What is the [OH-] of a solution with a pH of 3.89?

Which one is it?
7.76 x 10^-11

1.29 x 10^-4

2.11 x 10^-6

4.51 x 10^-10

Answer:

B. strong base titration with a strong acid

Answer:

Our bodies convert chemical energy in our food into mechanical energy for us to move.

An electric fan transforms electrical energy into kinetic energy

Reword it tho

Hope this helps!!

Answer:

Your answer is C

Explanation:

When an acid and base react, the acidic hydrogen ion and the basic hydroxide ion in each acid and base neutralize each other and form water. Meanwhile the conjugate base and conjugate acid (the leftover compounds) react to form an ionic molecule, or a salt. (In chemistry, when an anion and a cation form an ionic bond the new molecule is called a salt). Hope this helps!

Answer: A.) 2 is the answer.

Explanation:

Answer:

2-pentene

Explanation:

The name of the alkene is 2 pentene. The correct option is B, 2-pentene.

Alkenes with the chemical formula [tex]C_5H_10[/tex] are known as pentene. Within its molecular structure, each has one double bond.

The given alkene [tex]CH_3CH = CHCH_2CH_3[/tex] is 2-pentene because the double bond is present in the second carbon and it's pentene because there are five carbons present.

Thus, the correct option is B. 2-pentene.

Learn more about 2-pentene

https://brainly.com/question/19593832

#SPJ2

The change in free energy can help us to discover whether a reaction can be sponteanous or not. The change in free energy fro this reaction is -1.51 kJ/mol.

The change in free energy is referred to as that which determines the spontenity of a chemical reaction. For a spontenous reaction the change in free energy must be negative.

Now;

ΔG = -RTlnK

R = gas constant

T = temperature

K = equilibrium constant

So;

ΔG = -(8.314 * 298 * ln 436)

ΔG = -1.51 kJ/mol

Learn more about free energy: https://brainly.com/question/15319033

Three solutions are mixed together to form a single solution. The precipitate in the solution is PbS and PbCl₂.

Precipitates are the residues that are present in the solution. These residues are solid that came out of the solution.

Here given 3 compounds are water-soluble.

From the solution, we have to find the possible combination which is water-soluble.

Consider,

Pb(CH3COO)₂ Pb₂+(aq) + 2CH₃COO-(aq)

Na₂S₂Na+(aq) + S₂-(aq)

LiCl Li+(aq) + Cl-(aq)

Now consider a potential accumulation of positive and negative ions which is water-soluble.

The possible accumulations are,

PbS , PbCl₂

Ca(CH₃COO)₂ , CaS

Now viewing with solubility charge, we can find that both PbS and PbCl2 are water indissoluble and create a precipitate.

But both Ca(CH₃COO)₂ and CaS are water-soluble.

Therefore, the precipitates are PbS and PbCl₂.

To learn more about precipitates, refer to the link:

https://brainly.com/question/20925010

#SPJ2

Answer:

[tex]819 \: g = 819 \times {10}^{ - 3} \: kg = 0.819 \: kg \\ 0.819 \: kg - 0.497 \: kg \\ = 0.322 \: kg[/tex]

Answer:

0.004235 M

Explanation:

The neutralization reaction of this question is given as follows:

Mg(OH)2 + 2HCl → MgCl2 + 2H2O

Using the formula below:

CaVa/CbVb = na/nb

Where;

Ca = concentration of acid (M)

Cb = concentration of base (M)

Va = volume of acid (mL)

Vb = volume of base (mL)

na = number of moles of acid = 2

nb = number of moles of base = 1

From the information provided in this question;

Ca = ?

Cb = 0.00125 M

Va = 425 mL

Vb = 720 mL

na (HCl) = 2

nb = (Mg(OH)2) = 1

Using the formula; CaVa/CbVb = na/nb

Ca × 425/0.00125 × 720 = 2/1

425Ca/0.9 = 2

472.2Ca = 2

Ca = 2/472.2

Ca = 0.004235 M

Answer:

The answers to your questions are given below.

Explanation:

1. The symbol of Zinc is Zn

2. Determination of the proton number

Atomic number is simply defined as the number of protons in the nucleus of an atom. Mathematically, it is expressed:

Atomic number = proton number

Atomic number = 30

Therefore,

Proton number = 30

3. Determination of the neutron number

Mass Number = 65

Proton number = 30

Neutron number =?

Mass number = Proton + Neutron

65 = 30 + Neutron

Collect like terms

65 – 30 = Neutron

35 = Neutron

Thus,

Neutron number = 35

4. Determination of the electron number

Since the element is in it's ground state (i.e it has no charge), thus, the number of protons of the element is the same as number of electrons i.e

Electron number = proton number

Proton number = 30

Thus,

Electron number = 30

Answer:

The thermal efficiency of an engine is [tex]0.15[/tex] that is 15%

Explanation:

Specific heat of a gas at constant volume is

[tex]C_{v}=\frac{fR}{2}[/tex]

here, [tex]f=[/tex]degree of freedom

[tex]R=[/tex]universal gas constant

Thermal efficiency of a cycle is

[tex]\frac{total workdone}{gross heat absorbed}[/tex]

Gross heat absorbed is amount of heat that absorbed.

ω[tex]=P_{o} V_{o}[/tex]

[tex]Q_{AB}=[/tex]Δ[tex]V_{AB}+[/tex]ω[tex]_{AB}[/tex][tex]=nC_{v}(T_{f}-T_{i} )[/tex]

       [tex]=n\frac{f}{2}(RT_{f}-RT_{i} )[/tex][tex]=\frac{f}{2}(P_{o}V_{o} )[/tex]

[tex]Q_{BC}=n(\frac{f}{2}+1 )R(T_{f}-T_{i} )[/tex]

       [tex]=(\frac{f}{2} +1)(4P_{o}V_{o}-2P_{o}V_{o} )[/tex]=[tex]=(\frac{f}{2}+1)2P_{o}V_{o}[/tex]

[tex]Q_{CD}=-ve and Q_{DA}=-ve[/tex]    these 2 are not the part of gross heat

η[tex]=\frac{P_{o}V_{o} }{(\frac{3f}{2}+2 )(P_{o}V_{o})}[/tex]

  [tex]=\frac{1}{(\frac{3f}{2}+2 )}[/tex]

For monoatomic gas [tex]f=3[/tex]

η[tex]=\frac{2}{13}[/tex]

  [tex]=0.15[/tex]

Answer:

3) Q = -836.8 J.

4) Q = 950J.

Explanation:

Hello there!

In this case, for those calorimetry problems, we use the general equation:

[tex]Q=mC\Delta T[/tex]

Thus, we proceed as follows:

3) Here, the temperature difference is from 80 °C to 40 °C, the mass is 5.0 g and the specific heat 4.184 in SI units; thus, the heat is calculated as follows:

[tex]Q=(5g)(4.184\frac{J}{g\°C} )(40\°C-80\°C)\\\\Q=-836.8J[/tex]

4) Here, the temperature difference is from 100 °C to 200 °C, the mass is 5.0 g and the specific heat about 1.90 in SI units; thus, the heat is calculated as follows:

[tex]Q=(5g)(1.90\frac{J}{g\°C} )(200\°C-100\°C)\\\\Q=950J[/tex]

Regards!

Answer:

The cell wall surrounds the plasma membrane and provides the cell tensile strength and protection. ... The cell wall surrounds the plasma membrane of plant cells and provides tensile strength and protection against mechanical and osmotic stress.

hope It Helps U

Please Mark me As brainlist

Answer: D

Explanation:

liquid evaporates faster at higher temperatures because more particles have a higher speed and can overcome attractions in the liquid.

Answer:

D. A liquid evaporates faster at higher temperatures because more particles have a higher speed and can overcome attractions in the liquid.

Explanation:

Correct on Edge 2022!!!

Good luck everyone, you got this! Have a great day!

Answer:

Ca - 66%, P - 34%

Explanation:

So, this is the formula we can use to find the amount of each element:

Element count * Atomic mass = Mass

Plug in our elements for this:

Ca - 3*40.078=120.234

P - 2*30.973=61.946

Now, to find the percentage of mass, we must find total mass, and divide the two elements mass count by this total mass:

120.234+61.946=182.18

Now divide each element mass by the total mass:

Ca - 120.234/182.18=0.6599(Round to 0.65)

P - 61.946/182.18=0.34002(Round to 0.34)

Then multiply both numbers by 100 to get the percentage:

Ca - 65%

P - 34%

So these our your two answer!

Hope this helps!

Answer:

643g of methane will there be in the room

Explanation:

To solve this question we must, as first, find the volume of methane after 1h = 3600s. With the volume we can find the moles of methane using PV = nRT -Assuming STP-. With the moles and the molar mass of methane (16g/mol) we can find the mass of methane gas after 1 hour as follows:

Volume Methane:

3600s * (0.25L / s) = 900L Methane

Moles methane:

PV = nRT; PV / RT = n

Where P = 1atm at STP, V is volume = 900L; R is gas constant = 0.082atmL/molK; T is absolute temperature = 273.15K at sTP

Replacing:

PV / RT = n

1atm*900L / 0.082atmL/molK*273.15 = n

n = 40.18mol methane

Mass methane:

40.18 moles * (16g/mol) =

Answer:

C

Explanation:

Kepler first law means that planets mover around the sun in a elliptical motion

Answer: First box----Hail

             Second Box-------Snow

             Thrid Box-------Sleet

              Forth Box-----Rain

Hope that helped! :)

I believe that this statement is true

Answer:

0.921 moles

Explanation:

1.91 M means 1.91 moles/liter

482 mL = 0.482 L

0.482 L × 1.91 moles/liter = 0.92062 moles

Answer:

0.766atm

Explanation:

Boyles law

P1V1=P2V2

1×635=P2×829

P2=635/829

P2=0.766atm

Answer:

436.8 mmHg.

Explanation:

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

Total pressure (Pₜ) = 0.93 atm

Pressure of N₂ (Pₙ₂) = 270 mmHg

Pressure of O₂ (Pₒ₂) =?

Next, we shall convert the total pressure to mmHg . This can be obtained as follow:

1 atm = 760 mmHg

Therefore,

0.93 atm = 0.93 × 760 mmHg / 1 atm

0.93 atm = 706.8 mmHg

Finally, we shall determine the pressure of the O₂. This can be obtained as follow:

Total pressure (Pₜ) = 706.8 mmHg

Pressure of N₂ (Pₙ₂) = 270 mmHg

Pressure of O₂ (Pₒ₂) =?

Pₜ = Pₙ₂ + Pₒ₂

706.8 = 270 + Pₒ₂

Collect like terms

706.8 – 270 = Pₒ₂

436.8 = Pₒ₂

Pₒ₂ = 436.8 mmHg

Thus, the pressure of O₂ is 436.8 mmHg

Answer:

The answer is "Tetrahedral".

Explanation:

The carbon atom of approximately [tex]109.5^{\circ}[/tex] with four attachments. Its general form is one of a tetrahedron: a polyhedron consisting of 4 triangular sides, six straight edges, and four vertex corners from all faces equilateral triangles. The triangular pyramid is often referred to as the triangular pyramid.

Answer:

well please answer me it's question too after you get it

Explanation:

i am also stucked in that question

No. of molecules of any substance is one mole

= Avogadro's Number = (6.022 x 10^23)

So, no. of molecules in 7.2 moles of sodium fluoride

= 7.2 × (6.022 x 10^23)

= 4.33584^24

Answer:

[tex]T_2=894.45K=621.30\°C[/tex]

Explanation:

Hell there!

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

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

Thus, we solve for the final temperature, T2, as shown below (make sure T1 is in Kelvins):

[tex]T_2=\frac{V_2T_1}{V_1} \\\\T_2=\frac{(25+273.15)K*45L}{15L}\\\\T_2=894.45K=621.30\°C[/tex]

Regards!

Explanation:

M(Bapo3) = 216m/mol

n = 3.8 mole

m = M × n = 216 × 3.8 = 820.8g

Answer:

false im pretty sure.