastest through
A -Solid
B -Liquid
C -Gas
D -Vacuum

Answers

Answer:

A-Solid

Explanation:

Waves travel faster in solids & slowest in gases

Describing Chemical Reactions
Project: Modeling the Conservation of Mass

Answers

Answer:

Step 1: Prepare for the project.

a) Read the entire Student Guide before you begin this project.

b) If anything is unclear, be sure to ask your teacher for assistance before you begin.

c) Gather the materials you will need to complete this project.

Step 2: Review the chemical reaction.

a) The chemical reaction that you will model is shown below. Calcium oxide (CaO) is a white

solid with a crystalline structure. It is made by heating limestone, coral, sea shells, or chalk,

which are composed mainly of calcium carbonate (CaCO3). During the heating process,

carbon dioxide (CO2) is released and calcium oxide (CaO) is produced. Commercially,

calcium oxide is called lime. One of the oldest uses of lime is to make mortar, a substance

used in construction to secure bricks, stones, and blocks together.

CaCO3  CaO + CO2

Step 3: Build a model of the reactant.

a) Use gumdrops and toothpicks to build a model of CaCO3.

b) Select one color of gumdrop for calcium, a second color for carbon, and a third color for

oxygen. Be sure to include a key of your chosen color scheme with your model.

c) Use the periodic table to help you determine the number of bonds each atom will form.

Step 4: Build models of the products.

a) Use gumdrops and toothpicks to build a model of CaO and a model of CO2.

b) Be sure to use the same colors of gumdrops for calcium, carbon, and oxygen as you did in

Step 3. Include a key of your chosen color scheme with your models.

c) Use the periodic table to help you determine the number of bonds each atom will form.

Step 5: Type one to two paragraphs that describe your models and explain the conservation of

mass in the chemical reaction.

a) Create a new blank document. Type your name at the top.

b) Type one to two paragraphs that describe your models and relate them to the law of

conservation of mass. Your document should:

i. identify the names of the reactants and products in the reaction.

ii. identify the number of molecules that make up the reactants and products.

iii. identify the type and number of atoms in each molecule of the reactants and products.

iv. explain what happens during the chemical reaction.

v. explain how mass is conserved during the chemical reaction.

Step 6: Evaluate your project using this checklist.

If you can check each criterion below, you are ready to submit your project.

 Did you create an accurate model of calcium carbonate (CaCO3)? Your model should include

the correct number of gumdrops for each element in calcium carbonate, consistent use of

colors for elements in calcium carbonate, and the correct number and placement of toothpicks

(bonds).

 Did you create an accurate model of calcium oxide (CaO)? Your model should include the

correct number of gumdrops for each element in calcium oxide, consistent use of colors for

elements in calcium oxide, and the correct number and placement of toothpicks (bonds).

 Did you create an accurate model of carbon dioxide (CO2)? Your model should include the

correct number of gumdrops for each element in carbon dioxide, consistent use of colors for

elements in carbon dioxide, and the correct number and placement of toothpicks (bonds).

Did you type one to two paragraphs that describe your models and relate them to the law of

conservation of mass? Your document should include the names of the reactants and

products in the reaction, the number of molecules that make up the reactants and products,

and the type and number of atoms in each molecule of the reactants and products. It should

also explain what happens during the chemical reaction and how mass is conserved during  the reaction

Step 7: Revise and submit your project.

a) If you were unable to check off all of the requirements on the checklist, go back and make  

b) When you have completed your project, submit your models to your teacher for grading.  

c) Submit your document through the virtual classroom. Be sure that your name is on it.

Step 8: Clean up your workspace.

a) Clean up your workspace. Return any extra materials to your teacher and throw away any  trash.

Explanation:

To what volume would you have to change 6.5 Liters of a gas at 1.25 atm in order to
decrease its pressure to 1.0 atm?

Answers

Answer:

8.13 mL

Explanation:

The required volume can be found by using the formula for Boyle's law

[tex]V_2 = \frac{P_1V_1}{P_2} \\[/tex]

where

P1 is the initial pressure

P2 is the final pressure

V1 is the initial volume

V2 is the final volume

From the question we have

[tex]V_2 = \frac{6.5 \times 1.25}{1} = 6.5 \times 1.25 \\ = 8.125[/tex]

We have the final answer as

8.13 mL

Hope this helps you

which two types of food are homogeneous mixtures
A. mustard
B. mayonnaise
C. tossed salad
D. trail mix

Answers


Answer: It’s most likely Mayonnaise and mustard.
Explanation: It’s definitely mayonnaise because it’s not possible to see the different substances and for mustard it depends on what type. Hope this helps. Good luck :)

Problem 07.020 - Heat transferred from cold to hot reservoir Assume that heat in the amount of 100 kJ is transferred from a cold reservoir at 600 K to a hot reservoir at 1050 K contrary to the Clausius statement of the second law. What is the total entropy change

Answers

This problem is describing a system in which 100 kJ of energy is transferred from a cold reservior at 600 K to a hot one at 1050 K. This situation is opposed to the Clausius statement of the second law of thermodynamics, because it is widely known that heat is transferred from hot to cold systems.

However, we can calculate the total entropy change by using the following formula:

[tex]\Delta S =\Delta S _{Low}+\Delta S _{High}[/tex]

Which is broken down as follows:

[tex]\Delta S =\frac{-Q}{T_{Low}} + \frac{Q}{T_{High}}\\\\\\\Delta S =Q(\frac{-1}{T_{Low}} + \frac{1}{T_{High}})[/tex]

Since the heat is assumed to be equal for the both of them. Then, we plug in the given heat and temperatures to obtain:

[tex]\Delta S =100kJ(\frac{-1}{600K} + \frac{1}{1050K})\\\\\Delta S =-0.0714\frac{kJ}{K}[/tex]

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Bethany observes a white crystal that is cube shaped under a microscope.



Based on this observation, Bethany thinks the crystal could be sodium chloride, or table
salt. Because the crystal has an extended structure, she knows that sodium chloride is
not a molecule. Bethany uses gray and white spheres, representing the atoms in
sodium chloride, to make a model of the crystal’s most likely structure, as shown.

a. Provide two reasons why the model accurately represents sodium chloride. Support
your reasons with evidence from the model.

b. Predict whether the melting point should be high or low based on the model.

Answers

Answer:

In nature there are many different minerals we call "Salts". If you look very closely at the particles of table salt, you will find little cubic crystals. These salt crystals are made of sodium chloride (NaCl), and their cubic shape is due to a very specific arrangement of the atoms. As discussed earlier, all of the minerals classified as salts are held together through ionic bonds. The arrangement of atoms, the shapes of the crystals they form, and their mechanical, thermal, and electrical properties are all due to this special type of bonding

The two reasons why the model shows sodium chloride is that:

Sodium chloride crystals are cubic in their form as they have crystalline structure.

Why sodium chloride does not exist as molecule?

The other is that:

Sodium chloride does exist as an aggregates of a bigger number of ions that are oppositely charged as shown using  gray and white spheres.The melting point will be high  based on the model as because Sodium chloride is known to have high melting and boiling point.

Note that a lot of Formula unit cannot exist as a single entity. Because of this, compound such as NaCl exist only as an aggregates of a more bigger number of ions that are oppositely charged .

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If such an ion is negatively charged and includes one or more oxygen atoms

Answers

Answer:

atom

Explanation:

The sodium atom has a single valence electron that it can easily lose. (If the sodium atom loses its valence electron, it achieves the stable electron configuration of neon.) The chlorine atom has seven valence electrons and can easily gain one electron.

A 14.0 L container at 323 K holds a mixture of two gases with a total pressure of 8.00 atm. If there are 1.50 mol of Gas A in the mixture, how many moles of Gas B are present

Answers

The number of moles of gas B present in the gas mixture is 2.72 moles.

The given parameters;

Volume of the gases, V = 14 LTemperature of the gases, T = 323 KTotal pressure of the gases, P = 8 atmNumber of moles of gas A = 1.5 moles

The total number of moles of the gases is calculated by applying ideal gas law;

PV = nRT

where;

R is ideal gas constant = 0.0821 L.atm./mol.K

n is the total mole of the gases

[tex]n =\frac{PV}{RT} \\\\n = \frac{8 \times 14}{0.0821 \times 323} \\\\n = 4.22 \ moles[/tex]

The number of moles of gas B is calculated as follows;

[tex]n_B = 4.22 - n_A\\\\n_B = 4.22 - 1.5\\\\n_B = 2.72 \ moles[/tex]

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explain in details what a matter is...!!!​

Answers

Answer:

umm

Explanation:

matter makes up everything. everything is matter

the more matter an object has the more mass It has

what does cost-effective mean? im kind of confused on cost-effective and time-effective things and i keep getting mixed up :(

Answers

Cost-effective definition: producing good results without costing a lot of money. E.g: that machine is very cost effective, it made 200 shirts with only a dollar.

Time effective definition: how well time was used. E.g that machine is very time-effective, it made 200 pants in one hour!

Would appreciate brainly <3

Can anybody complete this for me?

Answers

Answer:

I wish i could

Explanation:

Calculate the moles of HCl in 15 mL of a 0.50 M solution.

Answers

Explanation:

[tex]\tiny\implies Molarity = \dfrac{no. \: of \: moles \: of \: solute \times 1000}{volume \: of \: the \: solution \: (in \: ml)} [/tex]

[tex]\tiny\implies 0.50 = \dfrac{no. \: of \: moles \: of \: solute \times 1000}{15}[/tex]

[tex]\tiny\implies no. \: of \: moles \: of \: solute \times 1000 = 0.50 \times 15[/tex]

[tex]\tiny\implies no. \: of \: moles \: of \: solute \times 1000 = 7.5[/tex]

[tex]\tiny\implies no. \: of \: moles \: of \: solute = \dfrac{7.5}{1000} [/tex]

[tex]\tiny\implies \bf no. \: of \: moles \: of \: solute = 0.075 \: mol[/tex]

2. What pressure is required to compress 196.0 L of air at 1.00 atmosphere into a cylinder
whose volume is 26 0 L? (2 points)

Answers

Answer:

7.54 atm

Explanation:

The required pressure can be found by using the formula for Boyle's law which is

[tex]P_2 = \frac{P_1V_1}{V_2} \\[/tex]

where

P1 is the initial pressure

P2 is the final pressure

V1 is the initial volume

V2 is the final volume

From the question we have

[tex]P_2 = \frac{1 \times 196}{26} = \frac{196}{26} \\ = 7.538461...[/tex]

We have the final answer as

7.54 atm

Hope this helps you

Which of the following is NOT a type of evidence indicating that a chemical change has occurred? *

- fizzing/bubbling
- heat is released
- solubility
- sound is given off

Answers

Answer:

sound is given off

Explanation:

due to a number of scientific research sound that is given off of an object is not due to a chemical reaction.

Find five household items that contain ionic compounds. List the following information for each compound: a.name of the product
b. the chemical name of the ionic compound
d.the chemical formula of the ionic compound c. identify the ions present in each compound

Answers

Answer:

D . GOD BLESS .

Explanation:

A hydrochloric acid solution is standardized by titrating 0.2329 g of primary standard sodium carbonate to a methyl red end point by boiling the carbonate solution near the end point to remove carbon dioxide. If 42.87 mL acid is required for the titration, what is its molarity
HELP

Answers

The molarity of the acid, HCl solution is 0.103 M

We'll begin by calculating the number of mole in 0.2329 g of Na₂CO₃

Mass of Na₂CO₃ = 0.2329 g

Molar mass of Na₂CO₃ = (23×2) + 12 + (16×3) = 106 g/mol

Mole of Na₂CO₃ =?

Mole = mass / molar mass

Mole of Na₂CO₃ = 0.2329 / 106

Mole of Na₂CO₃ = 0.0022 mole

Next, we shall determine the number of mole of HCl needed to react with 0.0022 mole of Na₂CO₃

Na₂CO₃ + 2HCl —> 2NaCl + H₂O + CO₂

From the balanced equation above,

1 mole of Na₂CO₃ reacted with 2 moles of HCl.

Therefore,

0.0022 mole of Na₂CO₃ will react with = 0.0022 × 2 = 0.0044 mole of HCl

Finally, we shall determine the molarity of the HCl.

Mole of HCl = 0.0044 mole

Volume = 42.87 mL = 42.87 / 1000 = 0.04287 L

Molarity of HCl =?

Molarity = mole / Volume

Molarity of HCl = 0.0044 / 0.04287

Molarity of HCl = 0.103 M

Thus, the molarity of the acid, HCl solution is 0.103 M

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an alloy composed of tin, lead, and cadmium is analyzed. the mole ratio of sn:pb is 2.73:1.00, and the mass ratio of pb:cd is 1.78:1.00. what is the mass percent composition of pb in the alloy

Answers

This problem is describe the mole-ratio composition of an allow composed by tin, lead and cadmium. Ratios are given as Sn:Pb 2.73:1.00 and Pb:Cd is 1.78:1.00, and we are asked to calculate the mass percent compositon of Pb in the allow.

In this case, according to the given information, it turns out possible realize that the following number of moles are present in the alloy, according to the aforementioned ratios:

[tex]2.73mol Sn\\\\1.00molPb\\\\\frac{1.00molPb*1.00molCd}{1.78molPb}= 0.562molCd[/tex]

Next, we calculate the masses by using each metal's atomic mass:

[tex]m_{Sn}=2.73mol*\frac{118.7g}{1mol}=324.05g\\\\ m_{Pb}=1.00mol*\frac{207.2g}{1mol}=207.2g\\\\m_{Cd}=0.562mol*\frac{112.4g}{1mol}=63.2g[/tex]

Thus, the mass percent composition of each metal is shown below:

[tex]\%Sn=\frac{324.05g}{324.05g+207.2g+63.2g} *100\%=54.5\%\\\\\%Pb=\frac{207.2g}{324.05g+207.2g+63.2g} *100\%=34.9\%\\\\\%Cd=\frac{63.2}{324.05g+207.2g+63.2g} *100\%=10.6\%[/tex]

So that of lead is 34.9 %.

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Learn more:

Where did the atoms come from in the first place?

Answers

Answer:

All the carbon atoms in the human body were created in the stars. Elementary particles, such as protons, were formed during the "big bang"; that amazing moment about 14 billion years ago in which the universe got it's start.

pls help me right now​

Answers

Answer:

LETTER

1. D. PURE SUBSTANCES CAN BE FURTHER BROKEN DOWN INTO SIMPLER SUBSTANCES.

2.A

PO PLEASE MARK A BRAINLIESTS ANG MARK A 5 STAR ANG HEART PO PLEASW

5. Select the answer for both questions ​

Answers

Answer:

engey

Explanation:

the process of breaking food is to release energy is called _____​

Answers

Answer:

The process by which food is broken down to release energy is called respiration

I hope it helps.

Answer:

Respiration

Explanation:

hope this helps.

Hot air balloons are open at their lower and end. A basket is suspended from the balloon and can take several passengers as well as the pilot. A propane burner fixed to the basket is used to heat up the air in the balloon A hot balloon has a volume of 1500 m3 and its volume does not change when the enclosed air is heated.

1) Use the ideal gas equation, pV=nRT. to calculate how many molecules of the balloon contains at a temperature of 10 °C and a pressure 10.1 KP.
2) Calculate the mass of air it contains, assuming an average M of 29.​

Answers

(a) The number of molecules contained by the balloon at the given condition is 6,438.97 moles.

(b) The mass of air in the balloon is 186.73 kg.

The given parameters;

volume of the balloon, V = 1500 m³temperature, T = 10⁰C = 273 + 10 = 283 Kpressure, = P = 10.1 kPa = 10,100 Pa

The number of molecules contained by the balloon at the given condition is calculated as follows;

[tex]PV = nRT[/tex]

where;

R is ideal gas constant = 8.314 J/mol.Kn is the number of moles air in the balloon;

[tex]n = \frac{PV}{RT} \\\\n = \frac{10,100 \times 1500}{8.314 \times 283} \\\\n = 6,438.97 \ moles[/tex]

The mass of air in the balloon is calculated as;

[tex]n = \frac{m}{M} \\\\m = nM\\\\m = 6,438.97\ moles \ \times \ 29 \ g/mol\\\\m = 186.73 \ kg[/tex]

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After being placed on the table where should the ocular lenses face?

Answers

Body surface area is calculated a) in m2 from weight and height. b) from height. c) from weight. d) in meters from weight and height.

In this photograph, a soccer player is about to kick the ball. Use the situation to explain that when two objects interact, the force between them can cause energy to be transferred. In your response, identify the type of energy that each object has before they interact, the forces exerted when the objects interact, and the type of energy that each object has after they interact.

Answers

The explanation to the question is stated as follows:

Newton's first law of motion states that: a body will continue in its state of rest or uniform motion unless an external force acts on it. So then, the ball initially possesses potential energy because it was at rest. While the leg of the soccer player possesses kinetic energy because its in motion.

Thus, when the player hits the ball, a force known as push has been applied. This would ensure that the ball compels and moves in the direction of the applied force. Therefore after the interaction, the leg of the player now possesses potential energy, since it would come to rest after hitting the ball. While the ball would start moving, now possessing kinetic energy.

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Convert the heat of neutralization of acetic acid from -49,8 kj/mmol to calories per
millimole and ROUND TO ONE DECIMAL PLACE (1 cal = 4.184 J)
DO NOT INCLUDE UNITS

Answers

This question is providing the exothermic heat of neutralization of acetic acid in units of kilojoules per mollimole (-49,8 kj/mmol) and asks for the same value but in calories per millimole which results -11,902.5 cal/mmol.

In this case, according to the given problem, it turns out necessary to solve a two-factor conversion in order to convert the kilojoules to joules and finally to calories as shown below:

[tex]-49.8\frac{kJ}{mmol}*\frac{1000J}{1kJ}*\frac{1cal}{4.184J}[/tex]

Thus, we cancel out the kJ and J, to obtain the following result, rounded to one decimal place:

[tex]-11,902.5\frac{cal}{mmol}[/tex]

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Dont need work pls help

Answers

The answer is a low is the correct answer

as the solar nebula cooled which compounds were the first to condense from a gas to a solid? Rock water ice or metal

Answers

As the solar nebula cooled METAL compounds are the first to condense from a gas to a solid. The solar nebula gave birth to the Solar system.

A solar nebula is a disc-shaped cloud of gases and grain dust, which gave birth to the Sun and planets of the Solar system, approximately 4.6 billion years ago.

The solar nebula is at the beginning a mixture of interstellar gases (hydrogen and helium) and dust grains.

As the solar nebula cools, heavy elements such as metals in the disk condensate into planetesimals.

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What instruments are used to measure moleculars vibration , rotation and translation?

Answers

Answer:

you hear

Explanation:

beautiful hear can be wonderful day in your life so to be rotations is not a big deal

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