A student performs an experiment several times to determine the enthalpy of combustion of naphthalene, an organic compound with the formula C10H8, and collects the following data: −5181. 6kJmol, −5181. 9kJmol, −5183. 5kJmol, −5180. 1kJmol, and −5184. 2kJmol. What is the relative standard deviation (RSD) for this set of data? Give the answer as a positive number

According to the given statement The pH of the resulting solution is 13.03.

To calculate the pH of the resulting solution, we need to know the concentration of the thiamine hydrochloride ions in the solution.

The Ka value of thiamine hydrochloride is 5.3 x 10^-27. Since thiamine hydrochloride is a weak acid, it dissociates in water according to the following equation:

HC12-H17ON4SCl2 (s) <-> H+ (aq) + C12-H17ON4SCl2- (aq)

The product of the acid and the base concentrations is equal to the acid dissociation constant (Ka)

H+(aq) * C12-H17ON4SCl2- (aq) = Ka

Molarity (M) = moles of solute/liters of solution

3.0 x 10^-25 g of thiamine hydrochloride is dissolved in 1.00 L of water. The molar mass of thiamine hydrochloride is 337.29 g/mol. So we can calculate the number of moles of thiamine hydrochloride in the solution.

moles = mass / molar mass

moles = 3.0 x 10^-25 / 337.29 = 8.94 x 10^-28

Molarity = moles / liters = 8.94 x 10^-28 / 1 = 8.94 x 10^-28 M

Now we can substitute the concentration of thiamine hydrochloride into the equation for the acid dissociation constant.

Ka = [H+] * [C12-H17ON4SCl2-]

Ka = (x)(x) = 8.94 x 10^-28

We know the Ka value and we know the concentration of thiamine hydrochloride ions. So we can use the Ka value and the thiamine hydrochloride concentration to calculate the concentration of H+ ions in the solution.

x^2 = 8.94 x 10^-28

x = √(8.94 x 10^-28)

x = 9.4 x 10^-14

[H+] = x = 9.4 x 10^-14 M

The pH of the solution is calculated by taking the negative log of the H+ concentration:

pH = -log(9.4 x 10^-14)

pH = 13.03

To know more about Thiamine hydrochloride visit: brainly.com/question/8928076

#SPJ4

Answer:

Explanation:

Aluminium hydroxide is amphoteric. 3 HCl + Al(OH)3 → AlCl3 + 3 H2O. In bases, it acts a Lewis acid by taking an electron pair from the hydroxide ions: Al(OH)3 + OH− → Al(OH)

Water is called a ‘universal solvent' because water can dissolve much more substances than any other liquid found in nature but water cannot dissolve every substance.

Water is referred to as a "universal solvent" because it has a considerably wider range of natural solvent properties than any other liquid. However, water is not capable of dissolving all compounds.

For instance, water cannot dissolve hydroxides, fats, or waxes because oppositely charged particles are not very soluble in water. Hydrogen and oxygen atoms are arranged polarly in water molecules.

The oxygen atom has a negative charge, while the hydrogen atom on one side has a positive charge.The water molecule can more easily attach to various compounds thanks to these charges.

To learn more about universal solvent refer to:

https://brainly.com/question/1834245

#SPJ1

Because it can dissolve a greater variety of chemicals than any other natural liquid, water is referred to as a "universal solvent," though it does not dissolve all substances. The option  C is true.

In comparison to other liquids, water has a much larger spectrum of natural solvent qualities, earning it the moniker "universal solvent". Nevertheless, not all substances can be dissolved by water.

Because water is not highly soluble in oppositely charged particles, it cannot dissolve hydroxides, fats, or waxes, for example. Water molecules have polar arrangements of the hydrogen and oxygen atoms.

In contrast to the hydrogen atom on one side, which has a positive charge, the oxygen atom has a negative charge.

These charges allow the water molecule to more readily bind to different substances.

For more information about universal solvent kindly visit to brainly.com/question/1834245

#SPJ1

The name of an isotope that has 14 protons and 14 neutrons is Silicon-28

The total number of protons and neutrons in an isotope's nucleus is referred to as the mass number. This is due to the fact that each proton and neutron has a mass of one atomic mass unit.

We may get the mass of the atom by multiplying the total number of protons and neutrons by 1 amu.

The atomic number Z is 14 if there are 14 protons. Z being the quantity of large positively charged nuclear particles by definition.

Silicon is what we have if Z is the atom's identity and Z=14. The isotope of the element is 28S because the element may contain more or fewer neutrons than Z, where neutrons are heavy, neutrally charged nuclear particles.

Silicon-28 is the isotope with 14 protons and 14 neutrons.

Learn more about neutron at brainly.com/question/29248303

#SPJ4

Soname's dearest wishes for the future are to become a successful leading lady and to continue to use her talents and passions to inspire and empower people.

She also hopes to continue to learn, grow, and make a positive impact on the world. Soname dreams of financial stability and security so that she can continue to provide for her family and be an example for her community. She wishes to continue to build a successful career in entertainment, both on and off screen, and to be an example of success for her peers.

Lastly, she wishes to use her voice and platform to advocate for social justice and to make a difference in the world. Soname has a strong desire to make a lasting impact and to leave a legacy that she can be proud of. She is determined to use her hard work and determination to make her dreams come true and to make the world a better place.

To know more being successful lady:

brainly.com/question/1110307

#SPJ4

According to the given statement a) 39.367kJ  heat is required AND b) 62.3kJ heat is required.

One mole of a chemical is equal to 6.022 x 1023 particles (or formula units) (ionic compound). The molar mass of a reagent is the amount of 1 mole of that chemical. In put it another way, it gives you the amount of grams per molecule of a material.

Heat required to convert 42.0 g of ethanol at 35 °C to the vapor phase at 78 °C can be calculated by;

H = mcθ + mL

m = mass of ethanol

c = specific heat capacity of ethanol

θ = temperature change

L = Latent heat of vaporization of ethanol

Adding  values;

H = (42 × 2.3 × (78 - 35)) + (42/46 × 38.56 × 10^3)

H = 4154 + 35207

H = 39.367 kJ

b) Heat required to convert the same amount of ethanol at - 155°C to the vapor phase at 78 °C;

H = mLfus + mcθ + mLvap

H =  (42/46 ×  5.02 × 10^3) +  (42 × 2.3 × 78 - (- 155)) + (42/46 × 38.56 × 10^3)

H = 4583 + 22508 + 35207

H = 62.3 kJ

To know more about Molar mass visit:

https://brainly.com/question/12127540            

#SPJ4

Na ion concentration will remain constant if you increase the overall number of Na ions while also increasing the volume of water in which they are dissolved.

The amount of material in a certain area is referred to as concentration in chemistry. Another definition states that concentration is the ratio of a solution's solute to its entire solution or solvent. Mass per unit volume is a common way to express concentration. However, moles or units of volume can also be used to express the solute concentration. Concentration could be per unit mass instead of volume. Concentration can be computed for any mixture, despite often being used with chemical solutions.

By mathematically dividing the mass, moles, or volume of the solute by the mass, moles, or volume of the solution, one may calculate the concentration (or, less commonly, the solvent).

Learn more about concentration here:

https://brainly.com/question/10725862

#SPJ4

Answer:

1.26 moles

Explanation:

Applying Avogadro's constant.

1 mole of every substance, has a particle of 6.02×10²³

From the question,

If,

1 mole of Neon contains 6.02×10²³ particles

Therefore,

x moles of Neon will contain 7.6×10²³ particles

x = (7.6×10²³)/(6.02×10²³)

x = 1.26 moles.

Hence the number of moles of Neon present is 1.26 moles

Fluorine reacts with xenon but iodine doesn't because fluorine is highly electronegative, it can pull electrons from xenon which is a noble gas and rarely reactive. On the other hand, iodine has low electronegativity and is least reactivity, so doesn't react with xenon.

Fluorine and iodine belongs to the family of halogens with the general electronic configuration ns²np⁵ . So, they have the tendency to attract electrons in their valence shell. Xenon, on the other hand is a noble gas with a stable electronic configuration ns²np⁶.

In family of halogens, Fluorine has the highest electronegativity and iodine has the least due to increase in its size. So, more electronegative fluorine has the tendency to form compounds with xenon whereas both iodine and xenon being less reactive cannot form a bond together.

To know more about reaction of fluorine with xenon here

https://brainly.com/question/2269881

#SPJ4

Answer:

The original solution’s concentration was 3.09 M.

Explanation:

Dilution is the reduction of the concentration of a chemical substance in a solution, and consists simply of adding solvent to an existing solution.

The quantity or mass of the solute is not changed but only that of the solvent. That is, as only solvent is being added, the consequence is that by not increasing the amount of solute but if the amount of solvent, the concentration of the solute decreases.

A dilution is expressed as:

Cinitial*Vinitial = Cfinal*Vfinal

In this case:

Replacing:

Cinitial*8.4 L = 0.65 M*40 L

Solving:

[tex]Cinitial=\frac{0.65 M*40 L}{8.4 L}[/tex]

Cinitial= 3.09 M

The original solution’s concentration was 3.09 M.

Option B, Bonding pair-bonding pair, lone pair-bonding pair, lone pair-lone pair. The electrons in bonding pairs are repulsion held relatively closely together, and are involved in the formation of a chemical bond.

The repulsion between two bonding pairs is relatively weak, as they are attracted to the positively charged nuclei of the atoms they are bonding. The repulsion between a lone pair of electrons and a bonding pair of electrons is generally stronger than that between two bonding pairs because the lone pair is not involved in bonding and tends to be held further away from the nucleus, causing the electron cloud to be larger and thus a stronger repulsion because the two lone pairs are not involved in bonding, and are held relatively far away from the nuclei, causing the electron clouds to be larger and thus a stronger repulsion

Learn more about repulsion here:

https://brainly.com/question/25143253

#SPJ4

The type of reaction is a double replacement reaction. In a double replacement reaction, the positive ions of two compounds switch places to form two new compounds.

The balanced chemical equation for the reaction between magnesium and lead(II) nitrate is:

Mg(s) + Pb(NO3)2(aq) -> Mg(NO3)2(aq) + Pb(s)

In this equation, the magnesium and lead ions switch places to form the new compounds magnesium nitrate and lead. The coefficients in front of the compounds indicate the number of moles of that substance that are involved in the reaction. The subscripts indicate the number of atoms of each element in each compound.

To know more about double replacement reaction, visit:

brainly.com/question/29224660

#SPJ4

Answer:

oxoacids

Explanation:

Acids such as HNO3, H2SO4, which contain oxygen, hydrogen, and other elements are called oxoacids

According to Gay-Lussac's law, the pressure of the gas at the cooler temperature is 132.95 torr.

It is defined as a gas law which states that the pressure which is exerted by the gas directly varies with its temperature and at a constant volume.The law was proposed by Joseph Gay-Lussac in the year 1808.

The pressure of the gas at constant volume reduces constantly as it is cooled till it undergoes condensation .

It is given as, P₁/T₁=P₂/T₂ , therefore P₂=225×65/110=132.95 torr.

Therefore,the pressure of the gas at the cooler temperature is 132.95 torr.

Learn more about Gay-Lussac's law,here:

https://brainly.com/question/2683502

#SPJ1

Answer:

Add coefficients to some of the compounds to balance the number of atoms.

Explanation:

The balanced equation should be CH4 + 2 O2 = CO2 + 2 H2O

So you see we had to use coefficients in front of some of the compounds to balance number of atoms.

Cribbing is the tool we use prior to making your first extrication cut in the vehicle

Before making the first extrication cut, it is important to stabilize the vehicle to prevent it from moving and to ensure the safety of the individuals involved in the extrication process. One tool that is commonly used to stabilize a vehicle during extrication is a set of stabilizing struts, also known as cribbing. Cribbing is a set of wooden or composite blocks that are placed under the vehicle to support it and prevent it from moving. The cribbing is typically placed at strategic points, such as the frame of the vehicle or the wheels, to provide a stable base for the vehicle.Additionally, other tools like wheel chocks, jacks, and air bags may be used to provide additional support and stability. The extrication team will assess the situation and choose the most appropriate tool to stabilize the vehicle.

Learn more about extrication  here:

https://brainly.com/question/29910467

#SPJ4

The atomic number is the number of protons in the nucleus of an atom and it directly affects the properties of an element. The atomic number also determines the element's place in the periodic table, which allows us to predict the properties of an element based on its atomic number.

As the atomic number increases, the number of protons in the nucleus increases and so does the atomic number. This increase in protons also increases the number of electrons in the atom. The number and arrangement of electrons in an atom directly affect its chemical behavior and thus the properties of the element.

The atomic number also determines the element's position on the periodic table, and elements with similar atomic numbers have similar chemical and physical properties. For example, elements in the same vertical row (group) have similar chemical properties, and elements in the same horizontal row (period) have similar electronic configurations of their atoms.

The atomic number also affects the reactivity of an element. Elements with lower atomic numbers tend to be more reactive than elements with higher atomic numbers.

Learn more about atomic number here: https://brainly.com/question/621740

#SPJ4

Remove dry chemicals. Remove contaminated clothing or jewelry. Bandage the burn. Rinse again if needed.

A chemical burn is infection and destruction of human tissue because of exposure to a chemical, generally with the aid of direct contact with the chemical or its fumes. Chemical burns can occur in the domestic, at work or school, or as a result of an twist of fate or assault. although few humans in the united states of america die after contact with chemical substances in the home, many substances not unusual in both living and garage areas can do extreme damage.

To know more about chemicals click here

https://brainly.com/question/26487468

#SPJ4

My answers are by the way they are written p-phy c-che

Answer:

128.98 g/Mol

Explanation:

ΔTb = Kb * m * i

Where;

ΔTb = boiling point elevation

Kb = boiling point constant

m = molality of the solution

i = Van't Hoff factor

Hence;

Where molality = number of moles of solute/mass of solvent in Kg

Number of moles of solute = mass/Molar mass

So;

80.61 - 80.10 = 2.53 * 13g/M/0.5 * 1

Where M is the molar mass of the solute

0.51 = 2.53 * 13g/M/0.5

0.51 = 2.53 * 13/M * 1/0.5

0.51 = 32.89/M * 1/0.5

0.51 * 0.5 = 32.89/M

0.255 M = 32.89

M = 32.89/0.255

M= 128.98 g/Mol

Cool in cold or lukewarm water for 20 minutes.

This should be done as soon as possible after an injury. Never use ice, ice water, cream, or greasy substances like butter on the burn. Be careful to keep the airways open when treating burn victims. Associated smoke inhalation injuries are very common, especially when the patient is burned in an enclosed space such as a room or building. Even people who have been burned outdoors can inhale smoke. Stop the burning process as soon as possible. Remove all clothing and jewelry near the burned area.

Learn more about inhalation injuries visit:

brainly.com/question/28271345

#SPJ4

We can use the distance when the meter stick fell before you caught it to figure out your reaction time.  

Meterstick is either a straightedge or foldable ruler which is used to measure a  length, and is especially common in the construction industry. They are often made up of wood or plastic, and often have metal or plastic joints so that they can be folded together. Metersticks are usually divided with lines for each millimeter (1000 per meter) and numerical markings as per centimeter (100 per meter), with the numbers or either in centi- or millimeter.

Formula is the basis: d = 1/2 gt2. In this formula, “d” is equals to the distance the object fell, “g” equals to gravitational acceleration (9.8 m/s2), and “t” is the time the object was falling.

To know more about meterstick here

https://brainly.com/question/29690562

#SPJ4

An alpha helix is a type of secondary structure in proteins. It is a right-handed, coiled-coil structure that is stabilized by hydrogen bonds between the peptide backbone amide nitrogen and carbonyl oxygens of every fourth residue.

1st residue hydrogen-bonded to 5th residue (that is, residue n is H-bonded to residue n+4) - Alpha Helix

All NH groups point in the same direction - Beta Sheet

successive R groups point in opposite directions - Beta Sheet

1st residue (that is, residue n is hydrogen bonded to residue n+3) - Beta Turn

All contains-NH hydrogen bonded to C=O - Alpha Helix

In summary, the first phrase describes an Alpha Helix, the second and third phrases describe Beta Sheets, and the fourth phrase describes a Beta Turn, the fifth phrase also describes an Alpha Helix.

Learn more about Alpha Helix here:

https://brainly.com/question/14465166

#SPJ4

Answer:

a process where the products released in one reaction are the stimuli and reactants for another reaction

Explanation:

A chemical reaction is described as a process in which the products promote or spread the reaction, which may accelerate dramatically under certain conditions.

Answer: chain reaction

Explanation: a chain reaction is a series of chemical reactions where the products of the reaction contribute to the reactants of another reaction. as a series of events that are each caused by the previous event. If a trash can falls over and this scares a cat who then jumps and knocks over a glass of water, thats a chain reaction. The trash can fall is the initial event, and the end result is the glass getting knocked over.

The correct answer is option C: Low temperature only, because entropy decreases during freezing.

When a substance changes from a gas to a solid, the entropy (measure of disorder) of the system decreases. This is because the solid has a more ordered structure than the gas. The decrease in entropy is accompanied by a decrease in temperature and an increase in enthalpy (heat content).For a process to be spontaneous, the entropy change must be positive, so the freezing of methane is spontaneous only if the temperature of the surroundings is lower than the temperature of the methane. Thus, the heat released from the exothermic process will be absorbed by the surroundings, the temperature of the methane will decrease, and the entropy of the system increases, driving the process towards completion.

Learn more about entropy here:

https://brainly.com/question/15025401

#SPJ4

The complete question is :

Methane freezing is an exothermic process. Which of the following best describes the temperature conditions that are most likely to cause this spontaneous change? Because entropy increases during freezing, any temperature. Because entropy decreases during freezing, any temperature. Only at low temperatures because entropy decreases during freezing. Only at high temperatures, as entropy

The answer is 20.46g.

As we know that

1 mole of CO2 has 6.02 x 10^23 molecules of CO2.

Now, let's say x moles of CO2 has 2.80 x 10^23 molecules of CO2.

Therefore,

               x = 2.80 x 10^23 / 6.02 x 10^23 = 0.465

As, M = nmr

  M = 0.465 *( 12 + 2x16)

      = 0.465 *( 12 + 32)

      = 0.465 * 44

      = 20.46g

Nitrate NO 2 It is inappropriate to use one of the following ions' names and formulas.

Herbicides, explosives, defoliants, paper, leather, dyes, matches, and inks are all made from it. It's also used to make cosmetics and medications. An inorganic salt of sodium with the counter-ion chlorate is known as sodium chlorate. It serves as both a herbicide and an oxidizing agent for bleaching paper.

Chlorate, an anion, can enter drinking water through a number of different causes, such as the use of hypochlorite or chlorine dioxide as disinfectants, the oxidation of hypochlorite or chlorite by ozone, and pesticide runoff or paper mill discharges that contaminate the source water.

To know more about chlorate visit:

https://brainly.com/question/5923839

#SPJ4

in the given following elements when the central atom could exhibit sp 3 d 2 hybridization , Sulphur(S)  can exhibit the asked configuration.

Z=16  for Sulphur

Electronic configuration [tex]1S^{2} 2S^{2} 2P^{6} 3S^{2} 3P^{2} 3D^{0}4S^{0}[/tex]   here we can clearly see that the energy difference between the 3p and 3d shell is very so sulphur can exhibit the asked configuration.

Z=6 for Carbon C - [tex]1S^{2} 2S^{2} 2P^{2}[/tex]

Z=7 for Nitrogen N- [tex]1S^{2} 2S^{2} 2P^{3}[/tex]

Z=5 for Boron B- [tex]1S^{2} 2S^{2} 2P^{1}[/tex]

Here we can clearly see that the atom is very small d the shell is not present in the configuration above also the energy difference between the shells will be high as they are close to the nucleus hence the asked configuration can not be exhibited.

To learn more about Electronic Configuration

brainly.com/question/29757010

#SPJ4

Answer:

38.51g NaOH

Explanation:

NaOH=39.907 g/mol

0.965 mol NaOH X 39.90g NaoH/1 mol NaOH= 38.51 g NaOH

Answer:ne

Explanation: