Which equation should you use to find the final
concentration?

Answer:

1.5 litre of C5H12 produce 9 litre of water vapour;

Explanation:

First balance the combustion reaction;

[tex]C_5H_12 +8O_2[/tex] → [tex]5CO_2 +6H_2O[/tex]

from the balance reacion it is clearly that,

one mole of C5H12 reacts completely with 8 mole of O2 gas;

Hence

one litre of C5H12 reacts completely with 8 litre of O2 gas;

there fore 1.5 litre C5H12 needs 12 litre oxygen gas but we have 15 litre.

so,

C5H12 is a limiing reactant and O2 is a excess reactant.

so quantity of H2O depends on limiting reactant;

one litre of C5H12 produce 6 litre of water vapour;

therefore,

1.5 litre of C5H12 produce 9 litre of water vapour;

Answer:

94.8% is the percentage yield of this reaction.

Explanation:

Mass of aluminium = 3.8 g

Moles of aluminium = [tex]\frac{3.8 g}{27 g/mol}=0.1407 mol[/tex]

[tex]2Al+3Cl_2\rightarrow 2AlCl_3[/tex]

According to reaction, 2 moles of aluminum gives 2 moles of aluminium chloride, then 0.1407 moles of aluminium will give:

[tex]\frac{2}{2}\times 0.1407 mol=0.01407 mol[/tex] aluminium chloride

Mass of 0.1407 moles of aluminum chloride:

= 0.1407 mol × 133.5 g/mol = 18.78 g

Theoretical yield of aluminum chloride = 18.78 g

Experimental yield of aluminum chloride = 17.8 g

The percentage yield of reaction:

[tex]=\frac{\text{Experimental yield}}{\text{Theoretical yield}}\times 100[/tex]

[tex]=\frac{17.8 g}{18.78 g}\times 100=94.8\%[/tex]

94.8% is the percentage yield of this reaction.

Answer:

The answer is 1.5 moles.

Explanation:

An ideal gas is a theoretical gas that is considered to be composed of point particles that move randomly and do not interact with each other. Gases in general are ideal when they are at high temperatures and low pressures.

An ideal gas is characterized by three state variables: absolute pressure (P), volume (V), and absolute temperature (T). The relationship between them constitutes the ideal gas law:

P * V = n * R * T

where n is the number of moles and R is the molar constant of the gases.

In this case:

Replacing:

1 atm*33.6 L= n* 0.082 [tex]\frac{atm*L}{mol K}[/tex] *273 °K

Solving:

[tex]n=\frac{1 atm* 33.6 L}{0.082\frac{atm*L}{mol K}*273K }[/tex]

n= 1.5 moles

So, the answer is 1.5 moles.

Answer:

1.5 moles

Explanation:

Answer:

It's the middle one, B. H+ and OH-

Explanation:

I just did the question online

Answer : The limiting reagent in this reaction is, [tex]Al_2(SO_4)_3[/tex] and number of moles of excess reagent is, 1.69 moles

Explanation : Given,

Mass of [tex]Al_2(SO_4)_3[/tex] = 500.0 g

Mass of [tex]Ca(OH)_2[/tex] = 450.0 g

Molar mass of [tex]Al_2(SO_4)_3[/tex] = 342.15 g/mol

Molar mass of [tex]Ca(OH)_2[/tex] = 74.1 g/mol

First we have to calculate the moles of [tex]Al_2(SO_4)_3[/tex] and [tex]Ca(OH)_2[/tex].

[tex]\text{Moles of }Al_2(SO_4)_3=\frac{\text{Given mass }Al_2(SO_4)_3}{\text{Molar mass }Al_2(SO_4)_3}[/tex]

[tex]\text{Moles of }Al_2(SO_4)_3=\frac{500.0g}{342.15g/mol}=1.461mol[/tex]

and,

[tex]\text{Moles of }Ca(OH)_2=\frac{\text{Given mass }Ca(OH)_2}{\text{Molar mass }Ca(OH)_2}[/tex]

[tex]\text{Moles of }Ca(OH)_2=\frac{450.0g}{74.1g/mol}=6.073mol[/tex]

Now we have to calculate the limiting and excess reagent.

The given chemical reaction is:

[tex]Al_2(SO_4)_3(aq)+3Ca(OH)_2(aq)\rightarrow 2Al(OH)_3(s)+3CaSO_4(s)[/tex]

From the balanced reaction we conclude that

As, 1 mole of [tex]Al_2(SO_4)_3[/tex] react with 3 mole of [tex]Ca(OH)_2[/tex]

So, 1.461 moles of [tex]Al_2(SO_4)_3[/tex] react with [tex]1.461\times 3=4.383[/tex] moles of [tex]Ca(OH)_2[/tex]

From this we conclude that, [tex]Ca(OH)_2[/tex] is an excess reagent because the given moles are greater than the required moles and [tex]Al_2(SO_4)_3[/tex] is a limiting reagent and it limits the formation of product.

Number of moles of excess reagent = 6.073 - 4.383 = 1.69 moles

Therefore, the limiting reagent in this reaction is, [tex]Al_2(SO_4)_3[/tex] and number of moles of excess reagent is, 1.69 moles

Answer:

Ecological Relationships are of two types - Oppositional Relationships and Symbiotic Relationships. Oppositional Relationships are of two types - Predation and Competititon. Symbiotic Relationships are of four types - Mutualism, Commensalism, Amensalism & Parasitism.

Explanation:

Answer:

15.33

Explanation:

Given parameters:

Mass of KOH = 121g

Volume of solution  = 100mL   = 0.1dm³

Molar mass of KOH  = 56.11g/mol

Unknown:

pH  of the solution = ?

Solution:

To find the pH, we must first know the concentration of the solution obtained by mixing KOH up to this volume.

This can be done by finding the molarity of the solution.

  Molarity  = [tex]\frac{number of moles }{volume of solution}[/tex]

  Number of moles of KOH  = [tex]\frac{mass}{molar mass}[/tex]    = [tex]\frac{121}{56.11}[/tex]   = 2.16mole

Input parameters;

 Molarity of solution = [tex]\frac{2.16}{0.1}[/tex]   = 21.6moldm⁻³

       KOH    →    OH⁻   +          K⁺

       21.6           21.6              21.6

In the solution we have 21.6moldm⁻³ of OH⁻ which is need to find the pH;

          pOH  = -log₁₀(OH⁻)

         pOH  =  -log₁₀21.6

          pOH  = -1.33

Since pH + pOH   = 14

          pH  = 14 - (-1.33)  = 15.33

Answer:

[tex]H_{rxn} = -93.52 \frac{KJ}{mol}[/tex]

The final temperature [tex]T_{2} = 50.21[/tex]  ° c

Explanation:

(a).

[tex]H_{rxn} = H_{products} - H_{reactents}[/tex]

[tex]H_{reactants}[/tex] = - 813.9 [tex]\frac{KJ}{mol}[/tex]

[tex]H_{Products}[/tex] = - 907.51  [tex]\frac{KJ}{mol}[/tex]

[tex]H_{rxn} = -907.51 + 813.9[/tex]

[tex]H_{rxn} = -93.52 \frac{KJ}{mol}[/tex]

(b).

[tex]H_{rxn} = -93.52 \frac{KJ}{mol}[/tex]

E = 93520 J

C = 3.5 [tex]\frac{KJ}{kg K}[/tex]

Initial temperature [tex]T_{1} = 25[/tex] ° c

Mass (m) = density × volume

m = 1060 × 1

m = 1060 gm

[tex]E = m C (T_{2} - T_{1} )[/tex]

93520 =1060 × 3.5 × ( [tex]T_{2}[/tex] - 298 )

[tex]T_{2} = 50.21[/tex]  ° c

This is the final temperature.

(c).

The density of sulfuric acid is more than the water. so when water is added to acid the mixing process does not takes properly. So we have to add acid in to the water.

Adding water is exothermic process so when we add water to acid than in that case more energy produces and wasted.

3.41 is  the pH value of a sample that has ten times fewer hydronium ions than an equal volume of a vinegar sample with a pH value of 2.4.

Explanation:

pH of the first sample of acetic acid = 2.4

to know the [H+] concentration in the acetic acid solution, the equation used is:

pH = -log [H+]

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

[H+] = [tex]10^{-2.4}[/tex]

[H+]  = 3.98 X [tex]10^{-3}[/tex] M

The concentration of H+ ion in first case is 3.98 X [tex]10^{-3}[/tex] M, the second sample has ten times less hydronium ion so concentration of first case is divided by 10.

3.98 x [tex]10^{-4}[/tex] M

Now pH of the sample having 10 times fewer ions of acetic acid:

pH = -log [H+]

putting the values in the above equation:

pH = -log [3.98 x [tex]10^{-4}[/tex] M]

pH = 3.41

If solution has ten times less hydronium ion the pH will change to 3.41.

3.41 is the pH value of a sample that has ten times fewer hydronium ions. pH gives the concentration of Hydronium ion.

What information we have:

pH of the first sample of acetic acid = 2.4

To know the [H+] concentration in the acetic acid solution, the equation used is:

[tex]pH = -log [H^+]\\\\H^+ = 10^{-pH}\\\\H^+ = 10^{-2.4}\\\\H^+ = 3.98 *10^{-4} M[/tex]

The concentration of H+ ion in first case is [tex]3.98 *10^{-4} M[/tex], the second sample has ten times less hydronium ion so the concentration of first case is divided by 10.

[tex]3.98 *10^{-4} M[/tex],

Now pH of the sample having 10 times fewer ions of acetic acid:

pH = -log [H+]

pH = -log [ [tex]3.98 *10^{-4} M[/tex],]

pH = 3.41

If the solution has ten times less hydronium ion the pH will change to 3.41.

Find more information about pH here:

brainly.com/question/13557815

Answer:

0.33 moles of Oxygen at stp would occupy a volume of 7.392 dm³

Explanation:

1 mole of every gas at standard temperature and pressure (stp) occupies 22.4 dm³

0.33 moles of Oxygen at stp would occupy a volume of 0.33 × 22.4 dm³ = 7.392 dm³

Hope this Helps!!!

Answer:

[tex]V = 7.391\,L[/tex]

Explanation:

Let suppose that oxygen behaves ideally. The equation of state of the ideal gas is:

[tex]P\cdot V = n\cdot R_{u}\cdot T[/tex]

The volume is now cleared:

[tex]V = \frac{n\cdot R_{u}\cdot T}{P}[/tex]

[tex]V = \frac{(0.33\,mol)\cdot \left(0.082\,\frac{atm\cdot L}{mol\cdot K} \right)\cdot (273.15\,K)}{1\,atm}[/tex]

[tex]V = 7.391\,L[/tex]

Answer:

Temperature of gas: 3 °C Height of the column of gas: 5.7 cm Temperature of gas: 276k Volume of gas: .72 cm^3

Explanation:

edge 2021

The value of  Temperature is 276K

and of Volume is 0.71592 [tex]cm^{3}[/tex]

As per the formula of conversion of degree Celsius to kelvin temperature

1°C=273K

∴23 °c +273= 276 K

V=π[tex]r^{2}[/tex]h

V= volume

r = radius of capillary tube =0.2 cm

h=height of column=5.7 cm

∴V=3.14×[tex](0.2)^{2}[/tex]×5.7

∴V=0.71592[tex]cm^{3}[/tex]

Hence, the value of temperature and volume are 276K and 0.71592[tex]cm^{3}[/tex], respectively.

Learn more about temperature calculation here

https://brainly.com/question/275961

#SPJ2

Answer:

0.81M

Explanation:

Molarity, M = number of moles, n / Volume, V

number of moles of HCl, n=

mass of HCl / molar mass of HCl

Mass of HCl = 13.3g

Molar mass of HCl = 1 + 35.5 = 36.5g/mol

n = 13.3/36.5=0.364mol

V = 447mL=447/1000 L = 0.447L

Note that M is mol/L, hence, we convert 447mL to L. 1 mL = 1/1000 L

M=0.364mol/0.447L

M= 0.81M

Therefore, the molarity of the HCl solution is 0.81M

Answer:

500.65mL

Explanation:

The following information were obtained from the question:

V1 (initial volume) = 461 mL

P1 (initial pressure) = stp = 101325Pa

P2 (final pressure) = 93.3 kPa

Recall: 1KPa = 1000Pa

Therefore, 93.3 kPa = 93.3x1000 = 93300Pa

V2 (final volume) =?

Using the Boyle's law equation P1V1 = P2V2, the final volume of the gas can be obtained as follow:

P1V1 = P2V2

461 x 101325 = 93300 x V2

Divide both side by 93300

V2 = (461 x 101325)/93300

V2 = 500.65mL

Therefore, the volume of Neon at 93.3 kPa is 500.65mL

Answer:

The amount of water in a 95 mL sample of the solution is 33.25 mL

Explanation:

65% (v/v) rubbing alcohol is a solution containing 65 mL rubbing alcohol in 100 mL solution of the rubbing alcohol and water

Therefore, 95 mL sample of the solution will contain x mL of rubbing alcohol;

x = 65% × 95 =  0.65 × 95 = 61.75 mL rubbing alcohol and therefore, the amount of water contained = 95 - 61.75 = 33.25 mL

The amount of water in a 95 mL sample of the solution = 33.25 mL.

The volume of water present in 95 ml of 65 % rubbing alcohol solution has been 33.25 ml.

The v/v has been the concentration representation of the volume of solute present in the total volume of the solution.

The given aqueous solution has 65 % v/v concentration of the rubbing alcohol. This states that there has been a presence of 65 ml of rubbing alcohol in 100 ml of the solution.

Since, in 100 ml sample there has been a presence of 65ml alcohol. The volume of water in 100 ml sample has been the remaining portion of the solution.

[tex]\rm Volume \;of \;water \;= \;Total \;volume - volume \;of \;alcohol\\Volume \;of\; water = 100 \;ml - 65 \;ml\\Volume \;of \;water = 35 \;ml[/tex]

The aqueous solution of rubbing alcohol has been consisted of 35 ml water per 100 ml solution.

Since, 100 ml solution = 35 ml water

[tex]\rm 95\;ml\;solution\;=\;\dfrac{35}{100}\;\times\;95\;ml\;water\\95\;ml\;solution=33.25\;ml\;water[/tex]

The volume of water present in 95 ml of 65 % rubbing alcohol solution has been 33.25 ml.

For more information about the v/v ratio, refer to the link:

https://brainly.com/question/1578538

The standard potential for a galvanic cell consisting of nickel and copper electrodes at 25 °C is calculated using the standard reduction potentials for each electrode, resulting in a cell potential of +0.77 V.

To calculate the standard potential for the galvanic cell at 25 °C, you need to know the standard reduction potentials for the nickel and copper electrodes. These potentials can be found in a table of standard reduction potentials. The cell potential (Ecell) is the difference between the reduction potential of the cathode and the anode.

In our case, for a cell composed of nickel and copper electrodes, the standard reduction potential for the nickel(II) ion to nickel reaction is approximately -0.25 V, and for the copper(I) ion to copper reaction, it is +0.52 V.

Considering that the copper electrode undergoes reduction (acts as cathode) and the nickel electrode undergoes oxidation (acts as anode), we use the following formula:

[tex]E_{cell} = E_{cathode} - E_{anode[/tex]

Therefore: Ecell = (+0.52 V) - (-0.25 V) = +0.52 V + 0.25 V = +0.77 V

The standard potential for this galvanic cell at 25 °C is +0.77 V.

Answer: All of them are right there’s no wrong answer

Explanation:

Masses for the metal and the water in the calorimeter, temperature changes for the water and the metal, and the known specific heat of the water.

First, the masses of both the metal and the water within the calorimeter are crucial, as they determine the amount of substance undergoing the temperature change. Second, the temperature changes (Tw, final​ −Tw, initial​  and T metal, final −T metal, initial​ ) are necessary to quantify the heat exchange during the experiment. Lastly, the known specific heat of water (C water​ ) plays a role in the calculation, as it is a fundamental constant representing the amount of heat needed to raise the temperature of water.

The first law of thermodynamics, which states that the heat lost by the metal equals the heat gained by the water, and the ability of heat to flow from a hot object to a cooler one are overarching principles guiding the experimental setup and the interpretation of results. However, these principles are not directly inputted into the formula but are fundamental concepts in calorimetry and thermodynamics that inform the experimental design and the interpretation of the calculated specific heat values.

For more questions on specific heat

https://brainly.com/question/27991746

#SPJ3

Answer:

Fatty acids have an even number of carbons because they are synthesized from a starting material (acetyl-CoACoA) that has an even number of carbons.

Explanation:

Fatty acids are carboxylic acids and are known to have even number of carbon atoms because they are synthesized from a 2 carbon atom acetyl Co-A molecules which are assembled together. It contains a carboxylate group covalently joined with an hydrophobic head of CH3-(CH2)n and may have an unsatireated CH=CH group within its CH2 chain. The synthesis of fatty acids from acetyly Co-A involves the activation reaction of an enzyme acetyl Co-A synthetase with an acid. It involves dehydrogebation, hydration, oxidation and thiolysis. Fatty acids vary in length of its chain, the number of carbon-carbon double bonds attached to its CH2 chain nd also the location of those double bonds in the carbon chain. Saturated fatty acids are those without carbon-carbon double bond in its chain while unsaturated have carbon- carbon double bonds. Monounsaturated fatty acids have one carbon-carbon double bonds and polyunsaturated fatty acids have two or more carbon-carbon double bonds.

Fatty acids are the building blocks of fat molecules. The fat when broken down into simpler forms, yields fatty acids and glycerol.

The correct answer is:

Option C. Fatty acids have an even number of carbons because they are synthesized from a starting material (acetyl-CoACoA) that has an even number of carbons.

The fatty acids are generally even numbers because of the even precursor.

The metabolism of fatty acids starts with the two molecules of the acetyl coenzyme A, which on assembling yields the even-numbered of fatty acids.

The acetyl coenzyme A is an even-numbered two-carbon molecule, which undergoes enzyme-catalyzed reactions to yield an even number of fatty acids.

The even number of fatty acids can be saturated (made up of single bonds) or can be unsaturated (presence of double or triple bonds).

Therefore, Option C is correct.

To know more about fatty acids, refer to the following link:

https://brainly.com/question/13528495

The final temperature of the gas is 234K. As the volume of the increases to the given value, the temperature of the gas also increases.

Charle's law states that the volume of an ideal gas is directly proportional to the absolute temperature provided pressure is kept at constant.

It is expressed as;

V₁/T₁ = V₂/T₂

Given the data in the question;

Initial volume V₁ = 62.0mL = 0.062L

Initial temperature T₁ = 175K

Final volume V₂ = 82.9mL = 0.0829L

Final temperature T₂ = ?

To calculate the final temperature, we subtsitute our given values into the expression above.

V₁/T₁ = V₂/T₂

V₁T₂ = V₂T₁

T₂ = V₂T₁ / V₁

T₂ = ( 0.0829L × 175K ) / 0.062L

T₂ = 14.5075LK / 0.062L

T₂ = 234K

The final temperature of the gas is 234K. As the volume of the increases to the given value, the temperature of the gas also increases.

Learn more about Charle's law here: brainly.com/question/21184611

#SPJ2

Answer:

The specific heat of alloy  [tex]C_{alloy} = 1.007 \frac{KJ}{Kg K}[/tex]

Explanation:

Mass of the alloy = 30.5 gm = 0.0305 kg

Initial temperature = 93 °c = 366 K

Mass of water = 50 gm = 0.05 kg

Initial temperature = 22 °c = 295 K

Final temperature of the mixture = 31.1 °c = 304.1 K

From the energy conservation principal the heat lost by the alloy is equal to heat gain by the water.

Heat lost by alloy

[tex]Q_{alloy} = m C (T_{f}- T_{i} )[/tex]

[tex]Q_{alloy} = (0.0305) C_{alloy} (366-304.1)[/tex]

[tex]Q_{alloy} = (1.88795) C_{alloy}[/tex]  ------- (1)

Heat gain by water

[tex]Q_{w} = (0.05) (4.18) (304.1 - 295)[/tex]

[tex]Q_{w} = 1.9019 \frac{KJ}{kg K}[/tex]  ------- (2)

Equation (1) = Equation (2)

[tex](1.88795) C_{alloy} = 1.9019[/tex]

[tex]C_{alloy} = 1.007 \frac{KJ}{Kg K}[/tex]

This is the specific heat of alloy.

Taking into account the definition of calorimetry,  the specific heat capacity of the alloy is 1.063 [tex]\frac{kJ }{kgK}[/tex]

In first place, calorimetry is the measurement and calculation of the amounts of heat exchanged by a body or a system.

In this way, between heat and temperature there is a direct proportional relationship.

The constant of proportionality depends on the substance that constitutes the body and its mass, and is the product of the specific heat by the mass of the body.

So, the equation that allows to calculate heat exchanges is:

Q = C× m× ΔT

where Q is the heat exchanged by a body of mass m, made up of a specific heat substance C and where ΔT is the temperature variation.

In this case, you know:

for alloy:

for water:

Replacing in the expression to calculate heat exchanges:

for alloy:

for water:

On the other hand, the heat of the calorimeter can be expressed as:

Qcalorimeter= Ccalorimeter×ΔT

Being:

and replacing you get:

Qcalorimeter= 0.0092 [tex]\frac{kJ}{K}[/tex]× 9.2 K

It should be taken into account that a system at different temperatures evolves spontaneously towards a state of equilibrium in which all bodies have the same temperature. Then, mixing two quantities of liquids at different temperatures generates an energy transfer in the form of heat from the hottest to the coldest. Said energy transit is  held until temperatures equalize, when it is said to have reached thermal equilibrium.

So the heat released by the sample is absorbed by the calorimeter and the water.

Qalloy= Qcalorimeter + Qwater

Replacing the corresponding expressions and solving:

Calloy× 0.0305 kg× 61.9 K= 0.0092 [tex]\frac{kJ}{K}[/tex]× 9.2 K + 4.18 [tex]\frac{kJ}{kgK}[/tex]× 0.050 kg× 9.2 K

Calloy× 1.88795 kg× K= 0.08464 kJ + 1.9228 kJ

Calloy× 1.88795 kg× K= 2.00744 kJ

[tex]Calloy=\frac{2.00744 kJ }{1.88795 kgK}[/tex]

Calloy= 1.063 [tex]\frac{kJ }{kgK}[/tex]

Finally, the specific heat capacity of the alloy is 1.063

Learn more:

Most nonmetals do not lose electrons when bonding with metal atoms; instead, they tend to gain electrons, forming anions. They share electrons in covalent bonds with other nonmetals.

The characteristic that is not typical of most nonmetals is their atoms lose electrons when bonding with metal atoms. When bonding occurs, nonmetals usually do the opposite; they tend to gain electrons to achieve more stable electron configurations. This is often seen in ionic bonds, where metals lose electrons to become positively charged cations, and nonmetals gain electrons to become negatively charged anions. However, in the case of bonding with other nonmetals, they typically share electrons, resulting in covalent bonds. Furthermore, nonmetals do indeed readily form compounds with other elements, either through ionic or covalent bonding.

Final answer:

Most nonmetals gain electrons when bonding with metal atoms to achieve stability, and they can also share electrons with other nonmetal atoms.

Explanation:

The characteristic that is not a characteristic of most nonmetals is that their atoms lose electrons when bonding with metal atoms. Nonmetals tend to gain electrons when bonding with metal atoms in order to achieve a stable electron configuration. They can also share electrons with other nonmetal atoms to form covalent bonds. Additionally, nonmetals readily form compounds with other elements.

Answer:

0.925 mole

Explanation:

From the question given, the following were obtained:

Volume = 1.0L

Molarity = 0.925 M

Number of mole of Nickel (II) chloride =?

Molarity is simply defined as the mole of solute per unit litre of the solution.

It is represented mathematically as:

Molarity = mole /Volume

With the above equation, we can easily find the mole of Nickel (II) chloride present in the solution as follow:

Molarity = mole /Volume

0.925 = mole / 1

Mole = 0.925 x 1

Mole of Nickel (II) chloride = 0.925 mole

Answer:

P₃ = 594.1 mmHg

Explanation:

Given data:

Total pressure of container = 1439 mmHg

Partial pressure of 1st gas = 523.3 mmHg

Partial pressure of 2nd gas = 509.8 mmHg

Partial pressure of 3rd gas = ?

Solution:

According to Dalton law of partial pressure,

The total pressure inside container is equal to the sum of partial pressures of individual gases present in container.

Mathematical expression:

P(total) = P₁ + P₂ + P₃+ ............+Pₙ

Now we will solve this  problem by using this law.

P(total) = P₁ + P₂ + P₃

439 mmHg =  523.3 mmHg +  509.8 mmHg + P₃

439 mmHg =  1033.1 mmHg + P₃

P₃ = 1033.1 mmHg -439 mmHg

P₃ = 594.1 mmHg

The term associated with the solution is saturated.

The term associated with a solution that is saturated at 25°C and then slowly cooled to 20°C with no change to its appearance is saturated.

https://brainly.com/question/18482334

#SPJ11

Answer:

81mmHg

Explanation:

Since the total pressure is 2700mmHg and we are told that nitrogen occupies 3% of that pressure in the Venus atmosphere. We have to find the pressure of nitrogen using its percentage.

It should be noted that the total pressure of the atmosphere is the sum total of the partial pressures of all the respective gases in the atmosphere.

Hence partial pressure of nitrogen= 3.0%× 2700mmHg= 3.0/100× 2700

Partial pressure of nitrogen= 81mmHg

Answer:

All these statements are true.

Explanation:

Many describe it as an "educated guess," based on prior knowledge and observation. While this is true, the definition can be expanded. A hypothesis also includes an explanation of why the guess may be correct.

hope this helps :)

The true statement about hypothesis is: All these statements are true. The option (4) is correct.

A hypothesis is a testable statement that is formulated based on observations and background research.

It is typically written in an "if... then" form, which clearly states the relationship between two variables: the independent variable (the one at that the researcher manipulates) and the dependent variable (the one that the researcher measures).

A well-constructed hypothesis will also include a prediction regarding the dependent variable, which is an educated guess about the outcome of the experiment or study. Therefore, all the given statements about a hypothesis are true.

1. "It is written in an 'if...then' format." - This is true because a hypothesis often takes the form of ""If [independent variable], then [dependent variable]"" to clearly indicate the cause-and-effect relationship being tested.

2. "It is an educated guess based on background research." - This is true because a hypothesis is not just a random guess; it is formulated after conducting a thorough literature review and observing patterns or phenomena that suggest a certain relationship or outcome.

3. "It includes a prediction regarding the dependent variable." - This is true because a hypothesis predicts the effect that changing the independent variable will have on the dependent variable.

Since all three statements accurately describe the characteristics of a hypothesis, the correct answer is that all these statements are true.

The complete question is:

Which statement about a hypothesis is true?

1) It is written in an “if…then” format.

2) It is an educated guess based on background research.

3) It includes a prediction regarding the dependent variable.

4) All these statements are true.

Answer:

OK, I don't know if this is right but this is my thinking of it. I hope this helps you out.

Let's do problem "a"

Step 1.  Write a balanced equation.

                                       2 HCl  +  Ba(OH)2  -------------->  BaCl2  + 2 HOH  

Step 2.  Underneath the HCl and Ba(OH)2 in the equation write what you are given and what you need to find out.

                                    2 HCl        +       Ba(OH)2  -------------->  BaCl2  + 2 HOH

                                 C = 0.130 mol/L    v = 56 mL

                                  V = ?                   C = 0.109 mol/L

Step 3.  They ALWAYS provide a way to calculate the number of moles of one of the substances.  In this case it is Ba(OH)2 because you have C and V

                         n = C X V            n = 0.109 x 56 = 6.104 millimoles

Step 4.  Use the equation to figure out how many moles of the unknown (HCl) you will need.

               the equation says you need TWICE as many moles as you have of Ba(OH)2.  So you will need 6.104 millimoles x 2 or 12.208 milimoles.

Step 5.  Now that yo have moles and concentration of HCl you can now calculate volume

                  C = n / V, so V = n / C

                                 12.208 millimoles / 0.130 mol/L = 93.9 mL

Use this method for all these kind of problems.  

In B) you will have to convert he g of NaOH into moles by 0.240 / 40.00 g/mol and then following trhe rest of the procedure.

C) is done the same way.  convert the g of Na2SO4 into moles first.

d) is almost the same as a) except this time when you find the moles of Ca(OH)2 you just have to convert the moles into mass by multiplying moles x Molar mass of Ca(OH)2.

Best of luck.

Explanation:

To neutralize 15 mL of 2.0 M Ba(OH)₂, one would need 60 mL of 1.0 M HCl. The calculation is based on the mole ratio from the balanced chemical equation, with the final step being the conversion from liters to milliliters.

To determine how many milliliters of 1.0 M HCl are needed to neutralize 15 milliliters of 2.0 M Ba(OH)₂, you need to use the concept of mole ratios from the balanced chemical equation. The reaction between hydrochloric acid (HCl) and barium hydroxide (Ba(OH)₂) is:

2 HCl + Ba(OH)₂ ightarrow BaCl2 + 2 H₂O

The balanced equation shows that two moles of HCl react with one mole of Ba(OH)2. First, calculate the moles of Ba(OH)2:

moles Ba(OH)2 = volume (L) times molarity (M) = 0.015 L times 2.0 M = 0.03 moles

Since the ratio of HCl to Ba(OH)₂ is 2:1, you will need twice as many moles of HCl to neutralize Ba(OH)₂. Therefore, you'll need:

moles HCl needed = 0.03 moles Ba(OH)₂ times 2 = 0.06 moles HCl

Now, convert moles of HCl to volume:

volume HCl (L) = moles HCl / molarity HCl = 0.06 moles / 1.0 M = 0.06 L

Finally, convert liters to milliliters:

volume HCl (mL) = volume HCl (L) times 1000 mL/L = 0.06 L times 1000 mL/L = 60 mL

Therefore, 60 mL of 1.0 M HCl are needed to exactly neutralize 15 mL of 2.0 M Ba(OH)₂.

Answer:

The energy absorbed when 6.20 grams of aluminum is heated from 10.0°C to 65.0°C is 306.9 Joules.

Explanation:

[tex]Q=mc\Delta T=mc\times (T_2-T_1)[/tex]

Where:

Q = heat absorbed  or heat lost

c = specific heat of substance

m = Mass of the substance

ΔT = change in temperature of the substance

[tex]T_1,T_2[/tex] : Initial and final temperature of the substance

We have mass of aluminium = m = 6.20 g

Specific heat of aluminium= c = 0.900 J/g°C

Initial and final temperature of the aluminium [tex]T_1=10.0^oC [/tex]

Final temperature of the aluminium = [tex]T_2=65.0^oC[/tex]

Heat absorbed by the aluminium:

[tex]Q=6.20 g\times 0.900J/g^oC\times (65.0^oC-10.0^oC)=306.9 J[/tex]

The energy absorbed when 6.20 grams of aluminum is heated from 10.0°C to 65.0°C is 306.9 Joules.

Answer:

ΔHr = -275 kj

Explanation:

It is possible to obtain the net change in enthalpy for the formation of one mole of lead(II) sulfate from lead, lead(IV) oxide, and sulfuric acid using the reactions:

(1) H₂SO₄(l) → SO₃(g) + H₂O (l) ΔH=+113kJ

(2) Pb(s) + PbO₂(s) + 2SO₃(g) → 2PbSO₄(s) ΔH=−775kJ

If you sum (1) + ¹/₂(2) you will obtain:

H₂SO₄(l) + ¹/₂Pb(s) + ¹/₂PbO₂(s) → PbSO₄(s) + H₂O(l)

Using Hess's law, the net change in enthalpy for this reaction could be obtained as:

ΔHr = ΔH(1) + ¹/₂ΔH(2)

ΔHr = +113kJ + ¹/₂ -775kJ

ΔHr = -275 kJ

Final answer:

To produce 22 g of CO₂, we calculate the moles of CO₂ and use the 1:1 molar ratio with O₂ to find that 16 g of oxygen gas is required, according to the balanced chemical equation for the reaction.

Explanation:

Calculating Mass of Oxygen Required to Produce Carbon Dioxide

To determine the mass of oxygen gas required to produce 22 g of carbon dioxide in the reaction C(s) + O₂(g)
ightarrow CO₂(g), we will first consider the molar masses of the substances involved. The molar mass of carbon dioxide (CO₂) is 44.009 g/mol, which means 1 mole of CO₂ weighs 44.009 grams. Since carbon is a pure element in its solid form, its molar mass is equivalent to its atomic mass, which is 12.0 g/mol. The molar mass of oxygen (O₂) is 32.0 g/mol because one mole of O₂ consists of 2 atoms of oxygen and the atomic mass of oxygen is 16.0 g/mol per atom.

Using the stoichiometry from the balanced chemical equation, we know that 1 mole of C will react with 1 mole of O₂ to produce 1 mole of CO₂. Therefore, if we have 22 g of CO₂, we can calculate the moles of CO₂ and then the moles of O₂ required:

Calculate moles of CO₂ produced: (22 g CO₂) / (44.009 g/mol) = 0.5 mol CO₂.

We need 0.5 mol of O2 since the mole ratio is 1:1.

Calculate mass of O₂ required: (0.5 mol O₂) times (32.0 g/mol) = 16 g O₂.

So, the mass of oxygen gas required to produce 22 g of carbon dioxide is 16 g.

Answer:

Explanation:

M