An analytical chemist weighs out 0.281g of an unknown diprotic acid into a 250mL volumetric flask and dilutes to the mark with distilled water. He then titrates this solution with 0.0700M NaOH solution. When the titration reaches the equivalence point, the chemist finds he has added 48.3mL of NaOH solution. Calculate the molar mass of the unknown acid.

Answers

Answer 1

Answer:

166 g/mol

Explanation:

Step 1: Write the neutralization reaction

H₂A + 2 NaOH ⇒ Na₂A + 2 H₂O

Step 2: Calculate the reacting moles of NaOH

48.3 mL of 0.0700 M NaOH react.

0.0483 L × 0.0700 mol/L = 3.38 × 10⁻³ mol

Step 3: Calculate the reacting moles of H₂A

The molar ratio of H₂A to NaOH is 1:2. The reacting moles of H₂A are 1/2 × 3.38 × 10⁻³ mol = 1.69 × 10⁻³ mol.

Step 4: Calculate the molar mass of H₂A

1.69 × 10⁻³ moles of H₂A have a mass of 0.281 g. The molar mass of H₂A is:

M = 0.281 g / 1.69 × 10⁻³ mol = 166 g/mol


Related Questions

The map below shows the range of three types of grasslands in the United
States. What do tallgrass prairies have that shortgrass prairies lack?
23
Blue: Shortgrass prairie
Purple: Mixed grass prairie
Green: Tallgrass prairie
A. Infertile soil
B. Cedar breaks
C. More rainfall
D. Rain shadows

Answers

Answer:

More rainfall is the correct answer.

Explanation:

a-pe/x

ana walked though this part of the forest when she passed under some low branches water drops fell on her head what most likely caused the water drops to form

Answers

Answer:

well gravity

Explanation:

gravity pull everything to earth

1.8 g of ethane gas is used to
boil 200 cm' of water. What
is the number of molecules
of the ethane gas?
[Relative atomic mass of
C = 12 and H = 1, Avogadro
constant = 6.02 x 10^23 mol ]​

Answers

Answer:

3.6 x 10²²molecules

Explanation:

Given parameters:

Mass of ethane gas  = 1.8g

Unknown:

number of molecules of ethane gas = ?

Solution:

To solve this problem, we first find the number of moles of ethane gas.

  Molar mass of ethane, C₂H₆  = 2(12) + 6(1) = 30g/mol

 Number of moles  = [tex]\frac{mass}{molar mass}[/tex]

Insert the parameters and solve;

  Number of moles  = [tex]\frac{1.8}{30}[/tex]   = 0.06mole

 1 mole of a substance contains 6.02 x 10²³ molecules

 0.06mole of ethane will contain 0.06 x 6.02 x 10²³  = 3.6 x 10²²molecules

calculate the pOH of 0.0001 NaOH in water​

Answers

Answer:

pOH = 4

Explanation:

NaOH is a strong base which means that it dissociates completely in water. It will break apart into Na⁺ and OH⁻ ions.

NaOH ⇒ Na⁺ + OH⁻

Because NaOH dissociates completely into its respective ions in water, the moles of NaOH is equal to the moles of hydroxide ions. So, [OH⁻] = 0.0001 M.

Now to find the pOH, use the formula pOH = -log[OH⁻].

pOH = -log[OH⁻]

= -log(0.0001)

= 4

The pOH of the solution is 4.

Hope that helps.

Calculate the concentrations of H3O(+) and SO4(2-) in a solution prepared by mixing equal volumes of 0.2M HCl and 0.6M H2SO4.

Answers

Answer:

[H₃O⁺] = 0.7M

[SO₄²⁻] = 0.3M

Explanation:

The HCl in solution produce 1mole of H₃O⁺ and H₂SO₄ produce 2 moles of H₃O⁺.

When two solutions are mixing in equal volumes, the concentrations of both reactants is halved regard to their initial concentrations. That is:

HCl = 0.1M

H₂SO₄ = 0.3M

And H₃O⁺ will be:

0.1M + 2*0.3M = 0.7M

And SO₄²⁻ comes just from H₂SO₄, that means:

[H₂SO₄] = [SO₄²⁻] = 0.3M

All bacteria contain chromosomes

True
False

Answers

Answer:

True,

Explanation:

doesn't have ends like chromosomes of eukaryotic organisms

so all bacteria contains chromosomes yes, 100%

can i have brainliest i need 2 more to get a new rank tysm


A sample of krypton gas collected at a pressure of 1.31 atm and a temperature of 26.0°C is found to occupy a volume of 23.3 liters

Answers

Mol of Kr gas = 1.244

Further explanation

In general, the gas equation can be written  

PV=nRT

where  

P = pressure, atm  

V = volume, liter  

n = number of moles  

R = gas constant = 0.08205 L.atm / mol K  

T = temperature, Kelvin  

P=1.31 atm

V=23.3 L

T=26+273=299 K

mol of sample :

[tex]\tt n=\dfrac{PV}{RT}=\dfrac{1.31\times 23.3}{0.08205\times 299}=1.244[/tex]

I (1) Did your upper lip area feel warmer or cooler? _____________________

(2) Was the stretching process endothermic or exothermic for the rubber band? ________________

(3) Explain your reasoning.




II
(4) Amount of NaHCO3 used/measured out _______________________ teaspoons

(4a) Observations on Sodium Bicarbonate




(4b) Is sodium bicarbonate water soluble? ______________


(5) Observations on Acetic Acid (vinegar) solution




(6) Observations after the addition of the first tablespoon of vinegar to the sodium bicarbonate




(7) Total amount of HC2H3O2 solution used for the reaction to go to completion _______ tbs


(8a) Overall observations on the reaction. [How was the CO2 gas production observed?]




(8b) How did you determine when the reaction was complete?
(Give at least 2 indications/observations).





(9a). Amount of NaC2H3O2 solid produced _____________________________

(9b) Observations on Sodium Acetate:



(10) Complete the balanced equations for this reaction:

(a) HC2H3O2(aq) + NaHCO3(s)

(b) H2O(ℓ) + NaC2H3O2(aq) heat


(11) Is reaction 10a above a reaction? ___________ How do you know?



If yes, what type/classification? _____________________________


(12) Is reaction 10b above a reaction? ___________ How do you know?



If yes, what type/classification? _____________________________





III (13) Yes or no (before potato)? ____________

(14) Yes or no (after potato)? ___________________

(15) Observations (signs of a reaction occurring):



(16) Potato is ________________________________


(17) Write the reaction here



(18) Type (classification) of reaction ______________________________________



IV (19) Observations on metal (after reaction)





(20) Write the reaction here



(21) Type (classification) of reaction ______________________________________


\

Answers

Answer:

no evidence of how to do the anwsers sorrry.

Explanation:

Imma give 35 points cus I really need it today please.

Answers

Answer:

yes the picture is not clear


In which breaker of water will sugar dissolve fastest?

Answers

Answer: 90

Explanation: Sugar dissolves faster in hot water than it does in cold water because hot water has more energy than cold water. When water is heated, the molecules gain energy and, thus, move faster. As they move faster, they come into contact with the sugar more often, causing it to dissolve faster.

Answer:

90 c

Explanation:

The sugar dissolve in the hottest bc of the heat it will melt in with the water i an pretty sure

The Heat of vaporization for NH3= 1360 J/g. Calculate the quantity of heat energy (in kJ)
needed to completely boil a 155 gram sample at its boiling point
general formula

Answers

Answer:

[tex]Q=210.8kJ[/tex]

Explanation:

Hello!

In this case, since the heat of vaporization is related with the energy required by a substance to undergo the phase transition from liquid to gas, we can compute such amount of energy as shown below:

[tex]Q=m\Delta H_{vap}[/tex]

In such a way, since the enthalpy of vaporization is given as well as the mass, we compute the energy as shown below:

[tex]Q=155g*1360J/g\\\\Q=210.8kJ[/tex]

Best regards!

If 10.0 g of NaF and 15.0 g of HF are dissolved in water to make 2.0 L of solution, what is the pH of the resulting solution?

Answers

Answer:

2.68

Explanation:

Step 1: Calculate the molar concentrations of the solutes

We will use the following expression.

M = mass of solute / molar mass of solute × liters of solution

[HF] = 15.0 g / 20.01 g/mol × 2.0 L = 0.37 M

[NaF] = 10.0 g / 41.99 g/mol × 2.0 L = 0.12 M

Step 2: Calculate the pH of the solution

We have a buffer system formed by a weak acid (HF) and its conjugate base (F⁻ coming from NaF). We can calculate the pH of the solution using Henderson-Hasselbach equation.

pH = pKa + log [F⁻]/[HF]

pH = 3.17 + log (0.12 M/0.37 M)

pH = 2.68

The pH of the resulting solution is 2.68.

What is pH?

pH is potential hydrogen. It is the measurement of the acidity and basicity of any solution.

Step 1: Calculate the molar concentrations of the solutes

M = mass of solute / molar mass of solute × liters of solution

[tex]\rm [HF] = \dfrac{15.0 g}{20.01 g/mol } \times 2.0 L = 0.37 M[NaF] = \dfrac{10.0 g}{ 41.99 g/mol} \times 2.0 L = 0.12 M[/tex]

Step 2: Calculate the pH of the solution

pH = pKa + log [F⁻]/[HF]

pH = 3.17 + log (0.12 M/0.37 M)

Thus, the pH of the resulting solution is 2.68

Learn more about pH

https://brainly.com/question/15289741

#SPJ5

Which phrase best describes soil?​

Answers

Answer:

unconsolidated material that contains nutrient matter and weathered rock

Explanation:

Earth's crust is made up of many layers. The top is soil, which provides the most nutrients for plants, like hummus( The organic nutrient for soil, form from the decaying of plants and animals)

The soil gets its texture from the bedrock, the bottom layer, which weathers, and goes into the soil.

-kiniwih426

1. A sealed 2500mL flask is filled to capacity with 163g of a slimy green liquid. What is the density of the liquid?

Answers

Answer:

0.065 g/mL

Explanation:

The density of a substance can be found by using the formula

[tex]density = \frac{mass}{volume} \\ [/tex]

From the question we have

[tex]density = \frac{163}{2500} \\ = 0.0652[/tex]

We have the final answer as

0.065 g/mL

Hope this helps you

Answer:

Density= mass/volume so 163/2500 = 0.0652

D= 0.0652

Explanation:

__________ is required to make a wave.

Answers

Answer:

The moon is required to make a wave.

If a wave has a period of 0.25 seconds, what is its frequency?

Answers

frequency= 1/period

hence ans= 1/0.25
= 4s

Which TWO statements describe the ocean floor giving brainliest

Answers

Answer:

A & B

Explanation:

Done the Quiz

When you have a two-layer mixture of water and tert-butyl methyl ether, what physical property of these liquids assures you that the ether is the top layer?

Answers

Answer:

The density.

Explanation:

The density is an intensive property of fluids, defined as mass divided by volume.

This property is directly related to the intermolecular forces that are present in the substance: the stronger the intermolecular forces, the higher the density will be, and viceversa. Therefore, organic fluids usually have lower densities than water, because the intermolecular forces in organic fluids are not as strong as in the intermolecular forcer in water (water has very stable hydrogen bonds, whereas organic fluids have van der Waals, weaker than hydrogen bonds).

The liquid that has the lower density will be the the liquid that is on the top layer. In this case, the organic compound tert-butyl methyl ether will be on top of water.

Maalox and Mylanta are both antacids that contain aluminum hydroxide as their active ingredient. Write the balanced equation for the neutralization of hydrochloric acid with aluminum hydroxide, Al(OH)3. Include physical states.

Answers

Answer:

3HCl(aq)+Al(OH)3(s)=AlCl3(aq)+3H2O(l)

Explanation:

This is a double replacement reaction.

Step One: Write down the compound from the name.

Aluminum Hydroxide Al(OH)3

Hydrochloric Acid HCL

Step Two: Perform the double replacement reaction.

AB+CD=AD+CB

Step Three: Balance the equation

Final step: Write in physical states.

The physical state will either be (aq), (s), (l) or (g).

The mass number of a nucleus is the number of: protons nucleons electrons neutrons

Answers

protons

there aint rlly an explanation tbh

Answer:

Nucleons

The mass number of a nucleus is the number of protons and neutrons called the nucleons! Nucleons are the sum of protons and neutrons present in the nucleus of an atom.

Density differences in different materials are able to change the of a wave. A)Amplitude B)Crest C)Speed D)Trough​

Answers

Answer:

C. Speed

Explanation:

Density differences in different materials are able to change the speed of a wave.

Wave speed is dependent on the frequency and wavelength of a wave. As a wave travels from one medium to another, the speed of the wave changes. Speed of a wave is medium dependent. The denser a medium, the slower the speed of waves will be be. A less dense medium will have waves traveling through faster.

Answer:

Speed

Explanation:

The speed or mass of something can totally change the direction of the wave

Alpha decay please help (nuclear chemisty)

Answers

Explanation:

Given reaction:

           ¹⁰⁸₅₃I   →  ⁴₂He   +  ?

 An alpha particle decay requires that the mass number decreases by 4 and atomic number decreases by 2.

This reaction is called  nuclear fission;

  The unknown compound, say Y, will have mass number and atomic number shown below;

               ¹⁰⁸₅₃I   →  ⁴₂He   +  ᵃₙY

Mass number;                  108  =  4 + a

                                               a = 104

Atomic number ;

                                            53  = 2 + n

                                               n = 51

   Y will be      ¹⁰⁴₅₁Y

The atomic number of the new element is 51; so, it is antimony.

               ¹⁰⁴₅₁Sb

   

How do I find the number of moles and molar mass of Gas A and Gas B with the information provided?

Answers

Answer:

A.

Explanation:

hope this helped sorry if its wrong!

Methanol is an alcohol common to alcoholic beverages but toxic if it contains more than 0.4% how much methanol is present in a 750mL solution?

Answers

Answer:

Volume of methanol present in solution = less than 3 ml

Explanation:

Given:

Volume of solution = 750 ml

Find:

Volume of methanol present in solution

Computation:

Volume of methanol present in solution = Volume of solution x 0.4%

Volume of methanol present in solution = 750 ml x 0.4%

Volume of methanol present in solution = 3 ml

Volume of methanol present in solution = less than 3 ml

The amount of methanol present in the 750 mL solution is 3 mL

From the question given above, the following data were obtained:

Percentage of methanol = 0.4%

Volume of solution = 750 mL

Volume of methanol =.?

The volume of methanol present in the 750 mL of solution can be obtained as follow:

Volume = Percent × Volume of solution

Volume of methanol = 0.4% × 750

Volume of methanol = 0.004 × 750

Volume of methanol = 3 mL

Thus, the amount of methanol present in the 750 mL solution is 3 mL

Learn more: https://brainly.com/question/639233

protons
neutrons
atomic symbol
atomic number
chemical element
Atoms are tiny pieces of matter that make up all the substances around you. All atoms
contain one or more positively charged particles called
, which are
found in an atom's nucleus. In many atoms, the nucleus also contains
which have no electrical charge. There are also small, negatively
charged particles called electrons found outside the nucleus. Together, these three types
of particles make up the structure of atoms.
The number of protons in an atom is the atom's
When two atoms
have the same atomic number, they are are classified as the same
All known chemical elements are listed in the periodic table, where they are arranged by
atomic number. The periodic table contains information about each element, often
including a short version of the element's full name called its

Answers

Short version of elements like Carbon which is C and Hydrogen which is H

What kind of change forms a new substance?

A physical change

Answers

Answer:

Chemical change

Explanation: Chemical changes occur when a substance combines with another to form a new substance, called chemical synthesis or, alternatively, chemical decomposition into two or more different substances.

Chemical change ...

Identify ammonia. a. strong electrolyte, strong base b. weak electrolyte, strong base c. strong electrolyte, weak base d. nonelectrolyte e. weak electrolyte, weak base

Answers

Answer:

Ammonia is a weak electrolyte, weak base.

Option e.

Explanation:

Ammonia can take a proton from water to make ammonium.

It is a base, because it takes proton.

When a compound can take protons, we know that is base, according to Bronsted Lowry theory.

We can't describe ammonia as a base, according to Arrhenius, but we know it is base according to Lewis, because the N from the ammonia can be a donor of its electron pair.

It is weak because an small amount of ammonia, can react to produce ammonium, between the protons of water. This is the equilibrium, where the ammonia is considered as the conjugate strong acid of ammonia.

NH₃ +  H₂O  ⇄  NH₄⁺  +  OH⁻     Kb

All the amines are considered as weak bases, because they look like ammonia, where the H of NH₃ are replaced by others chains.

------NH₂

-----NH-----

     

What configuration elements of sodium

Answers

The electron configuration of Sodium (Na) : 1s²2s²2p⁶3s¹

Further explanation

Sodium is an element with the symbol Na and has the atomic number 11. It is located in Group 1 (alkaline) and period 3

atomic number=number of electron=11

In an atom there are levels of energy in the shell and sub shell  

This energy level is expressed in the form of electron configurations.  

Charging electrons in the sub shell uses the following sequence:  

1s², 2s², 2p⁶, 3s², 3p⁶, 4s², 3d¹⁰, 4p⁶, 5s², 4d¹⁰, 5p⁶, 6s², etc.  

So the electron configuration for Natrium ( with 11 electrons) :

1s²2s²2p⁶3s¹ or we can write [Ne] 3s¹

A typical triple bond ________. Group of answer choices consists of six shared electron pairs consists of two σ bonds and one π bond consists of one σ bond and two π bonds consists of three shared electrons is longer than a single bond

Answers

Answer:

One sigma bond and two pi bonds.

Explanation:

Triple covalent bonds between two atoms are created when they share three electron pairs. Three dashes connecting the atoms signify a triple bond. Pnictogen or the nitrogen family of atoms are those having triple valency. The correct option is C.

Two pi bonds and one sigma bond make up a triple bond. One sigma bond and one pi bond make up a double bond. Sigma bonds are usually made up of one atom. A single bond is described as a two-valence electron chemical bond between two atoms.

Covalent bonds with overlapping atomic orbitals fall under the categories of sigma and pi bonds. While pi bonds are created by the lateral overlapping of two atomic orbitals, sigma bonds are created by the head-to-head overlapping of atomic orbitals.

Thus the correct option is C.

To know more about triple bond, visit;

https://brainly.com/question/34048294

#SPJ6

How do u draw an electron dot diagram of an aluminum atom

Answers

Answer:

you tell me

Explanation:

Same $3&:$2!’diwgebjdiwhve
Other Questions
how did farming lead to food surpluses? What is the slip of the line? Identify 3 reasons for the fall of the Old Kingdom. The nation's pork-packing center was located in:A. Kansas CityB. CincinnatiC. ChicagoD. New York Of the girls on the Alden Middle School soccer team, % also play on a travel team. How many of the girls on the middle school team also play on a travel team? What are two activities that might increase your rate of respiration? Avanos no conhecimento cientfico levantaram dvidas sobre as ideias da criao divina e do surgimento da vida por mecanismos no reprodutivos. Em meados do sculo XIX, experimentos cientficos ocasionaram alteraes no entendimento sobre a origem dos seres vivos. Marque a alternativa que contempla o experimento que forneceu evidncias irrefutveis de que os seres vivos surgem somente pela reproduo de seres da mesma espcie. Which of the following best defines the term 'mass'? A. It is the measure of the amount of material an object contains. B. It is the measure of how much matter there is in a specific volume. C. It measures the pull of gravity on an object. D. It measures how quickly an object falls. Below are models of two types of cells. Which of the following structures 2 pointsare common to both cell types?A. mitochondria and vacuolesB. mitochondria and cell wallC. vacuoles and chloroplastsD. cell wall and chloroplasts PMO and LMN are vertical angles. The measure of PMO is (X + 7). The measure of LMN is 55 1. What is the value of x? kwrite a number only) 2. The measure of PMO IS (Write a number only.) Which terms are used in combination to refer to the quadrants of the abdomino-pelvic cavity? front, back, left, right upper, lower, middle, center upper, lower, left, right front, back, middle, center True or false although the pope claimed that he was head of all Christian churches Byzantine thought other bishops were equal to the pope Which of these strategies would eliminate a variable in the system of equations?23 - 5y = 13- 3x + 2y = 13Choose all answers that apply:A. Subtract the bottom equation from the top equation.B. Multiply the top equation by 3. multiply the bottom equation by 2. then add the equations.C. Multiply the top equation by 2, multiply the bottom equation by 3, then add the equations PLEASE HELPPP ASAP 30 POINTSHow did the Industrial Revolution affect the way that people purchased goods?a. Factories made publication of magazines possible.b. Factories made goods more expensive.c. The lower quality of factory goods led to a drop in demand.d. The factory system decreased the cost of goods; transportation advances made delivery easier. The two _______ compared in a ratio are called ______ why does gold sink and wood float when they have similar volumes? please help me out... PLEASE HELP WILL GIVE BRAINLIEST| -10 - (25) | Determine the value of the expression. My teacher said something about absolute value (+8)-(-9)+(-16)-(-4)= 15 points: Is it possible for two numbers to have a difference of 6, and also a sum of 12?T-T please help