What mass of NaOH would need to be dissolved in 500.0 mL of water to produce a solution with a pH of 12.40

Answers

Answer 1

Answer:

0.5024 g

Explanation:

Step 1: Calculate the concentration of H⁺

We will use the definition of pH.

pH = -log [H⁺]

[H⁺] = antilog -pH = antilog -12.40 = 3.981 × 10⁻¹³ M

Step 2: Calculate the concentration of OH⁻

We will use the ionic product of water expression.

[H⁺] [OH⁻] = 10⁻¹⁴

[OH⁻] = 10⁻¹⁴/[H⁺] = 10⁻¹⁴/3.981 × 10⁻¹³ = 0.02512 M

Step 3: Calculate the initial concentration of NaOH

NaOH is a strong base and the molar ratio of NaOH to OH⁻is 1:1. Thus, the initial concentration of NaOH is 1/1 × 0.02512 M = 0.02512 M.

Step 4: Calculate the moles of NaOH

We will use the definition of molarity.

M = moles of NaOH/liters of solution

moles of NaOH = M × liters of solution

moles of NaOH = 0.02512 mol/L × 0.5000 L = 0.01256 mol

Step 5: Calculate the mass of 0.01256 moles of NaOH

The molar mass of NaOH is 40.00 g/mol.

0.01256 mol × 40.00 g/mol = 0.5024 g


Related Questions

What is unit? Write down the units of mass, temperature and power​

Answers

Explanation:

a single thing, person, or group forming part of a whole There are 36 units in my apartment building. the least whole number : one. a fixed quantity (as of length, time, or value) used as a standard of measurement An inch is a unit of length.

mass=kilogram (kg)

temperature=kelvin

power=watt

hope it helps

stay safe healthy and happy..
A unit of measurement is a definite magnitude of a quantity, defined and adopted by convention or by law, that is used as a standard for measurement of the same kind of quantity. Any other quantity of that kind can be expressed as a multiple of the unit of measurement
Mass - kilogram ( kg )
Temperature - Kelvin
Power - watt

Predict the product when 2-methylbutanol is oxidised with pyridium chlorochromate in dichloromethane (PCC/CH2C12) a. CH3CH2CH(CH3)COOH b. CH3CH2CH2CH(CH3)CHO C. CH3CH2CH(CH3)CHO d. CH3CH2CH(CH3)OH 8:40 PM Type a message​

Answers

Answer:

c. CH3CH2CH(CH3)CHO

Explanation:

Hello there!

In this case, according to the process for the one-step oxidation of a primary alcohol with a moderately strong oxidizing agent like pyridinium chlorochromate (PCC), whereby an aldehyde is produced, we infer that the corresponding product will be 2-methylbutanal, which matches with the choice c. CH3CH2CH(CH3)CHO according to the following reaction:

[tex]CH_3CH_2CH(CH_3)CH_2OH\rightarrow CH_3CH_2CH(CH_3)COH[/tex]

Regards!

In some sheep, the presence of horns is produced by an autosomal allele that is dominant in males and recessive in females.A horned female is crossed with a hornless male. One of the resulting F1 females is crossed with a hornless male. What proportion of the male and female progeny from this cross will have horns?(5 marks)

Answers

Answer:

1/2 f1 will cross

Explanation:

answer it

What do phase diagrams demonstrate?

Select all that apply.

how the melting and boiling points of a substance change with pressure
how much heat will increase the temperature of a gram of a substance by 1°C
the pressure and temperature conditions in which a substance exists as a liquid, solid, or gas
a comparison of the temperature of a substance to the heat absorbed over time

Answers

Answer:

this answer is for first one

Explanation:

A higher evalations, where the atmospheric pressure is much lower, the boiling point increase with increased pressure up to the critical point where the gas and liquid properties become identical

g Calculate the number of grams of aluminum that is produced in 1.00 h by the electrolysis of molten AlCl3 if the electrical current is 10.0A.

Answers

Answer:

3.36 grams Al°(s)  

Explanation:

Given AlCl₃(s), determine the mass (grams) of Al°(s) produced from electrolysis of Aluminum Chloride at 10.0 amps for 1.00 hour.

AlCl₃(s) + 378.3°F (=192.4°C) => Al⁺³(l) + 3Cl⁻(l)

formula wt. Al° = 27g/mol

Faraday Constant (F°) = 96,500 amp·sec

? grams Al°(s) = 10.0amps x (1 mole e⁻/96,500amp-sec) x (1 mole Al°(s)/3 mole e⁻) x (27g Al°(s)/1 mole Al°(s)) x 3,600 sec = 3.36 grams Al°(s)

The 3.36 grams of aluminum are produced in 1 hour by the electrolysis of molten AlCl₃ when 10A current is passed.

What is electrolysis?

Electrolysis is a process that uses an electrical current to break chemical compounds. The electric current is passed through the substance to bring the chemical change by gain or loss of electrons.

The electrolysis of the aluminum chloride in the molten state is represented as:

AlCl₃  →   Al³⁺    +  3Cl⁻

At cathode:   Al³⁺  +  3e⁻  →  Al (s)

Given,  the current. I = 10 A and  t = 1 hr = 3600 s

We know that the current is calculated from the equation:  I = q/t

q = I× t

q = (10A) × (3600s)

q = 36 × 10³ C

We know, 96500 C of the charge has electrons = 1 mol

36 × 10³ C of the charge has electrons  = 0.373 mol

3 moles of electrons required to produce aluminum = 1 mol

0.373 mol of electrons will produce aluminum = 0.373/3 = 0.124 mol

We know that, the mass of one mole of Al = 27g

The mass of 0.124 mol of Al = 27 × 0.124 = 3.36 g

Therefore, the aluminum produced in 1 hour by the electrolysis of molten AlCl₃ is equal to 3.36 grams.

Learn more about electrolysis, here:

https://brainly.com/question/12054569

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54
Penny bought a club moss plant for her water garden. She needs to know how tall the plant will grow so she know
how much space it will need.
How tall will the plant likely grow?
O less than 5 centimeters because it is a seedless vascular plant
less than 5 centimeters because it is a nonvascular plant
O more than 5 centimeters because it is a seedless vascular plant
O more than 5 centimeters because it is a nonvascular plant

Answers

Answer:

less than 5 centimeters because it is a nonvascular plant

Explanation:

Mosses are a group of plants under the division Bryophyta. They are said to be the most primitive plant life in existence as they lack true roots, stems and leaves. They also lack vascular system, hence, they are regarded as non-vascular plants. They usually grow in very small sizes (about 0.2 - 10cm).

According to this question, Penny bought a club moss plant for her water garden and needs to know how tall the plant will grow so she know how much space it will need. Since it is a miss plant that lacks vascular tissues i.e. nonvascular, it will likely grow less than 5 centimeters in height.

Answer:

d

Explanation:

chemistry help!

This mysterious gas has a volume of 4.35 L and a pressure of 1.20 atm. If the pressure is changed to 0.95 atm, what will the new volume be? How do i set up this problem and solve it?

Answers

Refer to the attachment.

Hope this helps you...

Describe how you would prepare your assigned ester from a carboxylic acid and an alcohol. You do not need to include a detailed procedure, but you should include any necessary reagents or catalyst (solvents are not needed).

Answers

Answer:

The general preparation of esters( for example ethyl ethanoate) is through a process known as ESTERIFICATION.

Explanation:

The formation of an ester by the reaction between an alkanol and an acid is known as esterification. This reaction is extremely slow and reversible at room temperature, and is catalyzed by a high concentration of hydrogen ions.

In the preparation of one of the simpler esters known as ETHYL ETHANOATE the reactants include ethanol(an alcohol) and glacial ethanoic acid(a carboxylic acid) in the presence of concentrated tetraoxosulphate VI acid as a CATALYST. Note that, a catalyst is any substance that is able to increase the rate of a chemical reaction.

The mixture is warmed in a water bath( hot but not boiling) for about 25 minutes. The mixture is poured into a beaker partially filled with a sodium or calcium chloride to remove interacted ethanol. The ethyl ETHANOATE floats on the mixture as oily globules.

Which mechanisms is most significant in returning the ion concentrations to the resting state?

Answers

Answer:

Active transport by the Na+-K+ pump

Explanation:

Active transport by the Na+-K+ pump

Maintenance (and restoration) of the resting ion concentrations depends on the Na+-K+ pump. Once gated ion channels are closed, the combined action of the pump and ion leakage (particularly that of K+) establishes a resting membrane potential in a typical neuron of around âˆ'70 mV.

Explain why ionic compounds have higher boiling points than covalent compounds.​

Answers

Answer:

because the have stronger electrostatic force

How do forces between particles in gases compare to forces in the other states of matter?​

Answers

The forces in gases are weaker than forces in solids and liquids.

Because they have more kinetic energy that overcomes the force of attraction.

A cylinder contains 3.1 L of oxygen at 300 K and 2.7 atm. The gas is heated, causing a piston in the cylinder to move outward. The heating causes the temperature to rise to 610 K and the volume of the cylinder to increase to 9.4 L.
How many moles of gas are in the cylinder?
Express your answer using two significant figures.

Answers

Answer: The moles of gas present in the cylinder is 0.34 moles.

Explanation:

Given: [tex]P_{1}[/tex] = 2.7 atm,   [tex]V_{1}[/tex] = 3.1 L,     [tex]T_{1}[/tex] = 300 K

[tex]P_{2}[/tex] = ?,      [tex]V_{2}[/tex] = 9.4 L,       [tex]T_{2}[/tex] = 610 K

Formula used to calculate the final temperature is as follows.

[tex]\frac{P_{1}V_{1}}{T_{1}} = \frac{P_{2}V_{2}}{T_{2}}[/tex]

Substitute the values into above formula as follows.

[tex]\frac{P_{1}V_{1}}{T_{1}} = \frac{P_{2}V_{2}}{T_{2}}\\\frac{2.7 atm \times 3.1 L}{300 K} = \frac{P_{2} \times 9.4 L}{610 K}\\P_{2} = \frac{5105.7}{2820} atm\\= 1.81 atm[/tex]

Now, moles present upon heating the cylinder are as follows.

[tex]P_{2}V_{2} = n_{2}RT_{2}\\1.81 atm \times 9.4 L = n_{2} \times 0.0821 L atm/mol K \times 610 K\\n_{2} = \frac{17.014}{50.081} mol\\= 0.34 mol[/tex]

Thus, we can conclude that moles of gas present in the cylinder is 0.34 moles.

Which of the five type of equilibrium problems best applies to this question: Consider the following reaction at equilibrium. What effect will reducing the volume of the reaction mixture have on the system

Answers

Answer:

d

Explanation:

By how many times would you expect Al2(SO4)3 to depress the F.P of water compared to sucrose C12H22011 ?​

Answers

Answer:

By how many times would you expect Al2(SO4)3 to depress the F.P of water compared to sucrose C12H22011 ?.

Explanation:

The freezing point of a pure solvent decreases further by adding a nonvolatile solute.

This is called depression in freezing point.

When an ionic solute is dissolved then the depression in the freezing point is proportional to the number of ions present in the solution.

In aluminum sulfate, there are five ions formed as shown below:

[tex]Al_2(SO_4)_3(aq)->2Al^3^+(aq)+3SO_4^2^-(aq)[/tex]

But sucrose is a covalent compound and it does not undergo dissociation.

Hence, aluminum sulfate decreases the freezing point of water by five times compared to sucrose.

Explanation:

The speed of sound depends on the __?_____ and ____?____ of the medium through which it travels

Answers

Answer:

Density and rigidity

following this list of common polyatomic ions what would be the charge for aluminum nitrate?
Nitrate NO3
Phosphate PO43,
Sulfate SO4 -2
acetate C2H3O2-1
Ammonium NH4.
Chromate CrO4-2
Carbonate C03-2
Dichromate CrO7-2
Permanganate MnO4-1
What would be the correct answer for Aluminum nitrate

Answers

Answer:

Nitrate NO3

here's your answer, hope it helps you

What molecule is this

Answers

Answer:

That is a " ball and stick " model which represents carbon compounds.

Explanation:

This is the answer. Hope it helps you find what you're looking for.

Will give brainliest answer please give explanation


33.5 cs=_________s

Answers

Answer: 3.4 × 10 -1 equal 33.5 cs. May I have brainiest? pls. (the -1 is to the power of the ten.

What type of a liquid will have a pH value equal to 12? (1 point)
Basic
Neutral
Strong acid
Weak aci

Answers

Answer: it will be basic

pH that ranges from 0-6 are acid

pH of EXACTLY 7 is neutral

pH greater than 7 are strongly basic or base

It will be Basic

Explanation:

Anything with a pH lower then 7 is acidic, anything higher then 7 is basic, and exactly 7 is neutral. Something with a pH of 12 would be considered basic and would a a strength comparable to bleach. Below I’ve attached a chart that should help also! Learning about the pH scale can be tricky and I recommend using charts to help memorize it.

I hope this helps you! Please consider marking me the Brainliest, it’s not necessary but very much appreciated. Stay healthy and stay safe! :)

How many doubtful digit(s) is/are allowed in any measured quantity?
(Only 3 choices.)
A.) 1
B.) 2
C.) zero​

Answers

Answer:

zero

Explanation:

I I think one should be so accurate with measurements and experiments

An unknown weak acid with a concentration of 0.530 M has a pH of 5.600. What is the Ka of the weak acid

Answers

Answer:

Ka = 3.45x10⁻⁶

Explanation:

First we calculate [H⁺], using the given pH:

pH = -log[H⁺][H⁺] = [tex]10^{-pH}=10^{-5.6}[/tex] [H⁺] = 2.51x10⁻⁶ M

To solve this problem we can use the following formula describing a monoprotic weak acid:

[H⁺] = [tex]\sqrt{C*Ka}[/tex]

We input the data that we already know:

2.51x10⁻⁶ = [tex]\sqrt{0.530*Ka}[/tex]

And solve for Ka:

Ka = 3.45x10⁻⁶

What are the concentrations of hydronium and hydroxide ions in a solution with pH 2.6?

Please help omg. Ive been stuck for 15 minutes​

Answers

Answer:

The concentrations of hydronium and hydroxide ions in a solution with pH 2.6 are 2.51*10⁻³ and 3.98*10⁻¹² respectively.

Explanation:

pH is a measure of the acidity or alkalinity of an aqueous solution. The pH indicates the concentration of hydrogen ions present in certain solutions. Mathematically it is defined as the opposite of the base 10 logarithm or the negative logarithm of the activity of hydrogen ions, whose equation is

pH= -log [H⁺]

So, being pH= 2.6 and replacing in the definition of pH:

2.6= -log [H⁺]

[tex][H^{+} ]=10^{-2.6}[/tex]

[H⁺]=2.51*10⁻³

pOH is a measure of the concentration of hydroxide ions (OH⁻). The sum between the pOH and the pH results in 14:

pOH + pH= 14

So, being pH= 2.6:

pOH + 2.6= 14

pOH= 14 - 2.6

pOH= 11.4

The pOH is defined as the negative logarithm of the activity of the hydroxide ions. That is, the concentration of OH⁻ ions:

pOH= - log [OH⁻]

Being pOH= 11.4 and replacing

11.4= -log [OH⁻]

[tex][OH^{-} ]=10^{-11.4}[/tex]

[OH⁻]= 3.98*10⁻¹²

The concentrations of hydronium and hydroxide ions in a solution with pH 2.6 are 2.51*10⁻³ and 3.98*10⁻¹² respectively.

Cal is titrating 57.7 mL of 0.311 M HBr with 0.304 M Ba(OH)2. How many mL of Ba(OH)2 does Cal need to add to reach the equivalence point?

Answers

Answer:

118.06 mL

Explanation:

The neutralization reaction between HBr (acid) and Ba(OH)₂ (base) is the following:

2HBr + Ba(OH)₂ → BaBr₂ + 2H₂O

According to the equation, 2 moles of HBr react with 1 mol Ba(OH)₂. Thus, at the equivalence point the moles of acid and base react completely:

2 moles HBr = 1 mol Ba(OH)₂

We can replace the moles by the product of the molar concentration (M) and volume (V):

2 x (M HBr) x (V HBr) = M Ba(OH)₂ x V Ba(OH)₂

Now, we introduce the data in the equation to calculate the volume in mL of Ba(OH)₂:

V Ba(OH)₂ = (2 x (M HBr) x (V HBr))/M Ba(OH)₂

                 = (2 x 0.311 M x 57.7 mL)/(0.304 M)

                 = 118.06 mL

Therefore, 118 mL of Ba(OH)₂ are needed.

Imagine you are celebrating a birthday in December and need balloons. The temperature in the
store where you are purchasing the balloons is approximately 25°C and each balloon is filled
to a volume of 2 liters to obtain maximum pressure.
Use the gas laws to explain what will happen to the volume and pressure of the gas in the
balloon when go outside, where the temperature is 0°C. Include both Charles's Law
and Gay-
Lussac's Law in your answer.
ILL GIVE BRAINIEST PLEASE HELP

Answers

So I think that this is very cool elsewhere think that it’s also a little bit cool so you’re selling birthday OK the pressure is definitely 25 and the 2 L so basically the answer is five so everything is great that’s the answer

A 1.19 g sample of an unknown halogen occupies 109 mL at 398 K and 1.41 atm. What is the identity of the halogen

Answers

Answer:

The halogen is Iodine.

Explanation:

Using the ideal gas equation, we find the number of moles of gas present, n.

PV = nRT where P = pressure of gas = 1.41 atm, V = volume of gas = 109 mL = 0.109 L, n = number of moles of gas, R = molar gas constant = 0.082 L-atm/mol-K and T = temperature of gas = 398 K

Since PV = nRT, making n subject of the formula, we have

n = PV/RT

substituting the values of the variables into the equation, we have

n = 1.41 atm × 0.109 L/(0.082 L-atm/mol-K × 398 K)

n = 0.15369 atm-L/32.636 L-atm/mol

n = 0.0047 mol

Since n = m/M where m = mass of gas = 1.19 g and M = relative molecular mass of gas

So, M = m/n

M = 1.19 g/0.0047 mol

M = 252.7 g

Since halogens are diatomic the relative atomic mass is M/2 = 252.7g/2 = 126.34 g

From tables, the only halogen with this atomic mass is Iodine.

So, the halogen is Iodine.

A beaker is filled to the 500 mL mark with alcohol. What increase in volume (in mL) does the beaker contain when the temperature changes from 5° C to 30° C? (Neglect the expansion of the beaker, evaporation of alcohol and absorption of water vapor by alcohol.) The volume coefficient of expansion γγ for alcohol = 1.12 x 10-4 K-1

Answers

Answer:

"1.4 mL" is the appropriate solution.

Explanation:

According to the question,

[tex]v_0=500[/tex][tex]\alpha =1.12\times 10^{-4}[/tex][tex]\Delta \epsilon = 25[/tex]

Now,

Increase in volume will be:

⇒ [tex]\Delta V = \alpha\times v_0\times \Delta \epsilon[/tex]

By putting the given values, we get

           [tex]=1.12\times 10^{-4}\times 500\times 25[/tex]

           [tex]=1.12\times 10^{-4}\times 12500[/tex]

           [tex]=1.4 \ mL[/tex]

I need help with the practice question at the bottom. Thank you.

Answers

Explanation:

For this question, we apply the equation: Q = mCp AT Where m is the mass of the substance, Cp

is its specific heat capacity and AT is the

temperature change. Q = 896 x 0.45 x (5-94)

Q = -35884.8 Joules

So about -36 kilojoules of heat is released.

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An object was measured by a worker as 14.6cm long, however, the manufacturer specifications list the length of the object at 14.4cm. What is the percent error in the worker's measurement? A. 1.39%
B. 1.37%​

Answers

it's 0.2cm different from the expected value, wich was 14.6cm

how many percent that are is calculated in the screenshot.

rounded it's 1.37%

How long must a 40.0 amp current flow through a solution of iron(III) chloride in order to produce 5.00 moles of iron?

Answers

Answer:

10.1 h

Explanation:

Let's consider the reduction half-reaction of iron from an aqueous solution of iron (III) chloride.

Fe³⁺(aq) + 3 e⁻ ⇒ Fe(s)

We can calculate the time required to produce 5.00 moles of Fe using the following relationships.

1 mole of Fe is produced when 3 moles of electrons circulate.1 mole of electrons has a charge of 96486 C (Faraday's constant).1 A = 1 C/s.1 h = 3600 s.

[tex]5.00molFe \times \frac{3 mole^{-} }{1molFe} \times\frac{96486C}{1mole^{-} } \times \frac{1s}{40.0C} \times \frac{1h}{3600s} = 10.1 h[/tex]

In water, Vanillin, C8H8O3, has a solubility of 0.070 moles of vanillin per liter of solution at 25C. What will be produced if 5.00 g of vanillin are added to 1 L of water at 25 C?

Answers

Answer:

The full amount (5.00 g) will be dissolved in 1 L of water at 25°C.

Explanation:

The molecular weight (MW) of Vanillin (C₈H₈O₃) is calculated from the chemical formula as follows:

MW(C₈H₈O₃) = (12 g/mol x 8) + (1 g/mol x 8) + (16 g/mol x 3) = 152 g/mol

If 0.070 mol of C₈H₈O₃ are soluble per liter of water at 25°C, the maximum mass that can be dissolved in 1 L is:

0.070 mol x 152 g/mol = 10.64 g

Since 5.00 g is lesser than the maximum amount that can be dissolved (10.64 g), the added amount will be completely dissolved in 1 L of water at 25°C.

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