Select all the correct answers
When two generalizations can be made based on what you know about cycles of matter in a closed system?
New matter is added, and old matter is destroyed.
Matter changes its physical form, allowing it to return to its original state.
The amount of matter within the system remains the same
Matter and energy can cross the boundaries of the system.
The cycle has a well-defined starting and Stopping point

Select All The Correct AnswersWhen Two Generalizations Can Be Made Based On What You Know About Cycles

Answers

Answer 1

Answer:

A

Explanation:


Related Questions

A chemist requires a large amount of 1-bromo-4-phenyl-2-butene as starting material for a synthesis and decides to carry out the following NBS allylic bromination reaction in the presence of UV light. Draw the structures of all of the observed products.
NBS
(C6H5)CH2CH = CHCH3 → ?
CCI4
Draw one additional resonance structure for the species below:
CH3CH=CHCH=CHCH=CHCH2

Answers

Answer:

CH 2 CH 3 CHCH = C6H5 + 5 Hydrogen Atoms

I hope I helped you.

Deepest apologies if I was wrong!

Bye!

~ Myaka O.

identify the two functional groups in the following compound

Answers

Answer:

D. amine and alcohol

Explanation:

Organic compounds are identified using the functional group they contain. The functional group defines their peculiarity and chemical identity. For example, alkenes are identified by a double bond functional group (=), alcohols are identified by an hydroxyl functional group (OH) etc.

According to this question, a compound was given as an attached image. The compound posseses:

- an hydroxyl group (OH) indicating that it has an ALCOHOL functional group

- an N-H group indicating that it has an amine functional group

Question 11

1 pts

A solution is formed by dissolving 45 grams of NH4Cl in

100 grams of H20 at 70°C. Which statement correctly

describes this solution?

O NH4Cl is the solute, and the solution is saturated.

O NH4Cl is the solute, and the solution is unsaturated.

o NH4Cl is the solvent, and the solution is unsaturated.

O NH4Cl is the solvent, and the solution is saturated.

< Previous

Answers

Answer:

NH4Cl is the solute, and the solution is unsaturated.

Explanation:

To create a saturated solution of ammonium chloride at 70°C, we need to dissolve 62 g of ammonium chloride in 100 g of water.

The question tells us that 45 grams of NH4Cl was dissolved in 100 grams of H20 at 70°C. This creates an unsaturated solution since the amount of solute present is less than the amount of solute that the NH4Cl solution can normally hold at 70°C.

Hence, NH4Cl is the solute, and the solution is unsaturated.

In Denver, Colorado the elevation is about 5,280 feet above sea level. Explain what potential effects this may have on the solubility of a gaseous solute in a liquid solution.

Answers

Answer:

The solubility of the gaseous solute decreases

Explanation:

As we know, pressure decreases with altitude. This means that, at higher altitudes, the pressure is much lower than it is at sea level.

The solubility of a gas increases with increase in pressure and decreases with decrease in pressure.

Hence, in Denver, Colorado where the elevation is about 5,280 feet above sea level, a gaseous solute is less soluble than it is at sea level due to the lower pressure at such high altitude.

A 420 mL sample of a 0.100 M formate buffer, pH 3.75, is treated with 7 mL of 1.00 M KOH. What is the pH following this addition? (pKa for formic acid is 3.75)

Answers

Answer: The pH of the resulting solution will be 3.60

Explanation:

Molarity is calculated by using the equation:

[tex]\text{Molarity}=\frac{\text{Moles}}{\text{Volume}}[/tex] ......(1)

We are given:

Molarity of formic acid = 0.100 M

Molarity of potassium formate = 0.100 M

Volume of solution = 420 mL = 0.420 L (Conversion factor: 1 L = 1000 mL)

Putting values in equation 1, we get:

[tex]\text{Moles of formic acid}=(0.100mol/L\times 0.420L)=0.0420mol[/tex]

[tex]\text{Moles of potassium formate}=(0.100mol/L\times 0.420L)=0.042mol[/tex]

Molarity of KOH = 1.00 M

Volume of solution = 7 mL = 0.007 L

Putting values in equation 1, we get:

[tex]\text{Moles of KOH}=(1mol/L\times 0.007L)=0.007mol[/tex]

The chemical equation for the reaction of formic acid and KOH follows:

                 [tex]HCOOH+KOH\rightleftharpoons HCOOK+H_2O[/tex]

I:                   0.042     0.007       0.042

C:                -0.007    -0.007     +0.007

E:                  0.035         -           0.049

Volume of solution = [420 + 7] = 427 mL = 0.427 L

To calculate the pH of the acidic buffer, the equation for Henderson-Hasselbalch is used:

[tex]pH=pK_a+ \log \frac{\text{[conjugate base]}}{\text{[acid]}}[/tex] .......(2)

Given values:

[tex][HCOOK]=\frac{0.049}{0.427}[/tex]

[tex][HCOOH]=\frac{0.035}{0.427}[/tex]

[tex]pK_a=3.75[/tex]

Putting values in equation 2, we get:

[tex]pH=3.75-\log \frac{(0.049/0.427)}{(0.035/0.427)}\\\\pH=3.75-0.146\\\\pH=3.60[/tex]

Hence, the pH of the resulting solution will be 3.60

PLZZZ HELPPPPPPPPPPPPPPPP

Answers

The answer is B. 9.43.

10.003-0.57= 9.433

Because there is a 3 in the third decimal place and not a number above 5, the 0.03 isn’t rounded up and will remain a 3. This means that when the number is rounded it rounds so 9.43.

1. When the following oxidation-reduction reaction in acidic solution is balanced, what is the
lowest whole-number coefficient for Rb*(aq)?
Rb(s) + Sr?+(aq) → Rb+ (aq) + Sr(s)

Answers

Answer:

2Rb(s) + Sr^+(aq) → 2Rb^+ (aq) + Sr(s)

Explanation:

Rubidium has a more negative reduction potential (-2.98 V) compared to strontium (-2.89 V).

Hence, in a redox reaction involving rubidium and strontium, rubidium will be oxidized while strontium is reduced.

The balanced redox reaction equation is obtained from;

Oxidation half equation;

2Rb(s) ---->2Rb^+(aq) + 2e

Reduction half equation;

Sr^2+(aq) + 2e ----> Sr(s)

Overall reaction equation;

2Rb(s) + Sr^+(aq) → 2Rb^+ (aq) + Sr(s)

When stirred in 30°C water, 5 g of powdered potassium bromide, KBr, dissolves faster than 5 g of large crystals of potassium bromide. Which of the following best explains why the powdered KBr dissolves faster?
A. Potassium ions and bromide ions in the powder are smaller than potassium ions and bromide ions in the large crystals.
B. Powdered potassium bromide exposes more surface area to water molecules than large crystals of potassium bromide.
C. Fewer potassium ions and bromide ions have been separated from each other in the powder than in the crystals.
D. Powdered potassium bromide is less dense than large crystals of potassium bromide.

Answers

Answer:

B

Explanation:

Do diện tích tiếp xúc ở dạng bột cao hơn dạng tinh thể

A hydronium ion:______.a. has the structure H3O. b. is a hydrated hydrogen ion. c. is a hydrated proton.d. is the usual form of one of the dissociation products of water in solution.e. all the answers above are correct.

Answers

Answer:

e. all the answers above are correct.

Explanation:

A hydronium ion:

a. has the structure H₃O⁺. YES, this is the chemical formula of the hydronium ion.

b. is a hydrated hydrogen ion. YES, it is formed according to the equation:

H⁺ + H₂O ⇒ H₃O⁺

c. is a hydrated proton. YES, since proton is the name given to the hydrogen ion

d. is the usual form of one of the dissociation products of water in solution. YES, according to the following equation:

2 H₂O ⇒ H₃O⁺ + OH⁻

Calcular el pH de una disolución cuando 10 g de NaOH se diluyen con agua hasta un volumen final de 250 ml

Answers

Answer:

My nettttttworkkkk is slowww

Concentration data is commonly monitored during a reaction to determine the order with respect to a reactant. Consider the types of observations listed, and determine which order is likely for that reactant. Assume all other factors are held constant. The reaction rate increases in direct proportion to the concentration of the reactant in solution.

a. The reaction rate is constant regardless of the amount of reactant in solution.
b. An increase in the concentration of the reactant in solution causes the reaction rate to increase exponentially.

Answers

Answer:

The reaction rate increases in direct proportion to the concentration of the reactant in solution - second order reaction

The reaction rate is constant regardless of the amount of reactant in solution - zero order reaction

An increase in the concentration of the reactant in solution causes the reaction rate to increase exponentially - first order reaction

Explanation:

In a second order reaction, the rate of reaction is directly proportional to the concentration of reactants. This implies that, reaction rate varies as the concentration of the reactant in solution varies.

For a zero order reaction, the rate of reaction is independent of the concentration of the reactants in solution. This means that reaction rate is constant regardless of the amount of reactant in solution.

For a first order reaction, the rate of reaction varies exponentially as the concentration of reactants. Hence, an increase or decrease in the concentration of the reactant in solution causes the reaction rate to increase or decrease exponentially.

When metal X is treated with sodium hydroxide, a white precipitate A is obtained which is soluble in excess NaOH to give a soluble complex B. Compound A is soluble in dilute HCl to form compound C. When the compound A is heated strongly it gives compound D which is used to extract metal. a) Identify X, A, B, C, D supporting your answer(s) with appropriate chemical reactions. b) At which group and period does X fall?​

Answers

Answer:

See explanation

Explanation:

If we look at the question closely, we will notice that the metal in question must be aluminum.

When aluminum is treated with sodium hydroxide, a precipitate, aluminium hydroxide is formed as follows;

Al(s) + 3NaOH(aq) ---> Al(OH)3(s) + 3Na(s)

In excess sodium hydroxide, the precipitate dissolves as follows;

Al(OH)3(s) + NaOH(aq) ----> [NaAlOH4]^-(aq)

The complex formed is sodium aluminum tetrahydroxo aluminate III.

The reaction of aluminum faith dilute hydrochloric acid occurs as follows to yield aluminum chloride;

2Al(s) + 6HCl(aq) ----> 2AlCl3(aq) + 3H2(g)

When aluminum metal is heated strongly, it yields aluminum oxide;

2Al(s) + 3O2(g) ---> Al2O3(s)

Potassium Chlorate decomposes according to the reaction below.

2KClO3(s)  2KCl(s) + 3O2(g)

A 4.35 g sample of KClO3 is heated and the O2 gas produced by the reaction is collected in an evacuated flask. What is the volume of the O2 gas if the pressure of the flask is 0.75 atm and the gas temperature is 27oC? R=0.0821 (L*atm)/(mol*K)

Answers

Answer:

1.75L

Explanation:

Reaction of decomposition is:

2KClO₃(s) →  2KCl(s) + 3O₂(g)

We determine moles of salt:

4.35 g . 1 mol /122.55 g = 0.0355 moles

Ratio is 2:3. 2 moles of salt can produce 3 moles of oxygen

Then, our 0.0355 moles of chlorate may produce (0.0355 . 3)/ 2 = 0.0532 moles.

We have determined, moles of gas and we have data of pressure and temperature. To find out the volume, we apply the Ideal Gases Law:

We convert T° from °C to K → 27°C + 273 = 300K

P . V = n . R . T

0.75 atm . V = 0.0532 mol . 0.0821 L.atm/mol.K . 300K

V = (0.0532 mol  . 0.0821 L.atm/mol.K . 300K) / 0.75 atm

V  = 1.75 Liters

A 0.15 M solution of BaCl2 contains: Group of answer choices 0.30 M Ba2 ions and 0.30 M Cl- ions. 0.15 M Ba2 ions and 0.15 M Cl- ions. 0.30 M Ba2 ions and 0.15 M Cl- ions. 0.15 M Ba2 ions and 0.30 M Cl- ions. none of the above

Answers

Answer:

0.15 M Ba⁺² ions and 0.30 M Cl⁻ ions

Explanation:

The dissociaton of barium chloride is as follows:

BaCl₂ → Ba²⁺ + 2Cl⁻

By observing the stoichiometric coefficients, we can tell that the number of moles of Ba²⁺ is the same as the number of moles of BaCl₂, while the number of moles of Cl⁻ is the double of that.

How many moles of CO2 exert a pressure of 2.34atm at a volume of 25.6L and a temperature of 305k?

Answers

Answer:

2.39 moles

Explanation:

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

Pressure (P) = 2.34 atm

Volume (V) = 25.6 L

Temperature (T) = 305 K

Number of mole (n) =?

NOTE: Gas constant (R) = 0.0821 atm.L/Kmol

The number of mole of CO₂ can be obtained by using the ideal gas equation as shown below:

PV = nRT

2.34 × 25.6 = n × 0.0821 × 305

59.904 = n × 25.0405

Divide both side by 25.0405

n = 59.904 / 25.0405

n = 2.39 moles

Thus, the number of mole of CO₂ is 2.39 moles.

Answer:

2.39

Explanation:

got it right on a quiz for credit recovery

Define solubility. a solid that does not dissolve in a gas the amount of a substance that will dissolve in a given amount of solvent the amount of a substance that will dissolve in a given amount of solute a liquid that does not dissolve in another liquid a solid mixed with another solid

Answers

Answer:

the amount of a substance that will dissolve in a given amount of solvent.

Explanation:

Solubility is a term used to describe how readily a substance can be dissolved in a solvent to form a solution. Thus, a substance is said to be soluble if it dissolves completely in a solvent and insoluble if it doesn't dissolve or only dissolves partially.

For example, sodium chloride (NaCl) when mixed with water dissociates into sodium and chloride ions. Thus, salt (sodium chloride) is said to be soluble because it dissolves completely in water.

Furthermore, a compound that dissolves completely in water to produce an aqueous solution is said to be soluble in water.

In conclusion, solubility is simply the amount of a substance such as salt, that will dissolve in a given amount of solvent. A solvent is any liquid such as water, coffee, tea, etc., that dissolves a liquid, gaseous, or solid solute to produce a solution.

2) If the density of chloroform is 1.48 g/mL, what is the volume of 541 g of chloroform?

Answers

Answer:

V = 365.54 mL

Explanation:

Given that,

The density of chloroform, d = 1.48 g/mL

The mass of chloroform, m = 541 g

We need to find the volume of chloroform.

We know that,

Density = mass/volume

So,

[tex]V=\dfrac{m}{d}\\\\V=\dfrac{541\ g}{1.48\ g/mL}\\\\=365.54\ mL[/tex]

So, the volume of chloroform is 365.54 mL.

Calculate the pressure exerted by 40 g of oxygen enclosed in a 1litre flask at 25°C. (0=16) (3 Marks) ​

Answers

Answer:

I don't know sorry siso

Explanation:

I don't know


Spell out the full name of the compound.
Submit
Help plz

Answers

Explanation:

A=Butan-2-one

B=Pentan-3-one

10-Concentration is the amount of a substance in a predefined volume of space. The basic measurement of concentration in chemistry is molarity or the number of moles of solute per liter of solvent. What is the molarity of a solution containing 9.478 grams of Rucl, in enough water to make 1.00 L of solution?

Answers

Answer:

0.0457 M

Explanation:

Concentration is the amount of a substance in a predefined volume of space. The basic measurement of concentration in chemistry is molarity or the number of moles of solute per liter of solution. What is the molarity of a solution containing 9.478 grams of RuCl₃, in enough water to make 1.00 L of solution?

Step 1: Given data

Mass of RuCl₃ (solute): 9.478 gVolume of solution: 1.00 L

Step 2: Calculate the moles corresponding to 9.478 g of RuCl₃

The molar mass of RuCl₃ is 207.4 g/mol.

9.478 g × 1 mol/207.4 g = 0.04570 mol

Step 3: Calculate the molarity of the solution

We will use the definition of molarity.

M = moles of solute / liters of solution

M = 0.04570 mol / 1.00 L = 0.0457 M

Match each term with the best description.

a. The electrode where oxidation occurs
b. A device that produces electricity
c. The connection between two half-cells
d. The electrode where reduction occurs
e. A device that consumes electricity
f. A device that utilizes redox reactions to either consume or produce electricity

1. Anode
2. Cathode
3. Electrolytic cell
4. Electrochemical
5. Galvanic cell
6. Salt bridge

Answers

Answer:

Match each term with the best description.

a. The electrode where oxidation occurs: Anode

b. A device that produces electricity: Galvanic cell

c. The connection between two half-cells: salt bridge

d. The electrode where reduction occurs: Cathode

e. A device that consumes electricity: Electrolytic cell

f. A device that utilizes redox reactions to either consume or produce electricity: Electrochemical cell.

Explanation:

a.The electrode where oxidation occurs is called the anode.

Oxidation is losing of electrons.

b. Galvanic cell produces electricity by using redox chemical reaction.

It is also called a voltaic cell or electrochemical cell.

c. The connection between two cells is called a salt bridge.

It will not allow the solutions to diffuse with each other.

It maintains electrical neutrality.

d. The electrode where reduction occurs: Cathode

Reduction means the gaining of electrons.

e. Electrolytic cell is the one that consumes electricity and then produces a chemical change.

f. A device that utilizes redox reactions to either consume or produce electricity: Electrochemical cell.

what is the theoretical yield of Mg(s) + O2(g) → MgO(s)

will give brainliest fakes will be reported

Answers

The anwser for this question is on socractic don’t report me for trying to help :((( !!

What are the main modifications of John Dalton's atomic theory

Answers

MODIFICATION of DALTON's ATOMIC THEORY: 1. Matter is made up of small indivisible particles called atoms: Atoms can, however, no longer be regarded as indivisible because according to Rutherford's discovery, atom is made up of three main subatomic particles called PROTONS, NEUTRONS AND ELECTRONS. 2.

Calculate the energy in kj/mol of photon in red light of wavelength 656nm​

Answers

Answer:

you don't know the answer?ha me too

To prepare a sample in a capillary tube for a melting point determination, gently tap the tube into the sample with the ___________ end of the tube down. Continue tapping until the sample. _____________ Then, with the __________ end of the tube down, tap the sample down slowly or __________ to move the sample down faster. Finally, make sure that you can see ___________ in the magnifier when placed in the melting point apparatus before turning on the heat.

Answers

Answer: Hello I was able to find the missing options related to your question online but I couldn't attach them hence I just used them to provide the relevant solution

answer:

Open Is a couple of millimeters highclosed Drop tube into a longer tube sample clearly

Explanation:

OPEN end of the tube down. Continue tapping until the sample. Is a couple of mm high Then, with the Closed end of the tube down, tap the sample down slowly or drop tube into a longer/larger tube to move the sample down faster. Finally, make sure that you can see  sample clearly in the magnifier when placed in the melting point apparatus before turning on the heat.

An article about half-lives describes a parent isotope. What is a parent isotope?

A. The isotope that forms from the radioactive decay of a less stable isotope.
B. The isotope that forms from the radioactive decay of a more stable isotope.
C. The isotope that undergoes radioactive decay to form a less stable isotope.
D. The isotope that undergoes radioactive decay to form a more stable isotope.

I think the answer is D.

Answers

Answer:

D. The isotope that undergoes radioactive decay to form a more stable isotope.

Explanation:

In radioactivity, isotopes of an unstable atom disintegrates/decays into more stable ones accompanied with the emissions of certain particles e.g alpha, gamma and beta particles.

In this process, the isotope of the atom that undergoes radioactive decay to form a more stable isotope is known as the PARENT ISOTOPE while the more stable isotope that arises from the decay is called the DAUGHTER ISOTOPE.

(238, 92) Uranium → (234,90) Thorium + (4,2) Helium

In the above reaction, Uranium is the parent isotope because it decays into a more stable isotope (Thorium).

Answer:

He's Right

Explanation:

i got it right

Which of the following is NOT true about soil? *

Answers

There is one kinds of soil in the United States

g What happens to the intensity of the solution's color as the concentration of the solute changes? The intensity of the color directly changes in response to the concentration. The intensity of the color inversely changes in response to the concentration. The intensity of the color always increases in response to any concentration change. The intensity of the color always decreases in response to any concentration change. The intensity of the color does not change in response to any concentration change.

Answers

Answer:

The intensity of the color directly changes in response to the concentration

Explanation:

One of the major indicators of the concentration of a solution is the colour of the solution.

The colour of the solution changes as the concentration of the solution changes. If the solution becomes more concentrated, the colour of the solution becomes deeper. If the solution becomes more dilute, the colour of the solution becomes lighter.

It then follows that, the intensity of the color of a solution directly changes in response to the concentration of the solution.

Chemistry Grade 11: Hi, I don't know what this is, please help?
CALCULATING % YIELD STEPS:
1.
2.
3.
4.

Answers

so percent yield is actual yield/theoretical times 100. actual yield is the number a chemical produces. theoretical yield is what it should produce

Answer:

1. Write the balanced chemical equation for the reaction

2. Identify all important information provided in the word problems or data table.

3. Solve for the theoretical yield of the reaction, following all the steps of a stoichiometry calculation organizer. Use two calculations if both reactants are provided.

4. Use the percent yield equation to calculate the percent yield of the reaction.

Explanation:

its comes right from the 5.06 lesson

Sodium azide, NaN3, the explosive compound found in automobile air bags, decomposes according to the following equation: 2NaN3(s)right arrow 2Na(s) + 3N2(g)
What mass of NaN3 is required to provide the nitrogen needed to inflate an 80.0-L bag to a pressure of 1.3 atm at 27 degree C? What is the density of the gas under these conditions?

Answers

Answer:

1.9 × 10² g NaN₃

1.5 g/L

Explanation:

Step 1: Write the balanced decomposition equation

2 NaN₃(s) ⇒ 2 Na(s) + 3 N₂(g)

Step 2: Calculate the moles of N₂ formed

N₂ occupies a 80.0 L bag at 1.3 atm and 27 °C (300 K). We will calculate the moles of N₂ using the ideal gas equation.

P × V = n × R × T

n = P × V / R × T

n = 1.3 atm × 80.0 L / (0.0821 atm.L/mol.K) × 300 K = 4.2 mol

We can also calculate the mass of nitrogen using the molar mass (M) 28.01 g/mol.

4.2 mol × 28.01 g/mol = 1.2 × 10² g

Step 3: Calculate the mass of NaN₃ needed to form 1.2 × 10² g of N₂

The mass ratio of NaN₃ to N₂ is 130.02:84.03.

1.2 × 10² g N₂ × 130.02 g NaN₃/84.03 g N₂ = 1.9 × 10² g NaN₃

Step 4: Calculate the density of N₂

We will use the following expression.

ρ = P × M / R × T

ρ = 1.3 atm × 28.01 g/mol / (0.0821 atm.L/mol.K) × 300 K = 1.5 g/L

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