which of the following is an acid?

HF
KOH
LIF
NH3

Answer:

2 Na(s) + C(s) + 3/2 O₂(g) → Na₂CO₃(s)

Explanation:

The molar enthalpy of formation of a chemical is defined as the change in enthalpy during the formation of 1 mole of the substance from its constituent elements (Constituent elements are pure elements you have in the periodic table)

For Na₂CO₃ constituent elements are Na(s), C(s) and O₂(g) and the chemical equation that represents the molar enthalpy is:

Answer:

As you know, one mole of any substance contains exactly

6.022

⋅

10

23

molecules of that substance - this is known as Avogadro's number.

Notice that you're dealing with more than

6.022

⋅

10

23

molecules of carbon dioxide, which means that you'll also be dealing with more than one mole of the compound.

More specifically, you'll have

1.5

⋅

10

26

molecules

⋅

1 mole CO

2

6.022

⋅

10

23

molecules

=

2.491

⋅

10

2

moles CO

2

Now, a substance's molar mass tells what the mass of one mole of that substance is. In carbon dioxide's case, its molar mass is equal to

44.01 g/mol

, which means that every mole of

CO

2

will have a mass of

44.01 g

.

In your case,

2.491

⋅

10

2

moles of

CO

2

would have a mass of

2.491

⋅

10

2

moles CO

2

⋅

44.01 g

1

mole CO

2

=

109.63 g

Rounded to two sig figs, the number of sig figs you have for the number of molecules of

CO

2

, the answer will be

m

C

O

2

=

110 g

1) Based on the crystal field strength, Cl ligand would give the longest d-d transition when complexed with Ti(III). as this is the weak field igand and would cause minimum splitting of d orbitals.

Answer:

option a

Explanation:

pls mark me as brainliest

Answer:

461.85 degrees Celsius

Answer:

The concentration in mol/L =  4.342 mol/L

Explanation:

Given that :

mass of sodium chloride = 25.4 grams

Volume of the volumetric flask = 100 mL

We all know that the molar mass of sodium chloride NaCl = 58.5 g/mol

and number of moles = mass/molar mass

The number of moles of sodium chloride = 25.4 g/58.5 g/mol

The number of moles of sodium chloride = 0.434188 mol

The concentration in mol/L = number of mol/ volume of the solution

The concentration in mol/L = 0.434188 mol/ 100 × 10⁻³ L

The concentration in mol/L =  4.34188 mol/L

The concentration in mol/L =  4.342 mol/L

Answer:

Explanation:

Sr(OH)2 (aq) ⇔ Sr+2 (aq) + 2OH- (aq)

Answer:

5000g

Explanation:

mass= density × volume

Since the unit of density here is g/mL, we need to convert the volume to mL.

1L= 1000mL

4L= 4 ×1000 = 4000 mL

Mass of object

= 1.25 ×4000

= 5000g

Answer:

5,000 grams

Explanation:

The mass of an object can be found by multiplying the volume by the density.

mass= volume * density

The density is 1.25 g/mL and the volume is 4 L.

First, we must convert the volume to mL. The density is given in grams per milliliter, but the volume is given in liters.

There are 1,000 mL per L. The volume is 4 L. Therefore, we can multiply 4 and 1,000.

4 * 1,000 = 4,000

The volume is 4,000 mL.

Now, find the mass of the object.

mass= volume * density

volume = 4,000

density= 1.25

mass= 4,000 * 1.25 = 5,000

Add the appropriate units for mass, in this case, grams, or g.

mass= 5,000 g

The mass of the object is 5,000 grams.

Answer:

CH2Cl2 is polar

Explanation:



Answer:

vinegr and soda ..................

........

Answer:

acid + base = salt

so the answer is vinegar and soda

Explanation:

hope it helps you

Mark my answer as brainlist

have a good day

Plants play a vital role in the environment because photosynthesis uses atmospheric carbon dioxide and water to produce sugars and oxygen. Option C is correct.

Photosynthesis is the process by which plants, algae, and some bacteria convert light energy into chemical energy in the form of glucose (sugar). This process occurs in the chloroplasts of plant cells and requires the presence of sunlight, carbon dioxide (CO₂), and water (H₂O).

During photosynthesis, plants absorb carbon dioxide from the atmosphere through tiny openings called stomata in their leaves. At the same time, they take in water from the soil through their roots. Through a series of complex chemical reactions, the energy from sunlight is used to combine carbon dioxide and water, resulting in the production of glucose (sugar) and the release of oxygen (O₂) as a byproduct.

This process is represented by the equation:

6CO₂ + 6H₂O + sunlight → C₆H₁₂O₆ (glucose) + 6O₂

Plants use the glucose produced through photosynthesis as a source of energy for various metabolic processes and growth. The released oxygen is essential for the survival of other organisms, including humans, as it is used in cellular respiration to release energy from glucose.

Hence, C. is the correct option.

To know more about chemical energy here

https://brainly.com/question/1371184

#SPJ2

Answer:

a. Moles in the vessel = 1.85 moles of the gas

b. 1.11x10²⁴ molecules are in the vessel

Explanation:

a.It is possible to determine moles of a gas using the general law of gases:

PV = nRT

Where P is pressure: 5.00atm; V is volume = 9.00L; R is gas constant: 0.082atmL/molK; T is absolute temperature: 273.15K +24.0 = 297.15K

Computing the values:

PV / RT = n

5.00atm* 9.00L / 0.082atmL/molK*297.15K = n

b. With Avogadro's number we can convert moles of any compound to molecules thus:

Avogadro's number = 6.022x10²³ molecules / mole

1.85moles ₓ (6.022x10²³ molecules / mole) =

Answer:

[tex][F^-]_{max}=4x10{-3}\frac{molF^-}{L}[/tex]

Explanation:

Hello,

In this case, for the described situation, we infer that calcium reacts with fluoride ions to yield insoluble calcium fluoride as shown below:

[tex]Ca^{+2}(aq)+2F^-(aq)\rightleftharpoons CaF_2(s)[/tex]

Which is typically an equilibrium reaction, since calcium fluoride is able to come back to the ions. In such a way, since the maximum amount is computed via stoichiometry, we can see a 1:2 mole ratio between the ions, therefore, the required maximum amount of fluoride ions in the "hard" water (assuming no other ions) turns out:

[tex][F^-]_{max}=2.0x10^{-3}\frac{molCa^{2+}}{L}*\frac{2molF^-}{1molCa^{2+}} \\[/tex]

[tex][F^-]_{max}=4x10{-3}\frac{molF^-}{L}[/tex]

Best regards.

Answer:

B. Bohr’s model electrons cannot exist between orbits, but in the electron cloud model, the location of the electrons cannot be predicted.

AND

C. The modern model explains all available data about atoms; Bohr’s model does not.

Explanation:

The answers are right on Edge. :)

Answer:

b and c

Explanation:

my assignment was 100% 2022

Answer:

natural mineral water.

Answer:

A precipitate will form, AgI

Explanation:

When Ag⁺ and I⁻ ions are in an aqueous media, AgI(s), a precipitate, is produced or not based on its Ksp expression:

Ksp = 8.3x10⁻¹⁷ = [Ag⁺] [I⁻]

Where the concentrations of the ions are the concentrations in equilibrium

For actual concentrations of a solution, you can define Q, reaction quotient, as:

Q = [Ag⁺] [I⁻]

If Q > Ksp, the ions will react producing BaCO₃, if not, no precipitate will form.

Actual concentrations of Ag⁺ and I⁻ are:

[Ag⁺] = [AgNO₃] = 2.0x10⁻⁵ × (300mL / 500.0mL) = 1.2x10⁻⁵M

[I⁻] = [NaI] = 2.5x10⁻⁹ × (200mL / 500.0mL) = 1.0x10⁻⁹M

500.0mL is the volume of the mixture of the solutions

Replacing in Q expression:

Q = [Ag⁺] [I⁻]

Q = [1.2x10⁻⁵M] [1.0x10⁻⁹M]

Q = 1.2x10⁻¹⁴

As Q > Ksp

Answer:

ΔH∘rxn of the reaction is -521.6kJ

Explanation:

Complete question: "Calculate the value of ΔH°rxn for 2F2(g)+2H2O(l)⟶4HF(g)+O2(g)"

You can find the ΔH of a reaction by the algebraic sum of similar reactions (Hess's law) as follows:

(1) H₂(g) + F₂(g) ⟶ 2HF(g) ΔH∘rxn=−546.6 kJ

(2) 2H₂(g)+O₂(g)⟶2H₂O(l) ΔH∘rxn=−571.6 kJ

Subtracting 2ₓ(1) - (2)

2ₓ(1) 2H₂(g) + 2F₂(g) ⟶ 4HF(g) ΔH∘rxn=2ₓ−546.6 kJ = -1093.2kJ

-(2) 2H₂O(l) ⟶ 2H₂(g)+O₂(g) ΔH∘rxn=- (-571.6 kJ) = 571.6kJ

2ₓ(1) - (2) 2F₂(g)+ 2H₂O(l) ⟶ 4HF(g) + O₂(g)

H₂(g) are cancelled because are the same in products and reactants

ΔH∘rxn = -1093.2kJ + 571.6kJ

ΔH∘rxn = -521.6

Answer:

  30. 5 planes are shown

  31. 1 plane

  32. CEF

  33. on line AB

  34. E or F

   35. ABCD or BCEF or CDEF or ACEF

Explanation:

30. Each of the surfaces of the rectangular pyramid is a plane. There are 5 planes.

__

31. 3 points define one plane only.

__

32. The only points shown on the same line segment are points E, F, and C.

__

33. If G is to be collinear with A and B, it must lie on line AB.

__

34. The only points shown that are not on plane N are points E and F. Either of those will do.

__

35. There are three planes that have 4 points shown on them. The four points that are on the same plane are any of ...

Plane ACEF is not shown on the diagram, but we know that those 4 points are also coplanar. (Any point not on line CE, together with the three points on that line, will define a plane with 4 coplanar points.)

Answer:

See explanation

Explanation:

When we talk about electrophilic substitution, we are talking about a substitution reaction in which the attacking agent is an electrophile. The electrophile attacks an electron rich area of a compound during the reaction.

The five membered furan ring is aromatic just as benzene. This aromatic structure is maintained during electrophilic substitution reaction. The attack of the electrophile generates a resonance stabilized intermediate whose canonical structures have been shown in the image attached.

Answer:

Explanation:

Before proceeding to answering the questions, let's try and understand each term.

Gravitational energy can be defined as the potential energy an object has when placed in a high position (compared to been placed in a low position). Examples include; a knife been placed at the top of the cupboard, a ball at the top of a hill.

Nuclear energy can be defined as the energy released or consumed as a result of splitting or joining together of the nuclei (plural of nucleus) of atom(s). The process of splitting an atomic nucleus is called nuclear fission while the process of joining two nuclei of atoms is called nuclear fusion.

Radiant energy can be defined as the energy of electromagnetic wave. One of the properties of electromagnetic waves is that they travel through space. Examples include X-rays and light

Stored mechanical energy can be defined as the potential energy an object has as a result of the application of force. Examples include; a stretched rubber band, a compressed spring

To convert from mass concentration to molar concentration we use the formula;

Mass concentration = molar concentration * molar mass

Molar concentration of Na2SO4 = 0.700 M

Molar mass of Na2SO4  = 2(23) + 32 + 4(16) = 142 gmol-1

Hence;

Mass concentration = 0.700 M * 142 gmol-1

Mass concentration = 99.4 g/mol

To know more about concentration, see

https://brainly.com/question/23437000

Answer:

Most of our coins are metal sandwiches. The outside layers are three-quarters copper and one-quarter nickel, and the "filling" is solid copper. Pennies are made of zinc coated with copper. Only nickels are one solid material—that same 75% copper/25% nickel alloy

Explanation:

Answer:

We can have: Calcium, strontium, or barium

Explanation:

In this case, we have to remember the solubility rules for sulfate [tex]SO_4~^-^2[/tex] and the chloride [tex]Cl^-[/tex]:

Sulfate

All sulfate salts are SOLUBLE-EXCEPT those also containing: Calcium, silver, mercury (I), strontium, barium or lead.([tex]Ca^+^2~,Ag^+~,Hg_2^+^2~,Sr^+2~,Ba^+^2~,Pb^+^2[/tex]), which are NOT soluble.

Chloride

All chloride salts as SOLUBLE-EXCEPT those also containing: lead, silver, or mercury (I). ([tex]Pb^+^2~,Ag^+~,Hg_2~^+^2[/tex]), which are NOT soluble.

If we the salt formed a precipitated with the sulfate anion, we will have as possibilities "Calcium, silver, mercury (I), strontium, barium or lead". If We dont have any precipitated with the Chloride anion we can discard "Silver, mercury (I),  lead" and our possibilities are:

"Calcium, strontium, or barium".

I hope it helps!

Answer:

1.543 pounds = 700 grams

Answer:

15. Critical angle of glass and water combination, θ = 62.45°

16. Critical angle for the interface between Mystery A and glass, θ = 37.93°

Note; The question is incomplete. The complete question is as follows:

Medium Air Water Glass Mystery A Mystery B Table-2 Speed (m/s) 1.00 C 0.75 c 0.67 0.41 c 0.71 c n 1.00 1.33 1.50 Index of Refraction n of a given medium is defined as the ratio of speed of light in vacuum, c to the speed of light in a medium, v. n = c/v

Table-4: Incident Angle (degrees) Reflected Angle Refracted angle (degrees) (degrees) % Intensity of reflected ray 0 10 20 30 40 50 N/A N/A N/A 30 40 50 0 11.3 22.7 34.2 46.3 59.5 N/A N/A N/A 0.67 1.22 3.08 % Intensity of refracted ray 100 100 100 99.33 98.78 96.92

When rays travel from a denser medium to a less dense medium, we can define a critical angle of incidence θ such that refracted angle θ₂ = 90°. Applying Snell's law: Critical angle θ = sin-1(n₂/n₁).

When the angle of incidence is greater than the critical angle, 100% of the light intensity is reflected. This is called total internal reflection because all the light is reflected.

15. Calculate the critical angle of glass and water combination. Show your calculation.

16. What is the critical angle for the interface between Mystery A and glass?

Explanation:

15.  Applying Snell's law; Critical angle θ = sin-1(n₂/n₁).

where n₂,refractive index of water = 1.33, n₁, refractive index of glass = 1.50 since glass is denser than water

θ = sin-1(1.33/1.50)

θ = 62.45°

Critical angle of glass and water combination, θ = 62.45°

16.  Refractive index of mystery A , n = c/v

where v = 0.41 c

therefore, n = c / 0.41 c = 2.44

Critical angle for the interface between Mystery A and glass, θ = sin-1(n₂/n₁).

where n₂,refractive index of glass = 1.50, n₁, refractive index of mystery A = 2.44 since mystery A is denser than glass as seen from its refractive index

θ = sin-1(1.50/2.44)

θ = 37.93°

Critical angle for the interface between Mystery A and glass, θ = 37.93°

Answer:

Part A

dispersion forces

Part B

dispersion forces

Part C

dispersion forces

dipole-dipole forces

Part D

dispersion forces

dipole-dipole forces

hydrogen bonding

Explanation:

Dispersion forces occur in all molecules. They result from momentary shifts in the electron cloud of molecules which induces a dipole in another molecule. This induced dipole eventually spreads throughout the molecule.

For Xe which is a noble gas and N2 which is a diatomic molecule, dispersion forces is the only kind of intermolecular force present in the molecule.

CO is a polar molecule hence in addition to dispersion forces, dipole-dipole forces also exist in the molecule.

HF is a polar molecule hence it possesses dipole-dipole forces in addition to dispersion forces. In this molecule, hydrogen is bonded to a highly electronegative atom (fluorine). Hence, hydrogen bonding is a dominant intermolecular interaction in the molecule.

Answer:

D. Reduction takes place at the cathode, which is negatively charged.

Explanation:

In an electrolytic cell there are two electrodes; the cathode and the anode. The anode is the positive electrode while the cathode is the negative electrode. Oxidation occurs at the anode while reduction occurs at the cathode.

At the anode, species give up electrons and become positively charged ions while at the cathode species accept electrons and become reduced.