Hydrofluoric acid and Water react to form fluoride anion and hydronium cation, like this HF(aq) + H_2O(l) rightarrow F(aq) + H_3O^+ (aq) At a certain temperature, a chemist finds that a 5.6 L reaction vessel containing an aqueous solution of hydrofluoric acid, water, fluoride anion, and hydronium cation at equilibrium has the following composition: Calculate the value of the equilibrium constant K_C for this reaction. Round your answer to 2 significant digits. K_C =

Answer:

When an alkyl benzene is heated with strong oxidizing asgents like acidic or alkline KMnO4

or acidified K2Cr2O7

, etc. gives aromatic carboxyllic acid. The alkyl side chain gets oxidised to −COOH

group irrespective of the size of the chain.

Explanation:

Answer:

[NaCl(aq)] = 0.25M

Explanation:

Molarity = moles solute / volume of solution in liters

moles NaCl in 29.25 grams = 29.25g/58g·mol⁻¹ = 0.5043 mole

Molarity = 0.5043 mole NaCl / 2 Liters = 0.2555M ≅ 0.25M (2 sig-figs)

Answer:

A. When two aqueous solutions are mixed, a precipitate is formed.

Explanation:

The precipitate (a solid substance that falls from the liquid) is the result of a chemical reaction taking place between the liquids.

The other three answer choices are indicative of physical changes (temperature change, phase change, color change).

When two aqueous solutions are mixed, a precipitate is formed indicates that a chemical change has occurred.  

Hence, option A is correct answer.

Chemical change are those changes in which substance changes chemical composition. These changes are permanent changes. In chemical change new substances formed and in chemical change substances can not get back into its original form. It is irreversible change.

Physical changes are those changes in which substance changes physical properties only. Properties like temperature, pressure, shape, color, size, state (solid, liquid and gas). These changes are temporary in nature. In physical change no new substances formed. It is reversible change.

Now, check all the options one by one:

Option (A): When two aqueous solutions are mixed, a precipitate is formed is a chemical change. Since precipitation indicate a chemical reaction (that is double displacement reaction).

Option (B): As ammonium nitrate dissolved in water causes the temperature to decrease is a physical change because heat energy is absorbed here and it is a endothermic reaction.

Option (C): Alcohol evaporates when left in an open container is a physical change because evaporation is a physical change as it changes the state from liquid state to gas state.

Option (D): Water is added to blue copper (II) chloride solution. The resulting mixture if lighter blue in color is a physical change as properties like change in color is physical change.  

Thus, from above conclusion we can say that When two aqueous solutions are mixed, a precipitate is formed indicates that a chemical change has occurred.  

Hence, option A is correct answer.

Learn more about physical and chemical change here: https://brainly.com/question/17166994

#SPJ2

Answer:

Due to the circulation of the wind and water the trash will continue to go around in a circle thus causing it to be trapped there.

Answer:

2 no. is the answer surface currents that move in a path opposite to the wind currents

Answer:

no.2 is the answer of your question

Answer:

73.2 pm

Explanation:

"The anions make contact along the diagonal of the face of the unit cell, so the diagonal of the face is equal to 4 ionic anion radii. By letting r represent the ionic radius of the anion, d represent the diagonal of the face of the unit cell, and x represent the edge length, then d=4r and

d^2=x^2+x^2=  2x^2

By substituting 4r for d, the second equation becomes

(4r)^2=(2)x^2

Solving this equation for r shows that

r=(x–√2)/4

Since the edge length x is 207 pm, the ionic radius of the anion is

r= ((207 pm) X [tex]\sqrt{2}[/tex])/4=73.2 pm

Notice that the formulae used to describe atomic radii include constants with exact values. Therefore, these values do not constrain the number of significant figures."

The ionic radius of the anion in the FCC unit cell where anions are in contact along the diagonal of the face of the unit cell is 73.1pm.

Ionic radius is the distance between the center of the atom and the outermost part.

As in the question it is given that anions are in contact along the diagonal of the face of the unit cell, so the length of the diagonal is represented as: d = 4r, where

r = ionic radius

Length of edge i.e. a = 207 pm (given)

Two adjacent edges and diagonal of a FCC unit cell makes a right angle triangle, by using pythagoras theorem we can write as:

a² + a² = d²

2a² = (4r)²

2a²/16 = r²

2(207)²/16 = r²

85,698/16 =  r²

0r r = 73.18 pm

Hence, 73.18 pm is the ionic radius of the anion.

To learn more about ionic radius, visit the below link:

https://brainly.com/question/8137711

Answer: A person engaged in the practice of anthropology. Anthropology is the study of aspects of humans within past and present societies. Social anthropology, cultural anthropology and philosophical anthropology study the norms and values of societies.

Explanation: I HOPE THIS HELPS U AND ANSWERS UR QUESTION!!! Stay safe and healthy!

Answer:

I think it is copper

Explanation:

.........................

Answer:

copper

Explanation:

Answer:

2 N

Explanation:

Answer:

molar mass of H2CO3 = 72.0228

Answer:

62.02 g/mol

Explanation:

Took the test and got it right. if you have enough faith in brainly youll choose the right answer

Answer:

5.916x10⁻³ mol OH⁻

Explanation:

The reaction that takes place is:

First we calculate the added moles of each reagent, using the given volumes and concentrations:

Now we calculate how many KOH moles reacted with 3.967 mmol H₂SO₄:

Finally we calculate how many OH⁻ moles remained after the reaction

Answer:

1.used to seperate solids from liquids, and is a act of pouring a mixture onto a membrane this allows the passage of liquid and results in the collection of a solid

2. the solution would passed through without losing and solids

3 would allow them to dry or on further hearing decompose

Explanation:

Answer:

the scientific name is Angiosperms

Explanation:

please mark brainliest

Answer:

Yes

Explanation:

The point of greenhouse gases is that it absorbs and emits radiant energy within the thermal infrared range and causes it to be trapped.

5.55 mol C₂H₅OH

Math

Pre-Algebra

Order of Operations: BPEMDAS

Chemistry

Atomic Structure

Stoichiometry

Step 1: Define

[RxN - Balanced] C₆H₁₂O₆ → 2C₂H₅OH + 2CO₂

[Given] 500. g C₆H₁₂O₆ (Glucose)

[Solve] moles C₂H₅OH (Ethanol)

Step 2: Identify Conversions

[RxN] 1 mol C₆H₁₂O₆ → 2 mol C₂H₅OH

[PT] Molar mass of C - 12.01 g/mol

[PT] Molar Mass of H - 1.01 g/mol

[PT] Molar Mass of O - 16.00 g/mol

Molar Mass of C₆H₁₂O₆ - 6(12.01) + 12(1.01) + 6(16.00) = 180.18 g/mol

Step 3: Stoichiometry

Step 4: Check

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

5.55001 mol C₂H₅OH ≈ 5.55 mol C₂H₅OH

Answer: Polarity, Boiling and Freezing Points, Specific Heat Capacity, Density, Surface Tension, Heat of Vaporization and Vapor Pressure, Capillary Action, Solid State (Ice), Liquid State (Liquid Water), Gas State (Steam),  

Explanation:  Water molecules are polar, so they form hydrogen bonds. This gives water unique properties, such as a relatively high boiling point, high specific heat, cohesion, adhesion, and density.

Answer: true

Explanation:

Thermal efficiency of process heating equipment

Answer:

C

Explanation:

Wind is geological therefore it is geological weathering

Answer: A> B> C > D> E

Explanation:

pH or pOH is the measure of acidity or alkalinity of a solution.

pH is calculated by taking negative logarithm of hydrogen ion concentration.

[tex]pH=-\log [H^+][/tex]

a) Solution A: pH =2  

[tex][H^+]=10^{-2}[/tex]

b) Solution B: pH =5  

[tex][H^+]=10^{-5}[/tex]

c) Solution C: pH = 7  

[tex][H^+]=10^{-7}[/tex]

d) Solution D: pH = 8  

[tex][H^+]=10^{-8}[/tex]

e) Solution E: pH =13

[tex][H^+]=10^{-13}[/tex]

Thus the decreasing order of hydrogen ion concentration is A> B> C > D> E

Solution :

For the reaction given :

[tex]$\text{2Hg}_{(l)}+\text{O}_2_{(g)} \rightarrow \text{2HgO}_{(s)}$[/tex]

Thus we know that the equilibrium constant [tex]$K_c$[/tex] contains aqueous an dgas species only.

∴       [tex]$K_c=\frac{1}{[O_2]}$[/tex]    ............(1)

Now at the equilibrium, an amount of the 13.4 g of oxygen was found in the vessel of 6.9 liters. For determining the concentration of the oxygen gas, we use :

[tex]$[O_2]= \frac{n_{O_2}}{V_{soln}}$[/tex]  ...................  (2)

Here, [tex]$n_{O_2}$[/tex] = no. of moles of oxygen gas (mol)

         [tex]$V_{soln}$[/tex] = volume of solution (L)

Therefore the number of moles of the oxygen gas is calculated by directly using the molecular weight (31.9988 g/mol) as the conversion factor.

∴      [tex]$n_{O_2}= 13.4 \ g \times \frac{\text{1 mol}}{31.9988 \ g}$[/tex]

              = 0.418 mol

Now substituting the known values in (2), we can find the equilibrium concentration of the oxygen gas :

[tex]$[O_2] =\frac{0.418 \ \text{mol}}{6.9 \ \text{L}}$[/tex]

     = 0.0605 M

Therefore substituting the result in (1), the equilibrium constant for the reaction is :

[tex]$K_c=\frac{1}{0.0605}$[/tex]

    = 16.52

Answer:

11. Polonium.

12. Argon.

Explanation:

In Chemistry, electrons can be defined as subatomic particles that are negatively charged and as such has a magnitude of -1.

Valence electrons can be defined as the number of electrons present in the outermost shell of an atom. Valence electrons are used to determine whether an atom or group of elements found in a periodic table can bond with others. Thus, this property is typically used to determine the chemical properties of elements.

11. Polonium: this metalloid has 6 valence electrons and 6 electron shells. It has 84 electrons with 6 shell structure 2, 8, 18, 32, 18, 6.

Therefore, polonium has the following electronic configuration;

Polonium = 1s² 2s² 2p² 3s² 3p6 3d10 4s² 4p6 4d10 5s² 5p6 4f¹⁴ 5d10 6s² 6p⁴

12. Argon: this element has the same number of electrons as a Sulfur ion. It has 18 electrons.

Answer:

Explanation:

A graduated cylinder was filled to 30.0 mL with a liquid. An unknown metal cylinder having a mass of 60.27 g was submerged in the in the liquid. The final volume of the liquid level was 45.2 mL.

a. Calculate the density of the unknown metal cylinder.

b. The density of the liquid is 0.899 g/mL. What is the mass of the liquid in the graduated cylinder?

Answer:

Answer is B

Explanation:

It's not A because we're boiling only water.

It's not C because the last dot for 2 cups ends at 70 min while the last dot for 4 cups ends at 90 min.

It's not D because water boils at around 100 C, as shown in the graph. The highest dot for both 2 cups and 4 cups were about the same near 100 C.

The graph shows that 4 cups of water is able to retain heat more (higher heat capacity), so it takes more time for water to cool down than 2 cups of water.

The question is incomplete, the complete question is;

Draw Lewis structures for the following compounds/ions.

Decide if the compound/ion listed can satisfy the octet rule (duet rule for H), if so choose Satisfies Octet Rule from the drop down menu.

If the compound/ion cannot satisfy the octet rule for one of the atoms in the formula, choose one of the following three reasons why;

Too many valence electrons (more than eight), Too few valence electrons (fewer than eight), or Odd # of valence electrons.

Satisfies Octet Rule Too many valence electrons Too few valence electrons Odd # of valence electrons  KrCl2

Satisfies Octet Rule Too many valence electrons Too few valence electrons Odd # of valence electrons  PCl3

Satisfies Octet Rule Too many valence electrons Too few valence electrons Odd # of valence electrons  BeH2

Satisfies Octet Rule Too many valence electrons Too few valence electrons Odd # of valence electrons  NO3-

Satisfies Octet Rule Too many valence electrons Too few valence electrons Odd # of valence electrons  SeO22-

Satisfies Octet Rule Too many valence electrons Too few valence electrons Odd # of valence electrons  SO2

Answer:

See explanation

Explanation:

Let us consider the number of valence electrons in each of the species. This will let us know whether the specie satisfies the octet rule or not.

KrCl2 has a total of 22 valence electrons. This implies that there are too many valence electrons hence the compound does not satisfy the octet rule.

For PCl3, there are 26 valence electrons. This compound satisfies the octet rule.

For BeH2, there are four valence electrons. This number of valence electrons is too few hence BeH2 does not satisfy the octet rule.

NO3^- has 24 valence electrons and is represented using resonance structures. Its resonance structures show that the specie satisfies the octet rule.

SeO2^2- has 20 valence electrons. This specie satisfies the octet rule.

SO2 has 18 valence electrons and is represented by resonance structures which satisfy the octet rule.

Answer:

2) 0.4 mol

Explanation:

Step 1: Given data

Step 2: Convert "V" to L

We will use the conversion factor 1 L = 1000 mL.

500 mL × 1 L/1000 mL = 0.500 L

Step 3: Calculate the moles of KBr (solute)

The molarity is the quotient between the moles of solute (n) and the liters of solution.

M = n/V

n = M × V

n = 0.8 mol/L × 0.500 L = 0.4 mol