A buffer solution of volume 0.500 L contains 1.68 g NH3and 4.05 g (NH4)2SO4.

Required:
a. What is the pH of this solution?
b. If 0.88 g of NaOH is added to the solution, what will be the pH?

Answers

Answer 1

Answer:

wait

Explanation:

Answer 2

a. The pH of this solution is 9.45.

b. If 0.88 g of NaOH is added to the solution, the pH will be  9.74.

What is pH means?

a way to gauge how basic or acidic a material or solution is. On a scale of 0 to 14, pH is measured. A pH of 7 indicates neutrality on this scale, which implies it is neither acidic nor basic. More basic substances have a pH value more than 7, whereas more acidic substances have a pH value less than 7.

first of all we should calculate the molarity of the compounds

no. of moles of NH₃ = weight / molecular weight = 1.68 / (14+3) = 0.099

no. of moles of (NH₄)2SO4 = 4.05 / {2×(14+4) + 32 + 64} = 0.031

no. of moles of NH4+ = 2×0.031 = 0.062

[NH₃] = no. of moles / volume(L) = 0.099/ 0.5 = 0.198

[(NH₄⁺] = 0.031/0.5 = 0.124

1) now we know that

pH + pOH = pkw

pOH = pkw - pH = 14 - pH ---- -1

also

pOH = pkb + log ( [salt]/[base])

from 1

14 - pH = pkb + log ( [salt]/[base])

putting values

14- pH = -log(1.8e-5) + log(0.124/0.198)

14 - pH = 4.54

pH = 9.45

2) if 0.88g NaOH is added then as we know that NaOH is a base then it will reduce the buffer capacity

as there would be OH- ions initially present

hence the buffer action will move backward

i.e

pOH = pkb + log {(salt-x) / (base+x)}

where x= molarity of NaOH

no of moles of NaOH = 0.88 / (23+16+1) = 0.022

molarity of NaOH = 0.022/0.5 = 0.044

then 14 - pH = -log(1.8e-5) + log{ (0.124-0.044) / (0.198+0.044) }

14 - pH = 4.26

pH = 9.74

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Related Questions

2. Which of the following is NOT a necessary input for the process of photosynthesis?
A. CO2 (carbon dioxide)
B. Sunlight
C. H20 (water)
D. O2 (oxygen)

Answers

The answer would be option A. This is because CO2 or carbon dioxide is an output rather than an input. I hope this helped!

The answer option which is not a necessary input for the process of photosynthesis is: D. [tex]O_2[/tex] (oxygen)

Photosynthesis can be defined as a biological and chemical process through which living organisms such as green plants, transform light energy (sunlight) into chemical energy.

Basically, both sunlight, carbon dioxide ([tex]C0_2[/tex]) and water ([tex]H_2O[/tex]) contained in the Earth's atmosphere plays a significant role in photosynthesis because they serve as an input.

Hence, the necessary input for the process of photosynthesis to take place include the following:

Water ([tex]H_2O[/tex]) Sunlight (light energy).Carbon dioxide ([tex]C0_2[/tex]).

In conclusion, [tex]O_2[/tex] (oxygen) is an end product (output) of photosynthesis rather being an input.

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Is SO3 ionic or ionic using the stock system or molecular

Answers

Answer:

Molecular

Explanation:

Using the rules for the nomenclature for naming binary covalent (molecular) compounds, the compound SO3 is named sulfur trioxide. The prefix tri- indicates that the oxygen has a subscript of 3 and that a molecule of sulfur trioxide has three oxygen atoms.

How do hurricanes form? How do hurricanes form?

a Hurricanes form when winds circulate about a column of cool air.

b Hurricanes form when two warm fronts meet over the ocean

c Hurricanes form when warm air over the equator mixes with cold air from the poles

d Hurricanes form as a result of rising warm air and circulating winds​

Answers

I think the answer is D

Answer:

D. Hurricanes form as a result of rising warm air and circulating winds​

Explanation:

Tumu’s class was given an assignment to feature a scientist that contributed to the development of the cell theory. The class decided to use images to feature the scientist of their choice.

Which image would Tumu most likely use in his assignment to feature Rudolf Virchow?

the magnified shapes of cells in a piece of cork
the different cells that make up a plant leaf
the types of cells at work in the human body
the way root cells reproduce to increase root length

Answers

Answer:

The types of cells at work in the human body

Explanation:

Rudolf Virchow was a German physician who is known as the father of modern pathology. He contributed to the development of the cell theory by concluding that all cells come from preexisting cells. This led to the conclusion that diseases occur at the cellular level, which allowed scientists to diagnose diseases more accurately.

Considering that Virchow analyzed human cells, the image that Tumu would be most likely to use in his assignment is the one of the types of cells at work in the human body.

Answer:

D the way root cells reproduce to increase root length

Explanation:

Have a good day!

Please help on the image below.

Answers

Heat capacity of Calorimeter = 10.7 J/°c

Further explanation

Heat lost=Heat gained

Q in = Q out

-Q lost(hot water)=Q gained (cold water+calorimeter)

-m.c.Δt=m.c.Δt+C.Δt

[tex]\tt \rightarrow -50\times 4.18\times (32.7-43)=50\times 4.18\times (32.7-22.9)+(32.7-22.9)\times C_{cal}\\\\\rightarrow 2152.7=2048.2+9.8\times C_{cal}\\\\104.5~J=9.8\times C_{cal}\\\\C_{cal}=\dfrac{104.5}{9.8}=10.7~J/^oC[/tex]

The mass of 900. atoms of sodium(Na)

Answers

Answer:

3.44 × 10⁻²⁰ g Na

General Formulas and Concepts:

Chemistry - Atomic Structure

Reading a Periodic TableUsing Dimensional AnalysisAvogadro's Number - 6.022 × 10²³ atoms, molecules, formula units, etc.

Explanation:

Step 1: Define

900 atoms Na

Step 2: Identify Conversions

Avogadro's Number

Molar Mass of Na - 22.99 g/mol

Step 3: Convert

[tex]900 \ atoms \ Na(\frac{1 \ mol \ Na}{6.022 \cdot 10^{23} \ atoms \ Na} )(\frac{22.99 \ g \ Na}{1 \ mol \ Na} )[/tex] = 3.4359 × 10⁻²⁰ g Na

Step 4: Check

We are given 3 sig figs. Follow sig fig rules and round.

3.4359 × 10⁻²⁰ g Na ≈ 3.44 × 10⁻²⁰ g Na

Which of these statements best answers the question: What is art?

Answers

Answer:

You didn't provide any statements. If it is an option, art is a form of expression. Something created from imagination that expresses the thoughts and emotions of the artist.

The statement that best answers the question: What is art is that—Art is a form of visual language. Therefore, the correct option is A.

What is an art?

Art is a diverse range of human activities and products that are created with the intention of expressing the imagination, emotions, or ideas, or to make a statement, in a visually appealing way.

Art can take many forms, including visual arts (such as painting, sculpture, and photography), performing arts (such as music, dance, and theater), and literary arts (such as poetry and prose).

It is typically seen as a form of communication and can be used to convey ideas, emotions, or political, social or cultural messages. It can also be used to simply evoke a response or emotion in the viewer, or to create a sense of beauty or aesthetic enjoyment. Therefore, the correct option is A.

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The question is incomplete, but most probably the complete question is,

Which of these statements best answers the question: What is art?

A. Art is a form of visual language.

B. Art is a form of written language.

C. Art is a form of spoken language.

D. Art is a form of dance language.

Identify the titration curve for a monoprotic weak acid titrated with a strong base.

Answers

Answer:

Titration is a technique to determine the concentration of an unknown solution. As illustrated in the titration setup above, a solution of known concentration (titrant) is used to determine the concentration of an unknown solution (titrand or analyte).

Typically, the titrant (the solution of known concentration) is added through a burette to a known volume of the analyte (the solution of unknown concentration) until the reaction is complete. Knowing the volume of titrant added allows us to determine the concentration of the unknown analyte. Often, an indicator is used to signal the end of the reaction, the endpoint. Titrant and analyte is a pair of acid and base. Acid-base titrations are monitored by the change of pH as titration progresses.

Let us be clear about some terminologies before we get into the discussion of titration curves.

An object has a mass of 3.50 grams and a density of 5.61 g/mL. What is the volume of this object? *

Answers

Answer:

0.62 mL

Explanation:

The volume of a substance when given the density and mass can be found by using the formula

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

From the question we have

[tex]volume = \frac{3.50}{5.61} \\ = 0.6238859...[/tex]

We have the final answer as

0.62 mL

Hope this helps you

Easy Mole Conversion:

How many grams are in 2.00 moles of cobalt (I) hydroxide?

Answers

Answer:

Mass = 185.896 g

Explanation:

Given data:

Mass in gram = ?

Number of moles = 2.00 mol

Solution:

Formula:

Number of moles = mass/molar mass

Molar mass of cobalt (I) hydroxide =92.948 g/mol

by putting the values,

2.00 mol = Mass/92.948 g/mol

Mass = 2.00 mol × 92.948 g/mol

Mass = 185.896 g

How many kilpgrams are in 2.71x10^22 molecules of CO2

Answers

Answer:

mass of 1 molecule of CO2=44 g

mass of 2.71*10^22 of CO2=2.71*10^22*44=1.2*10^24g

now to convert grams into kilogram we know that

1000 g=1kg

1.2*10^24=1.2*10^24/1000=1.2*10^21

According to Avogadro's number concept,there are 1.979×10[tex]^-3[/tex] kilograms in 2.71 ×10²² molecules of CO₂.

What is Avogadro's number?

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. Mass is calculated as, number of molecules/Avogadro's number×molar mass

Substitution in above formula gives, mass=2.71×10²²/6.023×10²³×44=1.979 g or 1.979×10[tex]^-3[/tex] kg.

Thus, there are  1.979×10[tex]^-3[/tex] kg in 2.71×10²² molecules of carbon dioxide.

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What is the mass, in grams, of 2.3 moles of gold?

Answers

Answer:

453.031g

Explanation:

atomic mass (molar mass)- 196.97g/m

2.3(196.97)=453.031

Question 1 of 10
In which state of matter do the particles move independently of one another?
A. Amorphous solid
B. Gas
C. Crystalline solid
D. Liquid

Answers

Liquid because objects are all together

Answer:

Gas (B)

Explanation:

Which numerical setup can be used to calculate the
atomic mass of the element bromine?

Answers

Answer:

From the numerical steps highlighted under explanation, the average atomic mass of bromine is 79.91 u

Explanation:

The steps to be taken will involve;

1) Find the number of isotopes of bromine.

2) Identify the atomic mass and relative abundance of each of the isotopes.

3) Multiply the atomic mass of each of the isotopes by their corresponding values relative abundance value.

4) Add the value in step 3 above to get the average atomic mass of bromine.

Now;

Bromine has 2 isotopes namely;

Isotope 1: Atomic mass = 78.92amu and a relative abundance of 50.69%.

Isotope 2: Atomic mass = 80.92amu and a relative abundance of 49.31%.

Using step 3 above, we have;

(78.92 × 50.69%)

And (80.92 × 49.31%)

Using step 4 above, we have;

(78.92 × 50.69%) + (80.92 × 49.31%) ≈ 79.91 u

The atomic mass of bromine has been calculated as 79.9062 amu.

The relative atomic mass of the element has been given as the mass of each isotope with respect to their abundance.

The atomic mass has been given as:

[tex]amu=\sum mass\;\times\;\% Abundance[/tex]

The available isotopes of Bromine have been:

Isotope 1 = 78.92 amu, and 0.5069 % abundance

Isotope 2= 80.92 amu, and 0.4931 % abundance

Submitting the values for the atomic mass unit of bromine ([tex]amu_{\text{Br}}[/tex]):

[tex]amu_{\text {Br}}= (78.92\;\times\;0.5069)\;+\;(80.92\;\times\;0.4931)\\amu_{\text{Br}}=40.0045\;+\;39.9016\\amu_{\text{Br}}=79.9062[/tex]

The atomic mass of bromine has been calculated as 79.9062 amu.

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what is the device to use to measure a potential difference in a circuit called?

Answers

Voltmeter.
would be correct

Answer:

c. Voltmeter

Explanation:

PLATO LIVES MATTER

6.0 L of a gas exert a pressure of 2.5 atm. When the pressure is increased 2 points
to 10.0 atm, what is the new volume of the gas?
O 1.0L
O 1.5L
O 1.7L
O 25L

Answers

25L hope this helps.

2. Combining 0.242 mol Fe2O3 with excess carbon produced 10.2 g Fe.

Fe2O3+3C⟶2Fe+3CO

(a) Actual yield of Fe mole

(b) percentage mole

(c) theoretical yield of iron mmoles

Answers

actual yield = 0.182 mole

theoretical yield : 0.484 mole

percentage mole(% yield)=37.6%

Further explanation

Percent yield is the comparison of the amount of product obtained from a reaction with the amount you calculated

General formula:

Percent yield = (Actual yield / theoretical yield )x 100%

An actual yield is the amount of product actually produced by the reaction. A theoretical yield is the amount of product that you calculate from the reaction equation according to the product and reactant coefficients

Reaction

Fe₂O₃+3C⟶2Fe+3CO

a. actual yield of Fe mole

10.2 g produced

[tex]\tt mol~Fe=\dfrac{10.2}{56}=0.182[/tex]

b. percentage mole and theoretical yield

0.242 mol Fe₂O₃ = 2 x 0.242 mol Fe = 0.484 mol (theoretical yield)

percentage yieldpercentage mole)

[tex]\tt \dfrac{0.182}{0.484}=0.376=37.6\%[/tex]

How does body temperature, energy level, and water level affect a person’s ability to survive?

Answers

U won’t get hyperthermia or a heat stroke when ur hot u use up more energy but when ur cold u use up less

Urgent help me please answer it if you know it

Answers

i think it is c.

i know that plants take in co2 to then make oxygen and they need water and sunlight to grow and live.

Identify the molecule with the strongest intermolecular force.

C6H6
OF2
CHCl3
H2O

Answers

Answer:

C6H6 has the strongest intermolecular force

i think

Answer:

H2O

Explanation:

Because it is a hydrogen bond which is said to be the strongest bond between the H and a N,O, or F combination

Which of the following is chemical property?
Question is in the picture help ASAP please

Answers

Answer:

C

Explanation:

Whats the answer 50 points and brainliest if its right

Answers

Answer:

D

Explanation:

Which pair of elements would you expect to have similar properties?
Li and Fe
At and F
F and o
Ge and As

Answers

The answer to your question is F and O they are in the same GROUP meaning side ways <>

How many grams of oxygen gas will be produced when 2.50 moles of potassium chlorate is decomposed?

Answers

Answer:

[tex]m_{O_2}=120gO_2[/tex]

Explanation:

Hello!

In this case, since the decomposition of potassium chlorate is:

[tex]2KClO_3\rightarrow 2KCl+3O_2[/tex]

We can see a 2:3 mole ratio between potassium chlorate and oxygen (molar mass 32.0 g/mol), thus, via stoichiometry, we compute the mass of oxygen that are produced by the decomposition of 2.50 moles of this reactant:

[tex]m_{O_2}=2.50molKClO_3*\frac{3molO_2}{2molKClO_3} *\frac{32.0gO_2}{1molO_2}\\\\m_{O_2}=120gO_2[/tex]

Best regards!

Calculate the pH after 20.0% (by moles) of the benzoic acid is converted to benzoate anion by addition of a strong base. Use the dissociation equilibrium to calculate the pH. pH = ________

Answers

Answer:

pH = 4.79

Explanation:

The equilibrium of benzoic acid, BH, is:

BH ⇄ B⁻ + H⁺

Where B⁻ is benzoate anion

Where the dissociation equilibrium, Ka, is:

Ka = 6.46x10⁻⁵ = [B⁻] [H⁺] / [BH]

If 20.0% is B⁻, 80.0% is BH, replacing:

6.46x10⁻⁵ = [20.0%] [H⁺] / [80.0%]

1.615x10⁻⁵ = [H⁺]

As pH = -log [H⁺]

pH = 4.79

Which products are formed when aluminum is added to a silver chloride solution? Use the activity series below if needed. Al> Mn > Zn>.Cr > Fe > Cd> Co > Ni > Sn > Pb>H> Sb > Bi > Cu> Ag > Pd >Hg > Pt O none O only AICI3 O AlCl3 and Ag O AIAg3 and Cl2​

Answers

Answer:

AlCl3 and Ag

Explanation:

Edge 2020

The products formed when aluminum is added to a silver chloride solution are "AlCl3 and Ag".

The reaction of aluminum and silver chloride is a single substitution type of reaction that is expressed as follows: Al (s) + 3AgCl (aq) = AlCl3 (aq) + 3Ag (s)When aluminum is added to the silver chloride solution, the cations are exchanged in the process forming AlCl3 and Ag.

Chemical reaction, a process in which one or more substances, the reactants, are converted to one or more different substances, the products. Substances are either chemical elements or compounds. A chemical reaction rearranges the constituent atoms of the reactants to create different substances as products.

Chemical reactions are an integral part of technology, culture, and indeed of life itself. Burning fuels, smelting iron, making glass and pottery, brewing beer, and making wine and cheese are among many examples of activities incorporating chemical reactions that have been known and used for thousands of years. Chemical reactions abound in the geology of Earth, in the atmosphere and oceans, and in a vast array of complicated processes that occur in all living systems.

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During bromination using NBS, the addition product is not observed because the rate of addition is _______than the rate of the chain propagation steps.

Answers

Answer:

slower

Explanation:

NBS is used in place of Br2 during bromination because the use of Br2 tends to result in the formation of a large concentration of the addition product.  This is because, the Br2 interacts with the double bond to yield only the dibromide (addition product).

The usefulness of NBS lies in the fact that it provides a lower concentration of Br2, and such that the rate addition is slower than the chain propagation steps. Only the monobromination product is observed

The low concentration of Br2 allows the free-radical reaction to out-compete the alkene addition reaction.

From the following heats of reaction,
2C (graphite) + H2 (g) -->C2H2 (g) H = 227 kJ
6C (graphite) + 3H2 (g) -->C6H6 (l) H = 49 kJ
calculate the heat for the reaction
3C2H2 (g) -->C6H6 (l)
A. 26.7 kJ
B. -26.7 kJ
C. -178 kJ
D. 178 kJ
E. -632 kJ
F. 632 kJ

Answers

Answer:+178

Explanation:

The heat of the reaction for the following reactions is 178 kJ. the correct option is D.

What is the heat of the reaction?

The heat that is added or removed during a chemical reaction is called the heat of reaction.

It is also called the enthalpy of the reaction.

The heat is absorbed or released to maintain the temperature of the reaction.

The enthalpy can be calculated by subtracting the enthalpy of the product from the enthalpy of the reactant.

Thus, the correct option is D.

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if a student added water to her cola what change would you expect to see in the ph level

Answers

Answer:

You would expect it to go down

Explanation:

This is because she is essentially watering down, causing the Ph level to go down too.

If a student added water to her cola, then the pH level is low. This is due to the fact that she is essentially diluting, which lowers the pH level as well.

What is pH ?

The pH scale determines how acidic or basic water is. The range is 0 to 14, with 7 representing neutrality. Acidity is indicated by pH values below 7, whereas baseness is shown by pH values above 7. In reality, pH is a measurement of the proportion of free hydrogen and hydroxyl ions in water.

pH stands for "Potential of Hydrogen" in its full form. The negative logarithm of the concentration of H+ ions is known as pH. As a result, the meaning of pH is defined as the strength or power of hydrogen.

A solution's pH is a significant indicator of its chemical composition. The pH can affect how readily available nutrients are, how biological processes work, how bacteria behave, and how chemicals behave.

Thus, If a student added water to her cola, then the pH level is low.

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The density of osmium (the densest metal) is 22.57 g/cm3.
What is the mass of a block of osmium with dimensions:
4.22 cm x 3.62 cm x 1.41 cm?

Answers

Answer:  mass = 485 grams approximately

=======================================================

Work Shown:

First we need the volume of the block

volume = (length)*(width)*(height)

volume = (4.22)*(3.62)*(1.41)

volume = 21.539724

volume = 21.5 cubic cm

I'm rounding to three sig figs because each of the dimensions are to three sig figs.

--------------------------

Now turn to the formula

density = mass/volume

This can be rearranged to

mass = density*volume

Plug in the given density and the volume we found earlier to get

mass = density*volume

mass = (22.57)*(21.5)

mass = 485.255

mass = 485 grams

I'm rounding to three sig figs because it's the smaller sig fig count of 22.57 and 21.5

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