Calculate the Ka of a 0.35M weak acid with a pH of 4.2.

Answers

Answer 1

Answer:

Ka = 1.14x10⁻⁸

Explanation:

First we calculate [H⁺] from the pH:

pH = -log[H⁺][H⁺] = [tex]10^{-pH}[/tex][H⁺] = 6.31x10⁻⁵ M

For a monoprotic weak acid, the molar concentration of H⁺ of a solution can be expressed as:

[H⁺] = √(C*Ka)

Where C is the molar concentration of the weak acid solution.

6.31x10⁻⁵ M = [tex]\sqrt{0.35M*Ka}[/tex]1.14x10⁻⁸ = Ka

Related Questions

how many atoms of potassium are in 4.25 g of potassium

Answers

Answer:

6.55 x 10^22 atoms K

Explanation:

Convert from grams to moles (using K molar mass)

K molar mass = 39.098 g/mol

4.25 g K x 1 mol K / 39.098 g K

[grams cancel out]

= 0.1087 mols K

Convert from moles to atoms (using Avogadro's number)

Avogadro's number = 6.0221 x 10^23

0.1087 mols K x 6.0221 x 10^23 atoms K / 1 mols K

[mols cancel out]

= 6.545987 x 10^22

[with proper significant digits.....]

= 6.55 x 10^22 atoms K

differences between geometric isomerism and optical isomerism?​

Answers

Geometric isomers have the same structural formulas but differ in the arrangement of groups at a single atom, at double bonds, or in rings. ... One of the optical isomers rotates the light in one direction, the other rotates the light in the opposite direction but by the same amount.

solve using the distributive property
- 592×7 + 592 × 3​

Answers

Answer:

= -592 (7+3)

= 592 ×10

= -5920

hope it helps u

Mark me brainless

PLEASE HELP ME!
WILL MARK BRAINLIEST

Water Cycle
Listed in the Item Bank are some important labels for sections of the image below. To find out more information about labels, some have more details available when you click on them. Drag and drop each label to the corresponding area it identifies in the image.

Answers

The one on the top left corner is condensation. The one below that is evaporation. The one below that in the water is accumulation. The one next to accumulation is ground flow. The one on the trees is transpiration. The one above transpiration is surface flow. The one above surface flow is precipitation and above precipitation it’s condensation. Lmk if you were able to get that.

HELLP ME PLSSS
The passing of heat through a material is called ________.
A. vibration
B. conduction
C. radiation
D. convectio

Answers

Answer:

B

Explanation:

conduction is the transfer of heat between objects that touch

can someone please do the balanced equation for potassium fluoride?​

Answers

Answer:

K + F2 = KF

Explanation:

Thats the balancee equation for potassium fluoride. The equation is 2K + F2 → 2KF and the balanced equation is K + F2 = KF

=jskidwkjicdovfojvoeeeeeeeeeeeeeeeeeeeeeeeec

Answers

Answer:

you need a theripist or maybe just your girl if this is your question.

Explantion: you are clearly very weird but very cute and ily.

In a receptacle we have 29 g of hydrochloric acid that react with an excess of ammonia according the following equation:
HCl + NH3 → NH4Cl
The percent yield of the reaction is 54 %. Determine:
1.Mass of ammonium chloride obtained.
2.How many moles of ammonium chloride are forme

Answers

Answer:

2969429th Ave

Explanation:

i dont know

Which subatomic particles are transferred in a redox reaction?

Answers

Answer: Electrons

Explanation:

what mix of chemicles gives fireworks thier color: explain for each color

Answers

Answer:

Metal salts commonly used in firework displays include: strontium carbonate (red fireworks), calcium chloride (orange fireworks), sodium nitrate (yellow fireworks), barium chloride (green fireworks) and copper chloride (blue fireworks).

Explanation:

Answer:

Metal salts commonly used in firework displays include: strontium carbonate (red fireworks), calcium chloride (orange fireworks), sodium nitrate (yellow fireworks), barium chloride (green fireworks) and copper chloride (blue fireworks).

The colors are produced by heating metal salts, such as calcium chloride or sodium nitrate, that emit characteristic colors. ... Barium – Barium is used to create green colors in fireworks, and it can also help stabilize other volatile elements. Calcium – Calcium is used to deepen firework colors

which shows a disaccharide

Answers

Answer: It is :B:

Explanation: also sub to technoblade

How many grams of Ni are formed from 55.3 g of Ni2O3?

2Ni2O3(s)⟶4Ni(s)+3O2(g)

Answers

Answer:

39.2 g

Explanation:

2Ni₂O₃(s) ⟶ 4Ni(s) + 3O₂(g)

First we convert 55.3 grams of Ni₂O₃ into moles of Ni₂O₃, using its molar mass:

55.3 g ÷ 165.39 g/mol = 0.334 mol Ni₂O₃

Then we convert 0.334 moles of Ni₂O₃ into moles of Ni, using the stoichiometric coefficients of the balanced reaction:

0.334 mol Ni₂O₃ * [tex]\frac{4molNi}{2molNi_2O_3}[/tex] = 0.668 mol Ni

Finally we calculate how much do 0.668 Ni moles weigh, using the molar mass of Ni :

0.668 mol Ni * 58.69 g/mol = 39.2 g

Uranium is an element with three naturally occurring isotopes: 238U, 235U, and 234U. This means that 238U, which has a mass number of 238 has _______more than 235 u which has a mass number of 235.

Answers

Answer:

The correct answer is - neutrons.

Explanation:

Uranium has various isotopes found naturally that are three 238U, 235U, and 234U. Uranium has an atomic number of 92 which means there are 92 protons and 92 electrons in the atomic structure.

Isotopes have the same number of protons but a different number of neutrons that can vary from 141 to 146. U-238 has 146 neutrons in the nucleus, whereas 235 U has 143 neutrons.

The U- 238 has more neutrons than U- 235. Atomic mass is the sum total of the nucleons or protons and neutrons.

What are Isotopes?

They are the different variants of the same molecules which have the same number of protons but the different number of neutrons.

Atomic mass is the sum total of the nucleons or protons and neutrons. The atomic number of Uranium is 92, the rest of the mass comes from neutrons.

Therefore, the U- 238 has more neutrons than U- 235.

Learn more about Isotopes:

https://brainly.com/question/9099776

To lower the chance of suffering from decompression sickness (the bends), scuba divers use a mixture of gases in their air tank (typically oxygen and nitrogen gas in recreational dives). Assuming no other gas is present besides oxygen and nitrogen, if the mole fraction of oxygen present is 0.21, what is the partial pressure of nitrogen gas if the total pressure is 111.7 atm

Answers

Answer: The partial pressure of nitrogen gas if the total pressure is 111.7 atm is 88.243 atm.

Explanation:

Given: Mole fraction of oxygen = 0.21

Total pressure = 111.7 atm

It is known that the sum of moles fractions is always equal to 1. So, mole fraction of nitrogen is calculated as follows.

Mole fraction of nitrogen + mole fraction of oxygen = 1

Mole fraction of nitrogen = 1 - mole fraction of oxygen

Mole fraction of nitrogen = 1 - 0.21

Mole fraction of nitrogen = 0.79

Now, formula used to calculate the partial pressure of nitrogen is as follows.

[tex]P_{N} = X_{N} \times P_{total}[/tex]

where,

[tex]P_{N}[/tex] = partial pressure of nitrogen

[tex]X_{N}[/tex] = mole fraction of nitrogen

[tex]P_{total}[/tex] = total pressure

Substitute the values into above formula as follows.

[tex]P_{N} = X_{N} \times P_{total}\\= 0.79 \times 111.7 atm\\= 88.243 atm[/tex]

Thus, we can conclude that the partial pressure of nitrogen gas if the total pressure is 111.7 atm is 88.243 atm.

by what process does water vapor become a cloud?
a. evaporation
b. transpiration
c. condensation
d. precipitation

Answers

the answer is c. condensation
The answer is evaporation

A 0.227 mol chunk of dry ice (solid CO2) changes to gas. What is the volume of that gas measured at 27 °C and 740 mmHg?

Answers

Answer:

Explanation:3.2 ft 2 fti2 ft 4 ft ft2

Determine what mass of carbon monoxide and what mass of hydrogen are required to form 6.0 kg of methanol by the reaction CO(g) + 2H2(g) -> C H3OH(l)

Answers

Answer:

5250 grams or 5.25 kg of carbon monoxide and 375 grams of hydrogen are required to form 6 kg of methanol.

Explanation:

The balanced reaction:

CO (g) + 2 H₂ (g) -> CH₃OH (l)

By stoichiometry of the reaction, the following amounts of moles of each compound participate in the reaction:

CO: 1 moleH₂: 2 molesCH₃OH: 1 mole

Being the molar mass of each compound:

CO: 28 g/moleH₂: 1 g/moleCH₃OH: 32 g/mole

By reaction stoichiometry, the following mass quantities of each compound participate in the reaction:

CO: 1 mole* 28 g/mole= 28 gramsH₂: 2 moles* 1 g/mole= 2 gramsCH₃OH: 1 mole* 32 g/mole= 32 grams

Being 6 kg equivalent to 6000 grams (1 kg= 1000 grams), you can apply the following rules of three:

If by stoichiometry 32 grams of methanol are formed from 28 grams of carbon monoxide, 6000 grams of methanol are formed from how much mass of carbon monoxide?

[tex]mass of carbon monoxide=\frac{6000 grams of methanol*28 grams of carbon monoxide}{32 grams of methanol}[/tex]

mass of carbon monoxide= 5250 grams= 5.25 kg

If by stoichiometry 32 grams of methanol are formed from 2 grams of hydrogen, 6000 grams of methanol are formed from how much mass of hydrogen?

[tex]mass of hydrogen=\frac{6000 grams of methanol*2 grams of hydrogen}{32 grams of methanol}[/tex]

mass of hydrogen= 375 grams

5250 grams or 5.25 kg of carbon monoxide and 375 grams of hydrogen are required to form 6 kg of methanol.

When the ball is at rest, what forces are acting on it?

Answers

When a ball is at rest it is acted on by an unbalanced force.

What is the volume, in cubic meters, of an object that is 0.21 m long, 4.7 m wide, and 5.3 m high?

Answers

Answer:

The formula for volume of a rectangle is length multiply by width multiply thus, 0.25 m multiply 6.1 m multiply by 4.9 m = 7.5m^3.

Explanation:

the least number of significant figures is 2 thus the final answer will have the same number of significant figures. 7.5m^3

Hydrogen iodide can decompose into hydrogen and iodine gases. 2HI(g) H2(g) I2(g) K for the reaction is 0.016. Of 0.148 atm of HI(g) is sealed in a flask, what is the pressure of each gas when equilibrium is established

Answers

Solution :

Given :

Hydrogen iodide decomposes to hydrogen and iodine gas

    [tex]$2 HI \ \ \ \Leftrightarrow \ \ \ \ H_2 \ \ \\ + \ \ I_2 $[/tex]

I    0.148            0          0

C     -2a           +a          +a

E  0.148-2a      a            a

We know

[tex]$k_p=\frac{P(H_2)P(I_2)}{P(HI)^2}$[/tex]

[tex]$0.016=\frac{a^2}{(0.148-2a)^2}$[/tex]

[tex]$0.016^{1/2}=\frac{a}{0.148-2a}$[/tex]

[tex]$0.12649=\frac{a}{0.148-2a}$[/tex]

0.0187 = 1.2529 a

a = 0.0149

Therefore

P(HI) = 0.148 - 2a

        = 0.148 - 2(0.0149)

        = 0.1182 atm

P([tex]$H_2$[/tex]) =  a

        = 0.0149 atm

P([tex]$I_2$[/tex]) =  a

        = 0.0149 atm

A chemical equilibrium exists when: A chemical equilibrium exists when: there are equal amounts of reactants and products. the rate at which reactants form products is the same as the rate at which products form reactants. the sum of reactant and product concentrations equals one mole. reactants are completely changed to products. the rate at which reactants form products becomes zero.

Answers

Answer: A chemical equilibrium exists when the rate at which reactants form products is the same as the rate at which products form reactants.

Explanation:

When the concentration of both the reactants and products do not change with time then it means the chemical reaction has reached to a state of chemical equilibrium.

For example, [tex]CO(g) + Cl_{2}(g) \rightleftharpoons COCl_{2}(g)[/tex]

Therefore, we can conclude that a chemical equilibrium exists when the rate at which reactants form products is the same as the rate at which products form reactants.

A 5.0 L sample of gas at 300. K is heated to 600. K. What will the new volume of the gas be?

Answers

Answer:

[tex]V_2=10L[/tex]

Explanation:

Hello there!

In this case, according to the given information, it turns out possible for us to calculate the required new volume by using the Charles' law as a directly proportional relationship between temperature and volume:

[tex]\frac{V_2}{T_2} =\frac{V_1}{T_1}[/tex]

In such a way, we solve for V2 and plug in V1, T1 and T2 to obtain:

[tex]V_2=\frac{V_1T_2}{T_1}\\\\V_2=\frac{5.0L*600K}{300K}\\\\V_2=10L[/tex]

Regards!

Which of the first four radioisotopes in the decay series has the longest half-life? Pa-234 Th-234 U-234 U-238

Answers

Answer:

can u explain a little more then i will help like what are the four

Explanation:

Answer:

d) U-238

Explanation:

edg 2021

The oceanic crust is destroyed at convergent boundaries because it_______________________ *
a) diverges to form a rift valley
b) goes into a subduction zone where it is melted by the hot magma
c) transforms
d) the rock crumbles at an ocean ridges

Answers

Answer: I believe the answer is d)  the rock crumbles at an ocean ridges

Explanation:

balance the equation P + O2 → P4O10

Answers

The answer is: 4P + 5O2 —> P4O10

How many sigma and pie bonds are in the following compound?
1.00
on
H:0:
| ||
H-C-C-H
1
H

Answers

For the first

H : O : H

Theres two bonds here

Each other are sigma

So 2Sigma bonds present

For the Second

I believe you wanted to write Ethyne....

In a triple bond... Theres 1sigma and 2 Pi bonds

Every single bond is a sigma bond

So

Counting all

we have

2Pi bonds and 3Sigma bonds

PLS HELP ASAP I ONLY HAVE 7 min
On which of the following factors does the amount of energy absorbed by an endothermic reaction depend?

1. Number of reactants
2. Physical state of the reactant
3. Sum of the potential energy of the reactants and products
4. Difference in the potential energy of the reactants and products

Answers

Answer:

Option 3 and 4

Explanation:

In an endothermic reaction, the potential energy of the system increase. The potential energy of the reactant is less as compared to the potential energy of the products and hence additional energy is required to produce products.

The potential energy of the reactants depend on their chemical state and not the physical state. Hence, option 2 is not correct. Also, the number of reactant do not make any significant impact on the determination of potential energy of reactants. Thus, option 1 is also incorrect

Control rods in nuclear reactors are made of materials that absorb free neutrons in order to
slow down the chain reaction.
True
False

Answers

The answer to your question would be: true
The answer is A. true

Andrea is making a poster to show how the nervous system uses signals to send information through the body. These signals are sent through nerves. What parts should Andrea include in her diagram of a nerve as evidence to support her explanation?



neurons only


neurons, axons, and dendrites


dendrites, blood vessels, and muscle cells


axons, blood vessels, and connective tissue

Answers

Answer:b

Explanation:

How is water important to many branches of science?

Answers

Answer:

Water is capable of dissolving a variety of different substances, which is why it is such a good solvent. And, water is called the "universal solvent" because it dissolves more substances than any other liquid. This is important to every living thing on earth.

Other Questions
What is the equation of a circle with center (-2,3) and radius 4? A. (x + 2)2 +- 3)2 = 16 O B. (x + 2)2 + (y - 3)2 = 4 O C. (x-2)2 + (y + 3)2 = 16 D. (x + 2)2 = (y - 3)2 = 16 What is the vertex of the function f(x) = x2 + 12x?O (-6, -36)O (-6, 0)O (6,0)O (6, -36) Help?!?!?!?!?!?!?!?!?!?!?!? Joe Sullivan and Mark Holland, members of the top management at EuAir, a European airlines, were preparing for a meeting to discuss strategies to combat the recent rise in fuel prices. Before the meeting began, Joe and Mark were discussing how oil prices significantly impact the health of the world economy. Joe spoke of how higher oil prices since 1999, partly the result of OPEC supply management policies, contributed to the global economic downturn in 2000-2001 and have not been stable since. Mark agreed but added that the right kind of strategy could help them overcome this challenge, and that they could even use the situation to hike fares and generate additional revenues. Which of the following statements, if true, would denote the occurrence of groupshift in Mark's opinions during the meeting?A) Mark proposed that the prices be hiked and additional customer service measures be included so costumers have the best experience flying with EuAir. B) Mark encouraged the top-management team to consider laying off surplus employees and rightsizing EuAir to enhance its efficiency and lower costs. C) Mark agreed with Joe's opinion that providing the best service possible, even if it meant incurring a loss in the short run, would be the best strategy. D) Mark felt that EuAir should suspend some of its less profitable flights in the short run in favor of the routes that have greater demand among consumers. E) Mark proposed that this was an opportunity for EuAir to use its brand name effectively and diversify into other products and services. Compared to developing nations, developed nations have A higher health standards. B greater personal wealth. C lower health standards. D faster-growing populations. What is the value of p?O 6O 70809 Answer the questions based on the ad (answer the questions in spanish)1. How much do the shirts cost?2. How much do the t-shirts cost?3. When does the offer start and end?4. What is the name of the clothing store?5. What do you think Your cowboy look, at a great price means?6. Who would be most interested in this advertisement? Why do you think?7. In what country do you think this store is located? Why? Cite evidence from the ad what social impact does racism have in the U.S? Round 51354 to the nearest thousand. I didn't mean to press that answer but please help. Shades are darker that are created by mixing a ___________ with a color. is the practice of making contact and exchanging information withother people or groups.A. InterningB. Community serviceO c. NetworkingO D. A job shadow 20 points. Help. No links. Ty :) What is the present form of government in Suriname? O democracy dictatorship monarchy O republic The ratio of footballs to total pieces of equipment is... and we have 2 baseballs and 6 footballs The U.S. Constitution:Question 6The English Bill of Rights, which gave the people the right to petition theking, the right to bear arms and freedom from cruel and unusualpunishment, emphasized what political concept?Select one:separation of powersrule of lawnatural rights or individual rightsOpopular sovereignty Why is Dalton's Gas Law a problem for people who visit high altitudes? x-7y=4,5x-4y=-11 solve system of equations by substitution Felicia and Tom went out on their first date, and at the conclusion of their evening Tom invited Felicia to come to his apartment for a drink. She liked him and felt inclined to do so. Once Felicia was inside she sat down and made herself comfortable while Tom prepared some mixed drinks. When he came back into the room he turned the lights off and snuck up behind Felicia to blindfold her. She screamed. He ripped her clothing off and engaged in sexual activity with her while she was physically attempting to fight him off. This is an example of what Paradise Corporation budgets on an annual basis for its fiscal year. The following beginning and ending inventory levels (in units) are planned for next year. Beginning Inventory Ending Inventory Raw material* 30,000 40,000 Finished goods 70,000 60,000 * Three pounds of raw material are needed to produce each unit of finished product. If Paradise Corporation plans to sell 510,000 units during next year, the number of units it would have to manufacture during the year would be: