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a student dissolves 10.8 g of sodium chloride ( nacl)in 300.g of water in a well-insulated open cup. he then observes the temperature of the water fall from 23.0∘c to 22.6∘c over the course of 9 minutes. use this data, and any information you need from the aleks data resource, to answer the questions below about this reaction: nacl(s)→na+(aq)+cl−(aq) you can

Question: A Student Dissolves 10.8 G Of Sodium Chloride ( NaCl)In 300.G Of Water In A Well-Insulated Open Cup. He Then Observes The Temperature Of The Water Fall From 23.0∘C To 22.6∘C Over The Course Of 9 Minutes. Use This Data, And Any Information You Need From The ALEKS Data Resource, To Answer The Questions Below About This Reaction: NaCl(S)→Na+(Aq)+Cl−(Aq) You Can




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To determine whether this reaction is exothermic, endothermic, or neither, we need to consider the change in temperature that occurred when the NaCl dissolved in water. In this case, the temperature of the water fell from23.0°C to 22.6°C over the course of 9 minutes, indicating that heat was released by the reaction. Therefore, we can conclude that the reaction is exothermic.


a. exothermic


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A student dissolves 10.8 g of sodium chloride ( NaCl)in 300.g of water in a well-insulated open cup. He then observes the temperature of the water fall from 23.0∘C to 22.6∘C over the course of 9 minutes. Use this data, and any information you need from the ALEKS Data resource, to answer the questions below about this reaction: NaCl(s)→Na+(aq)+Cl−(aq) You can make any reasonable assumptions about the physical properties of the solution. Be sure answers you caiculate using measured data are rounded to 1 significant digit. Note for advanced students' it's possible the student did not do the experiment carefully, and the values you calculate may not be the same as the known and published values for this reaction.

Ariana is playing basketball with her friends. They are using an orange basketball. Because all visible light waves except orange are absorbed by the ball.

The correct answer is A.

The correct answer is A.

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Approximately 2.22 x \(10^2^5\) molecules of nitrogen and 6.29 x \(10^2^4\)molecules of oxygen are present in the International Space Station (ISS). If the oxygen and CO2 scrubber system fails, four astronauts on the ISS have approximately 73 hours before the air becomes unbreathable and they risk losing consciousness.

First, we convert the volume of the ISS to liters: 932 \(m^3\) = 932,000 liters.

Next, we calculate the number of moles of each gas using the ideal gas law equation. The pressure is given as 1 atm, and the temperature is 293 K.

For nitrogen:

PV = nRT

(1 atm)(932,000 L) = n(0.0821 L·atm/(mol·K))(293 K)

n ≈ 2.93 x \(10^4\) moles

For oxygen:

PV = nRT

(1 atm)(932,000 L) = n(0.0821 L·atm/(mol·K))(293 K)

n ≈ 8.29 x \(10^3\) moles

Finally, we convert the number of moles to the number of molecules by multiplying by Avogadro's number (6.022 x \(10^2^3\) molecules/mol).

For nitrogen:

2.93 x \(10^4\) moles × 6.022 x \(10^2^3\) molecules/mol ≈ 2.22 x \(10^2^5\) molecules

For oxygen:

8.29 x \(10^3\) moles × 6.022 x \(10^2^3\) molecules/mol ≈ 6.29 x \(10^2^4\) molecules

Therefore, approximately 2.22 x \(10^2^5\) molecules of nitrogen and 6.29 x \(10^2^4\) molecules of oxygen are present in the ISS.

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If we had used 4 grams of NaOH instead of 2 grams, the heat gained by the solution would have been higher.

The term enthalpy has to do with the heat that could be emitted or evolved in a given reaction. We know that in a neutralization reaction, there is an evolution of heat and as such the reaction  vessel would feel warm at the end of the reaction.

Also, the enthalpy would depend on the amount of the limiting reactant. In this case, the limiting reactant would be the sodium hydroxide and as such the enthalpy would affected by a change in the amount of the sodium hydroxide.

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The number of miles one can drive if a car gets 29.50 miles per gallon with 12.00 gallons of gas would be

The car in question can cover a distance of 29.50 miles per gallon of gas and there is a total of 12.00 gallons of gas available. If one gallon can cover a distance of 29.50 miles, then the distance that the 12 gallons can cover can be calculated using dimensional analysis as follows:

1 gallon = 29.50 miles

12 gallons = 28.50 x 12

                 = 342 miles

In other words, if one gallon can cover a distance of 29.50 miles, then the 12.00 gallons of gas will cover a total distance of 342 miles.

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Answer:

Explanation:Using the equation, PV=nRT, you can solve this problem.

P= 3.5 kPa V=? n= 0.55 moles of air T= 295K R= 8.314 (L kPa/mol K)

We use the constant rate of 8.314 because we are using kilopascals in this problem.

Using simple algebra we get-

V = (0.55 moles)(8.314 L kPa/mol k)(295 K) / 3.5 kPa

Using the calculator, we would get the answer of 385.4132857 L.

And whatever the significant figure is asked for, for example, 3 significant figures: the answer would be 385 liters.

Answer:

According to the law of conservation of matter, the mixture should weigh 175 g

Explanation:

The law of conservation of matter is one of the basic guiding principles of chemical reactions.

It states that matter is neither created nor destroyed but can be converted from one form to another.

Although this law has been faulted with advances in science and technology, it is still found basically useful.

So applying the law to the question at hand, it is expected that all the mass of the sugar gets added to all the mass of the water

This brings the total mass to 25 + 150 = 175 grams

The weight of the mixture of sugar and water has been 175 grams.

The law of conservation of mass has been based on the fact that the mass has neither been created and nor destroyed.

The law of conservation of mass stated the combination of the two compounds results in the final solution being the sum of the two reactants.

For example, the mass of a solution of compounds A and B will be:

Mass of A + Mass of B = Mass of solution

The sugar solution formed has been consisted of:

Sugar = 25 grams

Water = 150 grams.

According to the law of conservation of mass, the weight of the mixture has been:

Weight of mixture = Weight of sugar + Weight of water

Weight of mixture = 25 grams + 150 grams

Weight of mixture = 175 grams.

The weight of the mixture of sugar and water has been 175 grams.

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Answer:

A: ZnS(s) + 2O2(g) --> ZnSO4(s)

Explanation:

;) good luck

Answer:

The answer is A or the first choice

Explanation:

ZnS(s) + 2O2(g) Right arrow. ZnSO4(s)

HAVE A GREAT DAY STAY SAFE

When iron-rich materials cool below their Curie temperature, they may preserve the orientation of the magnetic field.

The Curie temperature is the temperature at which a ferromagnetic material loses its magnetic properties. When a ferromagnetic material is heated to its Curie temperature, the thermal energy causes the magnetic moments of the atoms in the material to become disordered, which causes the material to lose its magnetic field. When the material cools below its Curie temperature, the magnetic moments of the atoms become ordered again, but the orientation of the magnetic field may not be preserved. However, in iron-rich materials, if the cooling process is slow enough, the orientation of the magnetic field can be preserved, creating a record of the Earth's magnetic field at the time the material cooled. This property has been used to study the Earth's magnetic field history by analyzing the magnetic properties of rocks and sediments.

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Answer: 2400kg/m3

Explanation:  p=m/3   m over 3

                       33.6g/14cm3

                       2.4g/cm3

                       2400kg/m3                        

Answer:

This question is to vague. PS: what are you talking about?

Explanation:

This question is to vague. PS: what are you talking about?

paper chromatography, in analytical chemistry, technique for separating dissolved chemical substances by taking advantage of their different rates of migration across sheets of paper..The method consists of applying the test solution or sample as a spot near one corner of a sheet of filter paper.

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If two independent estimates of σ2 (variance) are close together, it suggests that the variability of sample means can be attributed to the true underlying population variance.

When conducting statistical analysis, researchers often estimate the population variance, σ2, using different samples. If the resulting estimates are relatively similar, it indicates that the observed variability in the is likely due to the true variability in the population. This implies that the samples are representative and that the estimated variance accurately captures the true variance. Conversely, if the estimates differ significantly, it suggests that other factors may be influencing the variability of the sample means, such as sampling bias or random fluctuations.

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Explanation:

hope this helps you.

a) The boron diffusion took approximately 22 minutes if the diffusion temperature was 1100°C.

b) The sheet resistance of the layer can be calculated using the formula R_sheet = 1/(q*μ*n_surf), where q is the electron charge, μ is the electron mobility, and n_surf is the surface concentration. Plugging in the given values, we get R_sheet = 7.34 Ω/sq.

c) The dose in the layer can be calculated by integrating the Gaussian profile. The total dose comes out to be 2.2 x 10^15 /cm2.

d) To design a diffusion schedule for the pre-deposition step, we need to determine the diffusion coefficient of boron at the deposition temperature.

Assuming a diffusion coefficient of 5 x 10^-11 cm^2/s, the pre-deposition step can be carried out at 900°C for 2 hours to achieve a dose of 5 x 10^18 /cm^3.

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Answer:

The answer is B. sound; light

Explanation:

Answer:

Explanation:

you will have to grabe  a towle or a meten and take it off

The average speed is approximately 19.0 kilometers per hour.

When we say the average speed is approximately 19.0 kilometers per hour, it means that over a given time period, the object or person in question traveled a total distance of 19.0 kilometers divided by the total time it took to cover that distance. In this case, the given speed is 19 kilometers per hour.

To calculate the average speed, we use the formula:

Average Speed = Total Distance / Total Time

In the given question, the speed is already mentioned as 19 kilometers per hour. So, we can conclude that the total distance covered is 19 kilometers.

However, to find the total time taken, we need more information. The question only provides the speed but not the duration of the journey. Without knowing the total time, we cannot determine the average speed accurately. Therefore, in the absence of further information about the time, we can only state that the average speed is approximately 19.0 kilometers per hour based on the given speed.

Average speed and how it is calculated by considering the total distance and total time traveled.

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Answer:

26 protons, 30 neutrons, and 26 electrons

Explanation:

There are total  26 protons, 30 neutrons and 26 electrons in an Fe atom.

The electron has a negative charge. The symbol for electrons is (e–). An electron’s atomic mass unit is (5.45×10–4). The orbits of electrons are located outside the nucleus of the atoms.

A proton has a positive charge. (p+) is the symbol for protons. The proton’s atomic mass unit is 1. Protons are found within the nucleus of atoms. A proton has a mass of (1.672×10–27 kg).

A neutron is either neutrally charged or uncharged. The symbol for neutrons is (n⁰). The neutron’s atomic mass unit is one. Neutrons are also found inside the nucleus.

These all combinedly makes an atom, hence  there are total  26 protons, 30 neutrons and 26 electrons in an Fe atom.

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Answer:

You can identify an unknown substance by measuring its density and comparing your result to a list of known densities. Density = mass/volume. . You divide the mass by the volume and compare the density to a list of known densities.

The limiting reactant​ : Fe

Reaction

3Fe + 4H₂O ⇒ Fe₃O₄ + 4H₂

mass of H₂O = 10 g

mol H₂O (MW=18 g/mol) :

\(\tt mol=\dfrac{mass}{MW}\\\\mol=\dfrac{10}{18}=0.56\)

mass of Fe = 16.8 g

mol Fe(MW=56 g/mol) :

\(\tt mol=\dfrac{16.8}{56}=0.3\)

Limiting reactant : the smallest ratio between mol : reaction coefficient

Fe :

\(\tt \dfrac{0.3}{3}=0.1\)

H₂O :

\(\tt \dfrac{0.56}{4}=0.14\)

Fe as limiting reactant

Answer:

To calculate the pH of an aqueous solution you need to know the concentration of the hydronium ion in moles per liter (molarity). The pH is then calculated using the expression: pH = - log [H3O+].

Explanation:

Answer:

24,000 grams

Explanation:

The test is frequently employed as a preliminary test to eliminate the possibility of carbonyl groups present.

The 2,4-DNP derivative is formed when 2,4-Dinitrophenyl hydrazine reacts with a carbonyl compound namely an aldehyde or a ketone in a weakly acidic medium. It leads to the formation of a 2,4-dinitrophenyl hydrazone.

This is generally true.

The 2,4-DNP (2,4-dinitrophenylhydrazine) test is a common qualitative test used to detect the presence of aldehydes and ketones. When a sample containing an aldehyde or ketone is treated with 2,4-DNP reagent, the 2,4-DNP reacts with the carbonyl group of the aldehyde or ketone to form a yellow to orange-colored precipitate.

If the test is positive and a yellowish precipitate is observed, it indicates the presence of an aldehyde or ketone in the sample. On the other hand, if the test is negative and an orange solution is observed, it indicates the absence of aldehydes or ketones in the sample.

It is important to note that some compounds other than aldehydes and ketones may also give a positive 2,4-DNP test. Therefore, the test is often used as a preliminary test to narrow down the possibilities of the presence of carbonyl groups, and further confirmatory tests may be required for a definitive identification of the compound.

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Answer:

jayfeather friend me

Explanation:

In a toasty kitchen, your dough may proof in as little as an hour (or less!). When the temperatures dip, it can take much longer—upwards of two or even three hours.

The mass of barium in 288 mg of barium arsenate (Ba3(AsO4)2) is approximately 0.462 mg.

The molar mass of Ba3(AsO4)2 can be calculated by summing the atomic masses of each element in the compound. The atomic masses are as follows:

Barium (Ba): 137.33 g/mol

Arsenic (As): 74.92 g/mol

Oxygen (O): 16.00 g/mol

Molar mass of Ba3(AsO4)2:

= (3 * 137.33 g/mol) + (2 * (74.92 g/mol + 4 * 16.00 g/mol))

= 411.99 g/mol + 207.84 g/mol

= 619.83 g/mol

Now, we can calculate the mass of barium in 288 mg of barium arsenate using the molar mass and the given mass.

Mass of barium:

= (mass of barium arsenate / molar mass of barium arsenate) * molar mass of barium

= (288 mg / 619.83 g/mol) * 411.99 g/mol

= 0.462 mg

The mass of barium in 288 mg of barium arsenate (Ba3(AsO4)2) is approximately 0.462 mg.

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Answer:Simple Machine: Any of various devices that function in a manner basic to any machine, such as a lever, pulley, wedge, screw, or inclined plane. Complex Machine: A device consisting of two or more simple machines working together. ... A wedge is driven or forced between objects to split, lift, or make them stronger.

Explanation:

Answer:

26

Explanation: