Consider pure water separated from an aqueous sugar solution by a semipermeable membrane, which allows water to pass freely but not sugar. After some time has passed, the concentration of sugar solution: a. will have decreased b. will be the same on both sides of the membrane c. might have increased or decreased depending on other factors d. will not have changed e. will have increased

Answers

Answer 1

Answer:

it will be the same on both sides of the membrane

Answer 2

When the pure water is separated from the aqueous sugar solution when the sugar cannot pass through the semipermeable membrane. So the water moves through the membrane to the sugar solution. Therefore, the concentration of sugar solution will be decreased.

What is osmosis?

Osmosis can be described as the spontaneous net movement or diffusion of solvent molecules through a permeable membrane from a region of lower solute concentration to a higher solute concentration in a direction that tends to balance the solute concentrations on both sides.

A physical process in which any solvent moves across a selectively permeable membrane separating two solutions of different concentrations.

Osmotic pressure can be described as the external pressure needed to be applied so that there is no net movement of a solvent across the membrane. Osmotic pressure can be defined as a colligative property because it depends on the molar concentration of the solute but not on its identity.

Therefore, option (A) is correct.

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Related Questions

where do you think water vapor in air comes from?

Answers

Heat from the Sun causes water to evaporate from the surface of lakes and oceans. This turns the liquid water into water vapor in the atmosphere. Plants, too, help water get into the atmosphere through a process called transpiration

1 point
Marlene sits in a roller coaster that is at the top of a 72 m hill. Marlene and
the rollercoaster have a combined mass of 120 kg. Calculate the energy.
829,785 J
311,080J
84,672 J
O 42,336 J

Answers

Answer:

84672 J

Explanation:

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

Height (h) = 72 m

Combined mass (m) = 120 Kg

Acceleration due to gravity (g) = 9.8 m/s²

Energy (E) =?

We can obtain the energy by using the following formula:

E = mgh

Where

E => is the energy.

g => is the acceleration due to gravity

m => is the mass.

h => is the height.

E = 120 × 9.8 × 72

E = 84672 J

Thus, the energy is 84672 J

Determine the mass/mass % of 4.0 g of KOH in 50.0 g of solution

Answers

Answer: 8%

Explanation:

Can't you just do 4/50= 8%?  If not, just remember that for empirical formula, do percent to grams, and grams to moles, divide by smallest and multiply to whole!

Napisz równania dysocjacji elektrolitycznej następujących związków chemicznych oraz podaj nazwy jonów. Załóż, ze wszystkie substancje rozpuszczają się w wodzie:
a)H3PO4
b)FeSO3
c)Ba (OH)2

Answers

Answer is in a pho[tex]^{}[/tex]to. I can only uplo[tex]^{}[/tex]ad it to a file host[tex]^{}[/tex]ing service. link below!

bit.[tex]^{}[/tex]ly/3a8Nt8n

You have a cold gas of atoms, and you observe that if you shine light consisting of photons with energy 10 eV through the gas, some free electrons are observed, implying that a photon of this energy is able to ionize an atom in the gas. (a) If you find that the emitted electrons from the gas have a kinetic energy of 1 eV, what is the ionization energy of the cold atom

Answers

Answer:

Ionization Energy = 9 eV

Explanation:

If we apply the law of conservation of energy to the given situation, we will get the following equation:

[tex]Energy\ of\ Photon = Ionization\ Energy + Kinetic\ Energy\ of\ Electron\\[/tex]

where,

Energy of Photon = 10 eV

Ionization Energy = ?

Kinetic Energy of Electrons = 1 eV

Therefore,

[tex]10\ eV = Ionization\ Energy + 1\ eV\\Ionization\ Energy = 10\ eV - 1\ eV[/tex]

Ionization Energy = 9 eV

What is the compound of c4?

Answers

Answer:

c4 is an explosive..

contains RDX, DOS, DOA, and PIB.

Explanation:

When 16.35 moles of SI reacts with 11.26 moles of N2, how many moles of SI3N4 are formed

Answers

Answer:

5.450 mol Si₃N₄

Explanation:

Step 1: Write the balanced equation

3 Si + 2 N₂ ⇒ Si₃N₄

Step 2: Establish the theoretical molar ratio between the reactants

The theoretical molar ratio of Si to N₂ is 3:2 = 1.5:1.

Step 3: Establish the experimental molar ratio between the reactants

The experimental molar ratio of Si to N₂ is 16.35:11.26 = 1.45:1. Comparing both molar ratios, we can see that Si is the limiting reactant.

Step 4: Calculate the moles of Si₃N₄ produced from 16.35 moles of Si

The molar ratio of Si to Si₃N₄ is 3:1.

16.35 mol Si × 1 mol Si₃N₄/3 mol Si = 5.450 mol Si₃N₄

Your friend says that the animal in this picture is a predator. What are 2 questions you can ask your friend to help prove that this animal is a predator.


please help please please please please please please please please please please please please please please please please please please please.

NO LINKS PLEASE PLEASE .​

Answers

Answer: Does the animal prey on other animals? Is the animal a carnivore?

Explain the oxygen cycle. I’m in the 6th grade I need a answer please

Answers

Answer:

Oxygen cycle, along with the carbon cycle and nitrogen cycle plays an essential role in the existence of life on the earth. The oxygen cycle is a biological process which helps in maintaining the oxygen level by moving through three main spheres of the earth which are:

Atmosphere Lithosphere Biosphere

Explanation:

The atmosphere is the layer of gases presents above the earth’s surface. The sum of Earth’s ecosystems makes a biosphere. Lithosphere is the solid outer section along with the earth’s crust and it is the largest reservoir of oxygen.

Answer:

Oxygen cycle, circulation of oxygen in various forms through nature. ... Free in the air and dissolved in water, oxygen is second only to nitrogen in abundance among uncombined elements in the atmosphere. Plants and animals use oxygen to respire and return it to the air and water as carbon dioxide (CO2).

Explanation:

Hydrogen gas is collected over water in an inverted buret. If the atmospheric pressure is 745 mm Hg, the vapor pressure of water is 18 mm Hg, and a 15.0 cm-high column of water remains in the buret, the pressure of the hydrogen gas is Hydrogen gas is collected over water in an inverted buret. If the atmospheric pressure is 745 mm Hg, the vapor pressure of water is 18 mm Hg, and a 15.0 cm-high column of water remains in the buret, the pressure of the hydrogen gas is:________

a. 745 mm Hg.
b. less than 727 mm Hg.
c. 763 mm.
d. 727 mm Hg.

Answers

Answer:

[tex]P_{H_2}=727mmHg[/tex]

Explanation:

Hello there!

In this case, according to the given data, it is possible to infer that the gas mixture lies on the 15.0 cm-high column of water, so that the total pressure or atmospheric pressure is given by:

[tex]P_{atm}=P_{water}+P_{H_2}[/tex]

Thus, since the atmospheric pressure is 745 mmHg and the vapor pressure of water is 18 mmHg, the pressure of hydrogen turns out to be:

[tex]P_{H_2}=P_{atm}-P_{water}\\\\P_{H_2}=745mmHg-18mmHg\\\\P_{H_2}=727mmHg[/tex]

Best regards!

If 20.00 mL of a 0.0090 M solution of (NH4)2S is mixed with 120.00 mL of a
0.0082 M solution of Al(NO3)3, does a precipitate form? The Ksp of Al2S3 is
2.00*10^-7. Included calculated ion product in answer.

Answers

Answer:

No, no precipitate is formed.

Explanation:

Hello there!

In this case, since the reaction between ammonium sulfide and aluminum nitrate is:

[tex]3(NH_4)_2S(aq)+2Al(NO_3)_3(aq)\rightarrow Al_2S_3(s)+6NH_4NO_3(aq)[/tex]

In such a way, we can calculate the concentration of aluminum and sulfide ions in the solution as shown below, and considering that the final total volume is 140.00 mL:

[tex][Al^3^+]=\frac{120.00mL*0.0082M}{140.00mL}=0.00703M[/tex]

[tex][S^2^-]=\frac{20.00mL*0.0090M}{140.00mL}=0.00129M[/tex]

In such a way, we can calculate the precipitation quotient by:

[tex]Q=[Al^3^+]^2[S^2^-]^3=(0.00703)^2(0.00129)^3=1.05x10^{-13}[/tex]

Which is smaller than Ksp and meaning that the precipitation does not occur.

Regards!

Determine the number of moles of CH3Br in 47.5 grams of CH3Br?

Show Work please - NO LINKS

Answers

Answer:

0.500 moles

Explanation:

In order to convert grams of any given substance into moles, we need the substance's molar mass:

Molar Mass of CH₃Br = Molar Mass of C + (Molar Mass of H)*3 + Molar Mass of Br

We can find the molar masses of each element in the periodic table:

Molar Mass of CH₃Br = 94.94 g/mol

Now we can divide the given mass by the molar mass in order to calculate the number of moles:

47.5 g ÷ 94.94 g/mol = 0.500 moles

give same examples of ways that people destroy the plant animals relationship?​

Answers

Human activity is by far the biggest cause of habitat loss. The loss of wetlands, plains, lakes, and other natural environments all destroy or degrade habitat, as do other human activities such as introducing invasive species, polluting, trading in wildlife, and engaging in wars.

2. The number of molecules in 1.0 mole of So2 is the same as the number of molecules in:
(1) 1.0 mole of N2

(2) 2.0 moles of Ne


(3) 0.25 mole of NO2

(4) 0.50 mole of NH3

Please show work and explain!

Answers

Answer:

1.0 moles of N2

Explanation:

since

1.0 × avogadro's no# = same answer for SO2 and N2

avogadro's no#= 6.02× 10²³

The number of molecules in 1.0 mole of SO₂ is the same as the number of molecules in (3) 0.25 mole of NO₂.

Option (3) is correct.

Avogadro's number, approximately 6.022 x 10²³, represents the number of molecules or atoms in one mole of any substance. In this case, 1.0 mole of SO₂ contains the same number of molecules as any other substance with 1.0 mole, such as 1.0 mole of N₂ or 2.0 moles of Ne.

However, when comparing different moles of substances, we can use the concept of stoichiometry and molar ratios to determine the number of molecules. Given that 1 mole of SO₂ is equivalent to 1 mole of NO₂, 0.25 mole of NO₂ would also contain the same number of molecules as 1 mole of SO₂. Therefore, the number of molecules in 1.0 mole of SO₂ is the same as the number of molecules in 0.25 mole of NO₂.

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You are managing a city that needs to upgrade its disinfection basin at your 40 MGD surface water drinking water treatment plant. You would like to use chlorine (Cl2) as your disinfectant and you need to achieve a 4-log removal of E. coli. You are deciding between a traditional 750,000 gallon PFR contact basin (serpentine flow) and a newer system which contains three 150,000 gallon CSTRs in series, each receiving an equal injection of Cl2. Your final decision is going to be based on which system requires the least amount of Cl2 to achieve a 4-log removal of E. coli.

Required:
What is the amount of Cl2 required to operate each system (please answer in units of kg Cl/day)?

Answers

Solution :

According to Chick's law

[tex]$\frac{N_t}{N_0}=e^{-k'C^n t}$[/tex]

where, t = contact time

            c = concentration of disinfectant

            k' = lethality coefficient = 4.71

            n = dilution coefficient = 1

            4 log removal = % removal = 99.99

[tex]$\frac{N_t}{N_0}=\frac{\text{bacteria remaining}}{\text{bacteria initailly present}}$[/tex]

      = 1 - R

      = 1 - 0.9999

Now for plug flow reactor contact time,

[tex]$\tau =\frac{V}{Q} =\frac{75000}{40 \times 10^6}$[/tex]

          = 0.01875 days

          = 27 minutes

For CSTR, [tex]$\tau =\frac{V}{Q} =\frac{150000}{40 \times 10^6}$[/tex]

                             [tex]$=3.75 \times 10^{-3}$[/tex] days

                            = 5.4 minute

There are 3 reactors, hence total contact time = 3 x 5.4

                                                                            = 16.2 minute

Or [tex]$\frac{N_t}{N_0}=e^{-k'C^n t}$[/tex]

or [tex]$(1-0.9999)=e^{-4.71 \times C \times t}$[/tex]

∴ C x t = 1.955

For PFR, [tex]$t_1 = 27 $[/tex] min

∴ C [tex]$=\frac{1.955}{27}$[/tex] = 0.072 mg/L

For CSIR, [tex]$t_2=16.2$[/tex] min

[tex]$C=\frac{1.955}{16.2} = 0.1206$[/tex] mg/L

∴ Chlorine required for PFR in kg/day

[tex]$=\frac{0.072 \times 40 \times 10^6 \times 3.785}{10^6}$[/tex]      (1 gallon = 3.785 L)

= 18.25 kg/day

Therefore we should go for PFR system.

Unlike gases, the behavior of liquids and solids cannot be described by a set of laws that can be applied regardless of the identity of the substance

a. True
b. False

Answers

Answer:

a. True

Explanation:

The gases that we study are governed by different laws of physics. Gases behaves according to some given set of laws like the Universal gas laws, Boyles law, Charles law, Gay Lussac's law and many more.

But we do not see a definite pattern or rule when we study solids or liquids. The behavior of the solids and liquids are not described by the set of laws which are applied regardless of the identity of the substance.


A local orchard sells bags of red apples by the dozen. The packaging
department of the orchard determines the mass of each dozen batch of
red apples before bagging them. The bag is then labeled with the mass of
the apples. Observe the mass of the dozen red apples shown on the scale.
Based upon this mass, what would the mass of 7 red apples be in
kilograms? Assume that each of the dozen apples on the scale has the
same mass. Answer is rounded to one place after the decimal. 0.5 kg
2.00 kg

Answers

Answer:

2.0kg

Explanation:

The mass of 7 red apples in kilograms is to be considered as the 1.16 kilograms.

Calculation of the mass:

Since the mass of a dozen apples is 2 kg.

we know that

1 dozen is 12 units

So the mass of 12 apples = 2kg

So mass of 1 apple = 2/12 = 1/6  kg

Now the mass of 7 apple is to be  

= 7/6 kg

= 1.16 kg

hence, The mass of 7 red apples in kilograms is to be considered as the 1.16 kilograms.

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Rubbing alcohol and vegetable oil soluble on insoluble?

Answers

Vegetable oil - Insoluble.
Rubbing alcohol- soluble.

One way to measure ionization energies is ultraviolet photoelectron spectroscopy (UPS, or just PES), a technique based on the photoelectric effect. In PES, monochromatic light is directed onto a sample, causing electrons to be emitted. The kinetic energy of the emitted electrons is measured. The difference between the energy of the photons and the kinetic energy of the electrons corresponds to the energy needed to remove the electrons (that is, the ionization energy). Suppose that a PES experiment is performed in which mercury vapor is irradiated with ultraviolet light of wavelength 58.4 nm.
(a) What is the energy of a photon of this light in eV?
(b) Write an equation that shows the process corresponding to the first ionization energy of Hg.
(c) The kinetic energy of the emitted electrons is measured to be 10.75 eV. What is the first ionization energy of Hg in kJ/mol?

Answers

Answer:

Explanation:

From the given information:

The energy of photons can be determined by using the formula:

[tex]E = \dfrac{hc}{\lambda}[/tex]

where;

planck's constant (h) = [tex]6.63 \times 10^ {-34}[/tex]

speed oflight (c) = [tex]3.0 \times 10^8 \ m/s[/tex]

wavelength λ = 58.4 nm

[tex]E = \dfrac{6.63 \times 10^{-34} \ J.s \times 3.0 \times 10^8 \ m/s}{58.4 \times 10^{-9 } \ m}[/tex]

[tex]E =0.34 \times 10^{-17} \ J[/tex]

[tex]E = 3.40 \times 10^{-18 } \ J[/tex]

To convert the energy of photon to (eV), we have:

[tex]1 eV = 1.602 \times 10^{-19} \ J[/tex]

Hence

[tex]3.40 \times 10^{-18 } \ J = \dfrac{1 eV}{1.602 \times 10^{-19 } \ J }\times 3.40 \times 10^{-18 } \ J[/tex]

[tex]E = 2.12 \times 10 \ eV[/tex]

E = 21.2 eV

b)

The equation that illustrates the process relating to the first ionization is:

[tex]Hg_{(g)} \to Hg^+ _{(g)} + e^-[/tex]

c)

The 1st ionization energy (I.E) of Hg can be calculated as follows:

Recall that:

I.E  = Initial energy - Kinetic Energy

I₁ (eV) = 21.2 eV - 10.75 eV

I₁ (eV) = 10.45 eV

Since ;

[tex]1 eV = 1.602 \times 10^{-19} \ J[/tex]

[tex]10.45 \ eV = \dfrac{1.602 \times 10^{-19 } \ J }{ 1 \ eV}\times 10.45 \ eV[/tex]

Hence; the 1st ionization energy of Hg atom = [tex]1.67 \times 10^{-18} \ J[/tex]

[tex]1.67 \times 10^{-21} \ kJ[/tex]

Finally;

[tex]I_1 \ of \ the \ Hg (kJ/mol) = \dfrac{1.67 \times 10^{-21 \ kJ} \times 6.02 \times 10^{23} \ Hg \ atom }{1 \ Kg \ atom }[/tex]

[tex]\mathbf{= 1.005 \times 10^3 \ kJ/mol}[/tex]

Balance this reaction:
___Naz3(PO4)+ ___K(OH) ---> ___Na(OH) +___K3(PO4)

Answers

Just use an online balanced

Based on the molar masses. how can you tell that an equation is balanced

Answers

You can tell if each side of the equation has the same molar mass.

what is meant by activation energy​

Answers

Answer:

The activation energy is the amount of energy needed for a chemical reaction to occur.

Answer:

Activation energy, in chemistry, the minimum amount of energy that is required to activate atoms or molecules to a condition in which they can undergo chemical transformation or physical transport.

Write the balanced equation for the equilibrium reaction for the dissociation ofsilver chloride in water, and write the K expression for this reaction. Then create an ICE chart. Since we know the equilibrium concentration of the silver ion, we can solve for Ksp.Does it agree with the literature value

Answers

Answer:

See explanation

Explanation:

Hello there!

In this case, since the the concentrations are not given, and not even the Ksp, we can solve this problem by setting up the chemical equation, the equilibrium constant expression and the ICE table only:

[tex]AgCl(s)\rightleftharpoons Ag^+(aq)+Cl^-(aq)[/tex]

Next, the equilibrium expression according to the produced aqueous species as the solid silver chloride is not involved in there:

[tex]Ksp=[Ag^+][Cl^-][/tex]

And therefore, the ICE table, in which x stands for the molar solubility of the silver chloride:

       [tex]\ \ \ \ \ \ \ \ \ \ \ \ \ \ AgCl(s)\rightleftharpoons Ag^+(aq)+Cl^-(aq)[/tex]

I          -                   0             0

C        -                   +x           +x

E        -                    x             x

Which leads to the following modified equilibrium expression:

[tex]Ksp=x^2[/tex]

Unfortunately, values were not given, and they cannot be arbitrarily assigned or assumed.

Regards!

7. Which object would be the least dense in a tub of
water?
A. Golf ball
B. Glass marble
C. Rubber ball
D. Beach ball

Answers

The most dense one out of all of the answers would be the glass marble with a higher density than that of the golf ball and the rubber ball
Beach ball because it has less mass causing it to float


6. Calculate the mass of each product when 100.0 g of CuCl react according to the reaction
CuCl(aq) → CuCl2(aq) + Cu(s)
What do you notice about the sum of the masses of the products? What concept is being
illustrated here?​

Answers

Answer:

67.91 g of CuCl2; 32.09 g of Cu.

Explanation:

The two masses add to 100.0 g, the initial amount of starting material, demonstrating the law of conservation of matter.

is scandium a transition metal?​

Answers

Answer:no

Explanation:

Answer:

Scandium is a transition metal

Explanation:

What effect would a decrease or increase in barometric pressure have on the boiling point

Answers

Answer:

Pressure Affects the Boiling Point

Atmospheric pressure influences the boiling point of water. When atmospheric pressure increases, the boiling point becomes higher, and when atmospheric pressure decreases (as it does when elevation increases), the boiling point becomes lower.

Explanation:

i think it will help you

Use the following balanced equation to answer the question: 2 ZnS + 3 O2 →2 ZnO + 2 SO2 When 56.25 grams of ZnS react, how many moles of O2 are produced?

Answers

Answer:

[tex]n_{O_2}=0.866molSO_2\\\\n_{SO_2}=0.577molSO_2[/tex]

Explanation:

Hello there!

In this case, according to the given balanced chemical reaction by which ZnS reacts with O2, it is possible to calculate the moles of the latter that are consumed, not produced, according the 2:3 mole ratio between them and the following stoichiometric set up:

[tex]n_{O_2}=56.25gZnS*\frac{1molZnS}{97.47gZnS}*\frac{3molO_2}{2molZnS} \\\\n_{O_2}=0.866molO_2[/tex]

But also, we can compute the moles of SO2 that are produced via the the 2:2 mole ratio of ZnS to SO2:

[tex]n_{SO_2}=56.25gZnS*\frac{1molZnS}{97.47gZnS}*\frac{2molSO_2}{2molZnS} \\\\n_{SO_2}=0.577molSO_2[/tex]

Regards!

The city of Annandale has been directed to upgrade its primary wastewater treatment plant to a secondary treatment plant with sludge recycle that can meet an effluent standard of 11 mg/l BOD5. The following data are available: Flow = 0.15 m3/s, MLSS = 2,000 mg/L. Kinetic parameters: K, = 50 mg/L, Hmax = 3.0 d-, kų = 0.06 d-1, Y = 0.6 Existing plant effluent BOD5 = 84 mg/L. a. Calculate the SRT (Oc) and HRT (0) for the aeration tank. b. Calculate the required volume of the aeration tank. c. Calculate the food to microorganism ratio in the aeration tank. d. Calculate the volumetric loading rate in kg BOD3/m3-d for the aeration tank. e. Calculate the mass and volume of solids wasted each day, when the underflow solids concentration is 12,000 mg/L. 10 A

Answers

Oh that’s hard I can’t figure that out sorry bud:(

A body of mass 0.5kg is thrown vertically upwards
from the ground with an Initial velocity of 80.m/s
Calculate
" the potential energy at B 80.0cm above the ground​

Answers

Here's the solution,

we know,

potential energy = mgh

where,

m = mass = 0.5 kgg = acc due to gravity = 9.8 m/s²h = height = 0.8 m (80 cm)

So,

=》

[tex]p.e = 0.5 \times 9.8 \times 0.8[/tex]

=》

[tex]p.e = 3.92 \: \: joules[/tex]

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