Suppose that 25 gg of each of the following substances is initially at 25.0 ∘C∘C. What is the final temperature of each substance upon absorbing 2.30 kJkJ of heat? Part A gold

Answer:

Twelve electrons are exchanged in the iron-oxygen redox reaction.

Explanation:

Oxidation and reduction reactions are complementary processes. Every oxidation must be accompanied by a reduction and vice versa. In fact, the both processes are not essentially different but are different aspects of the same process hence the coinage 'redox reaction'.

In the redox reaction under consideration, iron is the electron donor while oxygen is the electron acceptor. The half equations are shown below;

Oxidation half equation;

4Fe---> 4Fe^3+ + 12e

Reduction half equation;

3O2 + 12e ----> 6O^2-

Ionic equation of the process;

4Fe^3+ + 6O^2- -----> 2Fe2O3

Hence it can be clearly seen that twelve electrons were transferred in the process.

Answer:

6

Explanation:

The reaction occurs in The anode of an electrochemical cell. Option B is the correct option

This refers to a device that can produce electrical energy from the chemical reactions occurring in it, or use the electrical energy to facilitate chemical reactions. ​

An electrochemical cell splits the oxidant and reductant in a way that allows electrons to flow through an external circuit from the reductant (which gets oxidized) to the oxidant (which causes reduction) while preventing them from physically touching each other.

The two compartments of an electrochemical cell where the half-reactions occur are called the anode(Oxidation occurs here) and the cathode (Reduction occurs here), and they must have an electrode that you can connect to the external circuit.

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Answer:

The correct answer is option D

Explanation:

The enzyme enolase is categorized as a metalloenzyme that carries out the catalytic reaction of 2-phosphoglycerate to phosphoenolpyruvate conversion. Several kinetic and spectroscopic methods have been applied to study the role of the divalent metal ions Mg+2 (magnesium ions) involved in the reaction. Both the ions have been shown to coordinate with the carboxylic group of the substrate and product. The coordination provides stability to the intermediate steps in the general base catalysis of enolase (proton abstraction by a base), thereby providing maximum activity to the dimeric molecule.

The enzyme is a molecule that acts as a catalyst while the ions are supposed to facilitate the action of the enzyme. So, option a and b are incorrect. In the reaction, the proton abstraction takes place by a base, not an acid and so, option C is incorrect. The transition state and the intermediate steps are stabilized which facilitates the base catalysis and so, option E is incorrect.

Answer: To facilitate  general base catalysis. Thus option D is correct.

Explanation:

Enolase enzyme is classified as a metalloenzyme that performs the catalytic reaction of converting 2-phosphoglycerate to phosphoenolpyruvate. Various kinetic and spectroscopic methods were used to investigate the role of the divalent Mg+2 metal ions (magnesium ions) involved in the reaction. Both ions were shown to coordinate to the carboxyl group of the substrate and the product. The coordination ensures the stability of the intermediate steps in the general base catalysis of enolase(extraction of the proton by the base) and thus the maximum activity of the dimeric molecule.

An enzyme is a molecule that acts as a catalyst, while ions are believed to facilitate the action of the enzyme .Therefore, options a and b are invalid. The reaction involves the extraction of the proton from the base, not the acid, so option C is incorrect. The transition state and intermediate phases are stabilized, facilitating base catalysis, so option E is wrong.

Based on the data provided for the two monoprotic acids, the molarity of the acid HA is 0.181 M.

Using the balanced chemical equation for the reaction between HA and NaOH, we can write :

HA + NaOH → NaA + H2O

We know that the number of moles of NaOH used in the titration is given by : n(NaOH) = M(NaOH) x V(NaOH)

where

M(NaOH) is the molarity of NaOH

V(NaOH) is the volume of NaOH used.

We know that the number of moles of NaOH used is equal to the number of moles of HA in the first flask.

Thus, n(HA) = n(NaOH)

We can calculate the number of moles of HA from the volume of NaOH used :

n(HA) = M(NaOH) x V(NaOH) = 0.0906 M x 0.0873 L = 0.00789 mol

Since the acid HA is monoprotic, the number of moles of HA is equal to the number of moles of H+ in the solution.

Thus, n(H+) = n(HA)

We can use the volume and concentration of the acid in the second flask to calculate the number of moles of H+ in the solution. The volume of the solution in the second flask is 50.0 mL, which is equal to 0.0500 L. The total volume of the HA and HB solutions in the second flask is 37.2 mL + (50.0 mL - 37.2 mL) = 12.8 mL.

Since HB is also monoprotic, the number of moles of H+ contributed by HB is equal to the number of moles of HB in the solution.

We can use the total volume and concentration of the solution in the second flask to calculate the number of moles of HB :

n(HB) = C(HB) x V(HB) = C(HB) x (12.8 mL/1000)

where C(HB) is the concentration of HB in the solution.

The concentration of the solution in the second flask is : n(H+)_total = n(HA) + n(HB)

= C(HA) x (43.5 mL/1000) + C(HB) x (12.8 mL/1000)

Since the acid HA is monoprotic, the number of moles of H+ contributed by HA is equal to the number of moles of HA in the solution.

We can use the total number of moles of H+ and HA in the solution to calculate the molarity of the acid HA :

C(HA) = n(HA) / (43.5 mL/1000) = n(H+)_total / (43.5 mL/1000)

Therefore,C(HA) = n(H+) / (43.5 mL/1000) = [0.00789 mol] / [43.5 mL/1000] = 0.181 M

Therefore, the molarity of the acid HA is 0.181 M.

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None of the combinations would provide a cell potential of exactly 0.5 V by adjusting the half-cell ion concentrations. Therefore, the correct answer is option D.

To set up a cell with a potential of exactly 0.5 V by adjusting the half-cell ion concentrations, we need to find a combination of half-cells that will provide the desired potential. Looking at the options provided:

A) Cu/Cu2+ and Pb/Pb2+: The standard reduction potentials for Cu2+ and Pb2+ are +0.34 V and -0.13 V, respectively. Combining these two half-cells would not give a cell potential of exactly 0.5 V.

B) Zn/Zn2+ and Cu/Cu2+: The standard reduction potentials for Zn2+ and Cu2+ are -0.76 V and +0.34 V, respectively. Combining these two half-cells would not give a cell potential of exactly 0.5 V.

C) Zn/Zn2+ and Pb/Pb2+: The standard reduction potentials for Zn2+ and Pb2+ are -0.76 V and -0.13 V, respectively. Combining these two half-cells would not give a cell potential of exactly 0.5 V.

D) none of these B) Zn/Zn2+ and Cu/Cu2+ would be the best cell combination to use when setting up a cell with a potential of exactly 0.5 V by adjusting the half-cell ion concentrations.

Based on the above explanation, none of the combinations would provide a cell potential of exactly 0.5 V.

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To set up a cell with a potential of exactly 0.5 V, the best choice among the given options is \(Zn/Zn2^+\) and \(Cu/Cu2^+\). The correct option is B.

The standard reduction potentials for the half-reactions are as follows:

\(Zn2^+(aq) + 2e^- \rightarrow Zn(s) : E ^{\circ} = -0.76 V\)

\(Cu2^+(aq) + 2e^- \rightarrow Cu(s) : E^\circ = +0.34 V\)

To obtain a cell potential of 0.5 V, the reduction potential of the anode (Zn) should be higher than the reduction potential of the cathode (Cu). Thus, the \(Zn/Zn2^+\) half-cell should be connected to the negative terminal (anode) and the \(Cu/Cu2^+\) half-cell to the positive terminal (cathode) of the cell.

To prepare the solution, you need to dilute the 1 M metal ion solution. The specific calculations depend on the initial volume and concentration of the metal ion solution.

Therefore, it is recommended to consult your lab notebook and TA for accurate volume and concentration calculations to achieve the desired 0.5 V cell potential.

Therefore, the correct answer is B.

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Answer:

11.5

Explanation:

1 mole of Na has 6.022 × 10^23

so 6.95 x 10^24 / 6.022 × 10^23 = 11.5 moles

The molarity of the ethanol is 11.29M .

What is molarity ?

Molar concentration, also known as molarity, amount concentration, or substance concentration, is a unit used to describe the amount of a substance in a solution expressed as a percentage of its volume. The number of moles per litre, denoted by the unit symbol mol/L or mol/dm3 in SI units, is the most widely used unit for molarity in chemistry. One mol/L of a solution's concentration is referred to as one molar, or 1 M.

The mass of one mole of ethanol is 46.07 g/mol.

The number of mole in 50.500 g ethanol is 50.500/46.07 = 1.096158 mole.

We know that,

Mass = Density × Volume.

The final volume of the solution 750.0ml and the density of the solution is 1.20g/ml.

The mass of the solution is 1.20g/ml × 750.0ml = 900 gm.

The mass of water is (900-50.500) = 849.5 gm.

So the term molarity is defined as:

One of the most common units of concentration, expressed in M. It is defined as no moles of solute in 1 liter of solution.

The molarity of the solution is:

(1.09615 × 1000)/ 849.5  = 1.29M (approx.).

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Answer:Are these free points

Explanation: because if so I want them

Answer: 18

Explanation:hope this help

The chemical changes that occur during fatty acid synthesis involve the reduction of carbonyl groups and the condensation of acetyl-CoA molecules to form long chains of carbon atoms. So, the correct option is b) reduction and condensation.

The chemical change that occurs during fatty acid synthesis involves the condensation of two-carbon units in the form of acetyl-CoA to form long chains of carbon atoms, which are then further processed to form various types of fatty acids. Two main types of reactions occur during this process: reduction and condensation.

During the reduction reaction, NADPH donates a pair of electrons to the carbonyl group of the acetyl-CoA molecule, leading to the formation of a hydroxyl group (-OH) and an acetyl group (-CO-CH3). This reduction reaction is catalyzed by enzymes called reductases and occurs in several steps along the fatty acid synthesis pathway.

The condensation reaction involves the formation of a carbon-carbon bond between two acetyl-CoA molecules, releasing a molecule of CoA-SH in the process. This reaction is catalyzed by enzymes called condensing enzymes and occurs repeatedly until the desired chain length is achieved.

So, the correct option is b) reduction and condensation. Overall, These chemical reactions are essential for the synthesis of various types of fatty acids, which are important building blocks for cellular membranes and energy storage molecules.

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Lithium (Li) is less reactive than potassium (K) because the valence electrons in lithium atoms are closer to the nuclei and harder to remove. Option D

The periodic table has to do with an arrangement of the elements in their order of reactivity. We know that the periodic table is arranged in groups and periods. The groups are the vertical portions while the periods are the horizontal portions.

Given that the reactivity would depend on the position of an element in the periodic table, we would look at where the elements that are to be considered are found in the periodic table.

We know that the elements that occur down the group for the metals are more reactive because they are more shielded thus they leave the attractive force of the nucleus much more easily.

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Missing parts;

Elements are organized on the periodic table based on their properties. Which statement correctly predicts and explains the chemical reactivity of two different metals? Barium (Ba) is less reactive than calcium (Ca) because the valence electrons in calcium atoms are farther from the nuclei and harder to remove. Strontium (Sr) is more reactive than magnesium (Mg) because the valence electrons in strontium atoms are farther from the nuclei and harder to remove. Rubidium (Rb) is more reactive than sodium (Na) because the valence electrons in sodium atoms are closer to the nuclei and easier to remove. Lithium (Li) is less reactive than potassium (K) because the valence electrons in lithium atoms are closer to the nuclei and harder to remove.

Answer:

Chlorophyll absorbs certain wavelengths of light within the visible light spectrum. ... Green light is not absorbed but reflected, making the plant appear green.

Answer:

Why does chlorophyll b appear yellow-green?

Explanation:

As for your final task for this lesson, you will need to prepare and deliver a speech on a familiar issue. You are free to decide on what issue to discuss, but your speech should only range two (2) to three (3) minutes only. You will also have to employ the different techniques in public speaking cited in this lesson.

Camouflage is not a general adaptation which is therefore denoted as option A.

This is referred to as any heritable trait that helps an organism, such as a plant or animal, survive and reproduce in its environment.

It is also called cryptic coloration, is a defense or tactic that organisms use to disguise their appearance, usually to blend in with their surroundings. Organisms use camouflage to mask their location, identity, and movement and it used by most prey to avoid predators, and for predators to sneak up on prey.

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Answer:

PbCr

Explanation:

Answer:

Thermal Energy

Explanation:

Energy that is dissipated or absorbed as heat is in the form of thermal energy.

The atomic mass number tells us the number of neutrons and protons in the nucleus of an atom.

Answer:

So the total mass is 50 plus 150 grams the heat capacity 4.18 joules per gram per degree C. And the temperature change is 36 minus 25 and so we can calculate Delta H for the reaction that takes place.

Explanation:

The resonance form that is not a valid resonance of the cyclohexadienyl cation intermediate in the bromination of benzene is the one where the positive charge is located on the carbon atom adjacent to the bromine atom.

To obtain the correct resonances of the cyclohexadienyl cation intermediate, we first start by drawing the Lewis structure of the benzene molecule. In the presence of the bromine molecule and a Lewis acid catalyst, one of the pi electrons from the benzene ring is donated to the bromine molecule, creating a sigma bond between the two atoms and a positively charged cyclohexadienyl cation intermediate.

The correct resonance structures of the cyclohexadienyl cation intermediate can be obtained by moving the positive charge to each of the six carbon atoms in the ring, one at a time. This creates six resonance structures, each with a partial positive charge on a different carbon atom in the ring.

However, the resonance form where the positive charge is located on the carbon atom adjacent to the bromine atom is not valid, as it violates the octet rule and creates a highly unstable carbocation. Therefore, this resonance form is not a resonance of the cyclohexadienyl cation intermediate in the bromination of benzene.

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Answer:

C. It does not emit electromagnetic radiation.

Explanation:

Right now, Dark Matter is only a theory. Scientist proposed this to counter some of the strange phenomenon with matter in space.

Scientists know little about dark matter. Some say it's one of the driving forces of the universe. Currently, scientists have no way of measuring or identifying dark matter.

the closest value is C, 85.

hope it helps!!!!

85 is the estimate value that is obtained from a sample of which size is likely to be closest to the actual parameter value of a population. Therefore, the correct option is option C.

A population is the entire set of people in a group, whether that group is a country or a collection of people who share a certain trait. A population is the group of people where a statistical sample has been collected in statistics. Hence, a population is any collection of people who have something in common.

A statistically substantial chunk of a population, rather than the full population, may also be referred to as a sample. For this reason, the standard deviation, meaning standard error, of a statistical study of a sample from the full population must be disclosed. Only a population-wide analysis would have zero standard deviation. 85 is the estimate value that is obtained from a sample of which size is likely to be closest to the actual parameter value of a population.

Therefore, the correct option is option C.

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Answer:

for pH 13 it = strong based the ph 2 is= weak acid

Explanation:

Answer:

there is only one pic

Explanation:

but if its oki can u type itt

Pbcl2 precipitate when 275 ml of a 0.134 m solution of pb(no3)2 is added to 125 ml of 0.0339 m solution of nacl? the ksp of pbcl2 is 1.17e-5.

Given that,

The volume of NaCl = 125 ml

Concentration of NaCl = 0.0339 m

The volume of Pb(NO3)2 = 275 ml

Concentration of Pb(NO3)2 = 0.134 m

K(eq) = 1.17 × 10(-5) --------(1)

Total volume = 275 + 125 = 400 ml

Pb(NO3)2 ------- Pb(+2) + 2 NO3(-)

at t = 0 0.134 0 0

at t = t 0 0.134 0.134

NaCl -------- Na(+) + Cl(+)

at t = 0 0. 0339 0 0

at t = t 0 0.0339 0.0339

PbCl2 ---------- Pb(+2) + 2Cl(-)

Q(sp) = [Pb+2] [ Cl-]^2

By substituting the values of conc. of all the ions, we get Pbcl2 precipitate when 275 ml of a 0.134 m solution of pb(no3)2 is added to 125 ml of 0.0339 m solution of nacl? the ksp of pbcl2 is 1.17e-5.

= (275 × 0.134/ 400) (125 × 0.0339/400)^2

= 9.8 × 10(-6)

As we noticed that, Ksp > Qsp

Therefore, PbCl2 will not precipitate.

Thus, we concluded that the Pbcl2 precipitate when 275 ml of a 0.134 m solution of pb(no3)2 is added to 125 ml of 0.0339 m solution of nacl? the ksp of pbcl2 is 1.17e-5.

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Answer:

When the Ruler is bent the energy stored in it will be potential energy, When the ruler will be released this potential energy will be then converted into the Kinetic energy as a result the ruler will move Vibrations.

The energy conservation law can be applied here

K1 + U1 = K2 + U2

K1 - initial kinetic energy

U1 - Initial potential energy

K2 - final kinetic energy

U2 - final potential energy

Energy is known commonly as the ability to do work or move a matter. The type of energy that is stored is called potential energy.

if the ruler is released at the bent end, the object or pebbles on it will fly. If you hold two positive charges near each other, they have potential energy because they will move if you release them.

If the object released is fired straight up into the air, it begins with a high kinetic energy. As it rises, it slows down due to the force of gravity pulling it toward the earth.

Due to the release, the object place on the ruler rises, its gravitational potential energy is therefore increasing and its kinetic energy is decreasing.

When the object reaches the top of its arc, it kinetic energy is zero and its potential energy is maximum.

Then gravity still to pull the object down the earth and the object will fall toward the earth and just as it falls down, its speed increases and its height decreases.

So, its kinetic energy will thus increases as it falls and its potential energy decreases.

When the object has returns to its original height, its kinetic energy will be the same as when it started upward.

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In consideration of Henry's law the molar mass of organic compound is 0.24 grams.

The molar mass of a chemical compound defined as the mass of a sample of that compound devided by the amount of substance which is the number of moles in that sample,measured in moles.

Sol-One of three asks what the mass of water is in grams and two and 1/2 liters of paper of Equis, 12.5% sodium chloride, fifty five°C. This problem tells us that pure H2O is one hundred eighteen  tour at fifty five*° C.So the first thing that we have to do here is figure out wth e um, the mole fraction of thermal fractions, I suppose, of both sodium chloride and water.

We know those 2.5 liters. We're looking for this number of moles here. Ideal gas constant 0.8 to 6 leader atmospheres over mole Calvin. And then we have to convert, um, Celsius, the 55 degrees C to Calvin. So we always rmember that simply 55 degrees Celsius plus two year and 73 which gets US 328 Calvin. So solving all of that for the number of moles, then that gives us 0.133 off water and 2.5 liters of vapor. So last step, then, is to just convert that to Graham's, since the problem asks for a mass and not by the number moles. So you can plug that, , basically into, uh, the molecular by it it and it does weight of water, just 18.2 grand's for mold. And that gives us keeping significant figures in mind. 0.24 grams.

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The attributes of the genetic code include all of the following except B. Each codon specifies more than one amino acid.

A. Each codon consists of 3 nucleotides: This is a correct attribute of the genetic code. Codons are made up of three consecutive nucleotides, which form the basic unit of the genetic code.

B. Each codon specifies more than one amino acid: This is incorrect. Each codon typically specifies only one amino acid. However, there are some exceptions called "ambiguous codons" where a single codon can code for more than one amino acid, but they are relatively rare.

C. Codons are non-overlapping: This is a correct attribute of the genetic code. Codons are read sequentially and are not overlapping. Each codon starts at a specific position in the DNA or mRNA sequence.

D. Most amino acids are specified by more than one codon: This is a correct attribute of the genetic code. With a few exceptions, most amino acids are encoded by multiple codons. This redundancy provides some level of error tolerance and allows for variations in the DNA sequence without affecting the encoded protein.

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Answer:

the mass is of potassium is 88.38 rounded to the nearest hunndred.

Explanation:

The volume of gas is directly proportional to the amount (moles) of gas.

The volume of a gas is directly proportional to the amount (moles) of gas. When the amount (moles) of a gas increases, the volume of the gas will also increase proportionally.

The relationship between volume (V) and the number of moles (n) of a gas is expressed by the Ideal Gas Law,

PV = nRT.

It describes how the pressure (P), volume (V), number of moles (n), and temperature (T) of a gas are related. According to this law, at constant temperature and pressure, the volume of a gas is directly proportional to the amount (moles) of gas.Therefore, the statement that describes the relationship between volume (V) and number of moles (n) illustrated in the plot for a gas at constant temperature and pressure is "The volume of gas is directly proportional to the amount (moles) of gas.

"This means that if the amount of gas in a container is doubled while the temperature and pressure remain the same, the volume of the gas will also double.

Similarly, if the amount of gas is halved, the volume will also be halved, given that the temperature and pressure remain the same. This relationship between the volume and amount of gas is important in several scientific applications, including gas laws and stoichiometry.

The volume of gas is directly proportional to the amount (moles) of gas.

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Answer:

0.60g of the fungus can be allowed

Explanation:

The maximum concentration of the fungus that can be allowed is 25 ppb, that is 25mg/t.

As the peanuts are 24t, the mass of fungus that can be allowed is:

24t * (25mg/t) = 600mg of the fungus can be allowed. In grams are:

600mg * (1g/1000mg) =

Answer:

0.5g of toxin

Explanation:

ppb = mass of solute/ mass of solution x 10^9

ppb = mass of fungus/ mass of peanuts x 10^9

25ppb = (x/2 x 10^7g) x 10^9

x = (25)(2 x 10^7g)/ 10^9

x = 0.5g of toxin

x represented the unknown mass of solute (fungus), in which we solved for. We already knew we were using the ppb formula, which is mass of solute/ mass of solution x 10^9, because the question mentions that there are 25ppb of peanuts in the shipments. In the calculations, you can see that I substituted the mass of peanuts with 2 x 10^7g. I did this because the question mentions that there are 20t of peanuts and since each t = 1000kg, I multiped 20 x 1000 to get 20 000kg. In my formula for ppb, I know that I have to use grams of solution, not kilograms. Knowing this, we follow the formula for ppb and substitute our known values and solving for unknown values.