for each burned food sample, it is important to get a mass before and after the burning takes place. what would happen to the calculated energy (compared to the actual energy) per gram released if a student does notget a mass after the sample is burned?

Warm air rises at the equator and cold air sinks at the poles creating is B convection currents.

Convection can be described as the single or multiphase fluid flow which can take place spontaneously  as a result of the combined effects of material property heterogeneity  as well as the body forces on a fluid,  especially with density and gravity.

It should be noted that in case whereby Warm air rises at the equator and cold, there will be a phenonmenon in which the air sinks at the poles which will bring about the convection currents.

Therefore, option B is correct.

Learn more about convection currents at:

https://brainly.com/question/11514482

#SPJ1

Answer: Mass of 1 atom of Cu=63.546 A.M.U

=63.546×1.66×10^(-27) kg

= 105.48636×10^(-27) kg

So,

Mass of 1.2×1038 atoms of Cu

= 1.2×1028×105.48636×10^(-27) kg

= 130127.973696×10^(-27) kg ANS !!!!

Ka=5.3*10^(−11) By definition, Ka will be equal to Ka= [H3O+]*[A-]/[HA]Now use the pH of the solution to determine the equilibrium concentration of hydronium

We shall first ascertain the pKa of the solution before calculating the Ka. The pH of the solution and the pKa of the solution are equal at the equivalence point. As a result, we can quickly calculate the value of Ka using a titration curve and the equation Ka = - log pKa.

The ionisation constant (Ka) of formic acid can be calculated by the following formula;-

Ka = {[H+] * [HCOO-]} / [HCOOH]

Therefore you would need to know the value of each of the three concentration values on the right-hand side of the equation.

The equation for the dissociation of formic acid is;-

HCOOH ⇌ H+ + HCOO-

From this equation it can be seen that, at any degree of ionisation, the moles of H+ ions produced is equivalent to the moles of HCOO- ions. Therefore we can say that;-

[H+] = [HCOO-]

So, the equation for Ka in this case becomes;-

Ka = {[H+] * [H+]} / [HCOOH]

Ka = [H+]^2 / [HCOOH]

So, we have simplified our Ka formula down to two values, the H+ ion concentration [H+], and the concentration of undissociated formic acid [HCOOH]. To calculate the Ka for formic acid, we therefore need to either measure, or be given these values.

For example, if we started with a solution of formic acid which was 0.1M, we could measure its pH. Since pH = -log[H+], we could then calculate the H+ ion concentration and solve the Ka equation.

As it turns out the pH of a 0.1M formic acid solution is 2.38. Therefore, for this formic acid solution;-

-log([H+]) = 2.38

log([H+]) = -2.38

[H+] =10^(-2.38)

[H+] = 0.0042 M

Also, since formic is a relatively weak acid we can use the original solution concentration. i.e. [HCOOH] = 0.1M

Now we can solve the Ka equation we simplified above;-

Ka = [H+]^2 / [HCOOH]

Ka = (0.0042 )^2 / 0.1

Ka = 1.764 * 10^-4

Learn more about titration curve here:

https://brainly.com/question/29590776

#SPJ4

The concentration is 1.66 x 10⁻²⁴M if exactly one solute molecule exists in one milliliter of solution.

A molecule is the simplest unit of the a substance that keeps its content and properties. It is made up of two or maybe more atoms that are joined together by hydrogen bonds.

1 molar solution is 1 mole in 1 liter.

1 mole = 6.022 x 10²³ molecules

1 molecule = 1/6.022 x 10²³ moles

= 0.166 x 10⁻²³ moles

So 0.166 x10⁻²³23 moles in 1 L means concentration = 1.66 x 10⁻²⁴M

Since 1 molecule solute means M= 1.66 x 10⁻²⁴M

1 x 10⁻²⁵M has only fraction of a solute molecule

To know more about Molecule visit:

https://brainly.com/question/19556990

#SPJ4

The compounds which shows UV absorbance between 200-400 nm are Caffeine, Salicylic acid, Acetaminophen and Aspirin.

What is chemical bond?

Atoms in molecules are joined by chemical bonds. Electrostatic forces between negatively charged electrons and positively charged atomic nuclei result in bonds.

What is UV?

The wavelength of ultraviolet (UV) radiation ranges from 10 nanometers (with a corresponding frequency of about 30 PHz) to 400 nanometers (750 THz), which is shorter than that of visible light but longer than X-rays.

The compounds C, D and E shows UV absorbance between 200-400 nm.

The compounds which shows UV absorbance between 200-400 nm are Caffeine, Salicylic acid, Acetaminophen and Aspirin.

Therefore, compounds which shows UV absorbance between 200-400 nm are Caffeine, Salicylic acid, Acetaminophen and Aspirin.

Learn more about chemical bonds from the given link.

https://brainly.com/question/819068

#SPJ4

In response to the question, 48.2 gram of CH4 contain 1.81*10²⁴ molecules of CH4.

A molecule is the simplest unit of any material that is composed of one or more elements and is capable of existing independently while maintaining all of the material's physical and chemical characteristics. Further atom division occurs within molecules. For instance, the symbols for the atom and molecule are O and O2, respectively.

Large biomolecules can be divided into four categories: lipids, proteins, nucleic acids, and carbohydrates. Monomers called oligosaccharides, which comprise oxygen, oxygen, or hydrogen, are the building blocks of carbs.

To know more about Molecules visit;

https://brainly.com/question/19556990

#SPJ4

The complete question is-

How many molecules of ch4 are in 48.2 g of this compound?

(a). 3.00

(b). 4.00

(c). 2.90*10²⁵

(d). 5.00*10²⁴

(e). 1.81*10²⁴

Your base titrant volume reading was 1.18 mL at the start of the titration. The base titrant volume was 23.00 mL when the titration was finished and the endpoint was reached.

When just enough titrant is added to completely neutralize the analyte solution during titration, this is known as the equivalence point. Molecules of base equal molecular weights of acid at the equivalence point in an acid-base titration and the solution is made up entirely of salt and water.

Learn more about the Molecules,

https://brainly.com/question/475709

#SPJ4,

Answer: Actual Yield

The methyl butanoate is the ester. the ester contains C = O, carbonyl stretching  is found about the 1735 cm⁻¹.

The methyl butanoate is from the ester family. it is also called as methyl butyrate. it is colorless liquid the odor of methyl butanoate is like an apple. methyl butanoate is used as solvent. the structure of methyl butanoate can be determine by the IR spectra. it is also used as an flavoring agent.

The methyl butanoate if from the methyl ester of butyric acid. the methyl butanoate is present is several plant product in very small amount. it is formed by the distillation from the essential oils of vegetable.

To learn more about methyl butanoate here

https://brainly.com/question/29649524

#SPJ4

When sports trainers transfer cold packs, which have temperatures dropped when ammonium nitrate dissolves in water when ice cannot be transported, the process is endothermic (Î"H > 0).

For the growth of plants in particular, and therefore for other species that get their nourishment from plants, they serve as a significant supply of nitrogen. Nitrates are used for a number of things, such as fertilizers, food preservatives, drugs, and explosives.

Nitrate poisoning may be dangerous, especially for infants. Methemoglobinemia may result from excessive nitrate consumption, which can alter how blood delivers oxygen (also known as blue baby syndrome). The risk of developing methemoglobinemia is higher in infants who are bottle-fed and under six months old.

To know more about Nitrates visit:

https://brainly.com/question/5346392

#SPJ4

When conduct electricity an ion from this excited state, 54.4 eV of energy must be provided.

What is an definition of energy?

Energy is referred to and by scientists as the capacity for work. People have figured out how to transform energy from one type to another and then use it to accomplish tasks, making modern civilization possible. Chemical, electrical, radiant, mechanical, thermal, and nuclear energy are the six main types of energy. Additional forms including electrochemical, acoustic, electromagnetic, and others might be addressed in other studies.

Briefing:

Since this electron has an energy of,

E₂=-Z²*13.6/n² eV

=-4²*13.6/2² eV

=-54.4eV

To know more about energy visit:

brainly.com/question/28175012

#SPJ4

Mass of sucrose is 378 grams

[tex]\% \mathrm{~m} / \mathrm{V}=\frac{\text { Mass of sucrose }}{\text { Volume of solution }}[/tex]

[tex]\text { Let } m=\text { mass of sucrose }[/tex]

[tex]\frac{40.0 \mathrm{~g}}{100 \mathrm{~mL}}=\frac{m}{795 \mathrm{~mL}}[/tex]

[tex]m=\frac{40.0 \mathrm{~g} \times 795}{100}[/tex]

   = 378 g

What is mass?

A scientific term used to represent the density and kind of atoms in any given article is called mass.

What is sucrose?

A disaccharide is a sugar composed of glucose and fructose subunits is sucrose. It is produced naturally in plants and is the main ingredient of white sugar.

To know more about mass, visit:-

https://brainly.com/question/3359951

#SPJ4

The final concentration of the Randyne in grams per milliliter = 0.011 g/mL

What is Solution?

In science, a solution is a particular kind of mixture made up of two or more substances. The definition of a solution specifically relates to a certain class of homogeneous mixture, that is, a mixture with a uniform composition and no discernible differences between its constituent parts. This is distinct from a heterogeneous mixture, where each component can be seen separately.

Although mixtures of gases or solids can also be included in solutions, liquid mixtures are the most common type. A solvent and a solute are needed to create a solution.

As we know

C1V1 = C2V2

C1 and C2 = concentration of solution 1 and 2 respectively

V1 and V2 = Volume of solution 1 and 2 respectively

Substituting the given values, we get -

The final concentration of the Randyne in grams per milliliter = 0.011 g/mL

Learn more about Solution from given link

https://brainly.com/question/25785824

#SPJ4

The mass of O₂ in grams required to completely react with 0.025 g of C₃H₈ is 0.091 g.

The reaction is given as :

C₃H₈  +  5O₂  ----->   3CO₂   +   4H₂O

The mass of C₃H₈ = 0.025 g

mola mass of C₃H₈ = 44.1 g/mol

moles of C₃H₈ = mass / molar mass

                         = 0.025 / 44.1

                         = 0.00056 mol

moles of O₂  = 5 × 0.000567

                     = 0.00284 mol

molar mass of O₂  = 32 g/mol

mass of O₂  = moles × molar mass

                    = 0.00248 × 32

                    = 0.091 g

The mass of Oxygen required is 0.091 g to react with 0.025 g of C₃H₈ .

To learn more about moles here

https://brainly.com/question/1691083

#SPJ4

The number of  moles of hydrogen peroxide will be oxidized by 0.0435 moles of potassium permanganate an acidic solution is 0.054375

What is titration?

Titration is a technique used to gauge an unknown substance's concentration. Titrations, for instance, can be used to calculate the volume of solution needed to neutralize an acid. Titrations are used in redox titrations to determine the amount of the oxidizing agent that is required to oxidize a substance.

Here,

H2o2(aq} −→ 2O2 + 2H+ 2e-

MnO4−(aq)+8H++5e−→Mn2+(aq)+4H2O(l)

Combining the oxidation and reduction half~reactions for hydrogen peroxide and permanganate ion, respectively, and writing  the balanced chemical equation for the overall reaction between H2O2 and Mn04- in acid solution gives us

5 H2O2 + 2 MnO4– + 6 H+ -------> 2 Mn2+ + 8H2O + 5 O2

The mole ratio is 5 hydrogen peroxide molecules to 2 permanganate molecules in the reaction

Therefore moles oxidized by  0.0435 moles of potassium permanganate, using the ratio, is 0.054375

To know more about titration from the given link

https://brainly.com/question/186765

#SPJ4

Ethylenediamine tetraacetic acid (EDTA)  substances that give a visibly colored solution can be analyzed using spectrophotometry. cu2 forms a complex with edta that is pale blue in aqueous solution.

Abdominal cramps, nauseousness, vomiting, diarrhea, headaches, low blood pressure, skin issues, and fever are just a few of the side effects that EDTA can bring on. It is NOT SAFE to consume EDTA for more than 5 to 7 days or in doses greater than 3 grams per day. Overdosing can result in mortality, dangerously low calcium levels, and renal injury. Absorption spectrophotometry, which examines how radiation and certain light spectra are absorbed, and Ultraviolet-Visible Range spectrophotometry, which examines how certain light spectra are reflected from a given source, are the two main forms of spectrophotometry that are used.

Learn more about spectrophotometry here:

https://brainly.com/question/3948698

#SPJ4

The answer is Redox Reaction.

What are Redox Reactions?

A redox reaction can be defined as a chemical reaction in which electrons are transferred between two reactants participating in it. This transfer of electrons can be identified by observing the changes in the oxidation states of the reacting species.

The loss of electrons and the corresponding increase in the oxidation state of a given reactant is called oxidation. The gain of electrons and the corresponding decrease in the oxidation state of a reactant is called reduction.

Electron-accepting species which tend to undergo a reduction in redox reactions are called oxidizing agents. An electron-donating species which tends to hand over electrons can be referred to as a reducing agent. These species tend to undergo oxidation. It can be noted that any redox reaction can be broken down into two half-reactions, namely the oxidation half-reaction and the reduction half-reaction.

Learn more about redox reactions here :

https://brainly.com/question/13293425?referrer=searchResults

#SPJ4

These numbers show that the highest mean O3 concentration occurs during the daytime and is higher than it is at night. While there is a greater mean NO concentration at night.

The NO, NO2 and NOx diurnal cycles resemble double waves. The morning peak is larger than the evening peak in size. The morning peak of NO2 arrives 1-2 hours after the NO peak, while the morning peaks of O3 appear roughly 6 hours, 5 hours, and 2 hours after the NO2 peak, respectively.

The higher levels of NOx coincide with the peak hours for vehicular emissions, which are in the morning and evening.

To know more about ozone visit:-

https://brainly.com/question/14330630

#SPJ4

27 moles of ammonia must also be present.

The no of moles of water in solution = 6 moles

mole fraction of ammonia = number of moles of ammonia/ Total no of moles

0.818 = no of moles of ammonia / no of moles of ammonia + number of moles of water

0.818 = n1 / n1 + 6

n1  = 4.908/ 0.182 = 27 mole

One of the industrial chemicals made most frequently in the US is ammonia (NH3). In addition to being naturally occurring in both individuals and the environment, it is employed in industry and commerce. Numerous biological functions require ammonia, which also acts as a precursor to the creation of amino acids and nucleotides. Ammonia is created in soil by bacteria and is a component of the nitrogen cycle in the environment. Ammonia is also created naturally through the breakdown of organic material, such as plants, animals, and animal excrement. Approximately 80% of the ammonia produced by industry is used as fertilizer in agriculture. In addition to these uses, ammonia is also employed in the production of polymers, explosives, textiles, insecticides, dyes, and other compounds. It also serves as a refrigerant gas.

Learn more about ammonia here:

https://brainly.com/question/15409518

#SPJ4

The molar concentration of a solution created by decomposing 25 g of Fe(NO₃)₃ in 250.0 ml of water is 0.413M.

We divided the number of mole of solute by both the given quantity of liters of solutions to determine the mole ratio of a solution.

The quantity of a material in a specific volume of solution is known as its molarity (M). The number of moles of something like a solute each liter of a solution is known as molarity.

Briefing:

m= 25,

Molar mass(M) of Fe(NO₃)₃ = 241.86g/mol

V= 0.25dm3,

Molarity(C) = ?

Moles = m/M= C×V

Substitute and Simplify

m/M = C×V

25/241.86= C×0.25

Molarity(C) = 0.413M

To know more about molarity visit:

https://brainly.com/question/8732513

#SPJ4

The molecular geometry of the chf3 molecule is tetrahedral , and the molecule is polar.

The atomic configuration of a molecule in three dimensions is known as molecular geometry. Bond lengths, bond angles, torsional angles, and any other geometrical factors that affect each atom's position are all included in this, along with the molecule's overall form. Molecule Geometries. Linear, trigonal planar, tetrahedral, trigonal bipyramidal, and octahedral are the five primary shapes of simple molecules as described by the VSEPR theory.

A molecule is said to be tetrahedral when its centre atom has four bonds and no lone pairs. There are 109.5° angles between the atoms that are bound to the core atom and are situated at its four corners. Four substituents are positioned in the four corners of a tetrahedron, with the central atom in a tetrahedral molecular geometry being in the centre.

learn more about molecular geometry here

https://brainly.com/question/7558603

#SPJ4

Answer:

See explanation

Explanation:

The change in ph when 9.00 ml of 0.100 m hcl(aq) is added to 100.0 ml of a buffer solution that is 0.100 m in nh3(aq) and 0.100 m in nh4cl(aq). consult

1)

Step 1: Calculate initial pH

Kb = 1.8*10^-5

pKb = - log (Kb)

= - log(1.8*10^-5)

= 4.745

use:

pOH = pKb + log {[conjugate acid]/[base]}

= 4.745+ log {0.1/0.1}

= 4.745

use:

PH = 14 - pOH

= 14 - 4.7447

= 9.2553

Step 2: Calculate pH after adding HCl

mol of HCl added = 0.1M *9.0 mL = 0.9 mmol

NH3 will react with H+ to form NH4+

Before Reaction:

mol of NH3 = 0.1 M *100.0 mL

mol of NH3 = 10 mmol

mol of NH4+ = 0.1 M *100.0 mL

mol of NH4+ = 10 mmol

after reaction,

mol of NH3 = mol present initially - mol added

mmol of NH3 = (10 - 0.9) mmol

mol of NH3 = 9.1 mmol

mol of NH4+ = mol present initially + mol added

mol of NH4+ = (10 + 0.9) mmol

mol of NH4+ = 10.9 mmol

since volume is both in numerator and denominator, we can use mol instead of concentration

Kb = 1.8*10^-5

pKb = - log (Kb)

= - log(1.8*10^-5)

= 4.745

After the reaction, the following equation holds true: mol of NH3 = mol present initially - mol added mmol of NH3 = (10 - 0.9) mmol mol of NH3 = 9.1 mmol mol of NH4+ = mol present initially + mol added mol of NH4+ = (10 + 0.9) Since volume appears in both the numerator and denominator of the equation, we can use mol in place of concentration: mmol mol of NH4+ = 10.9 mmol

Kb = 1.8*10-5 pKb = -log(Kb) = -log(1.8*10-5) = 4.745

Employ: pOH = pKb + log [conjugate acid]/[base] = 4.745 + log [10.9/9.1] = 4.823

employ: PH = 14 - pOH = 14 - 4.8231 = 9.1769

Step 3: Subtract the final pH from the initial pH to arrive at a change delta pH of -0.0784 (9.1769 - 9.2553).

Incorrect: -0.0784

2) The reaction between NH4+ and OH- will produce NH3 when mol of NaOH supplied is 0.1M *9.0 mL = 0.9 mmol.

NH3 = 0.1 M * 100.0 mL mol of NH3 = 10 mmol NH4+ = 0.1 M * 100.0 mL mol of NH4+ = 10 mmol

After reaction, the equation is: Mol of NH3 = Mol originally present + Mol of NH3 added = (10 + 0.9). mmol mol of NH3 equals 10.9 mmol mol of NH4+ equals mol initially present minus mol added mol of NH4+ = (10 - 0.9) Since volume is in both the numerator and the denominator of mmol mol of NH4+ = 9.1 mmol, we can substitute mol for concentration.

Kb = 1.8*10-5 pKb = -log(Kb) = -log(1.8*10-5) = 4.745

Make use of: pOH = pKb + log [conjugate acid]/[base] = 4.745 + log [9.1/10.9] = 4.666

employ: PH = 14 - pOH = 14 - 4.6663 = 9.3337

delta pH = final pH - initial pH

= 9.3337 - 9.2553

= 0.0784

Answer: 0.0784

Learn more about pH here:

https://brainly.com/question/15289741

#SPJ4

Ionic solids are therefore insulators, which is the right response. Choice "B."

An insulator is any substance that prevents the energy—such as electricity, heat, or cold—from the moving through it easily. Good insulators include glass, plastic, rubber, and  the wood.

The most popular and generally accessible type of insulation, blanket, comes in the form of rolls or batts. Flexible fibres, most frequently fibreglass, make up this substance. Additionally, natural fibres like cotton and sheep's wool are available in batts and rolls, along with artificial fibers and mineral wool.

To know more about insulators visit:

https://brainly.com/question/24909989

#SPJ4

A molar solution is one that contains 1 mole of a material in 1 liter of water.

The concentration is 1.66x10-24 M if there is exactly one molecule of the solute in one litre of solution.

In this situation, 1 mole is defined as 6.02x10²³ particles, or molecules. As a conversion factor, consider the following:

1 mole = 6.02 x 10²³ molecules.

When only 1 molecule of the solute is present, use this conversion factor to determine moles of the solute:1.66x10-24 moles are equal to (1 molecule)/((1 mole)/(6.02x1023 molecules)).

Only moles remain after the molecules cancel.

By definition, concentration is the number of moles of a solute per litre. Divide the volume, in this case 1.0L, by the 1.66x10-24 moles to get:

1.66x10-24 molar, or 1.66x10-24 M, = (1.66x10-24 moles solute)/(1.0 litre).

A way to express solution concentration is by molarity. It is described as the quantity of solute that dissolves in one liter of solution.

Learn more about molar solution here:

https://brainly.com/question/16587536

#SPJ4

The marble chips are reacted with a solution that produces a gas that turns the lime water milky.

This means that the gas produced is carbon dioxide. Therefore, carbonates only produce carbon dioxide gas when treated with acids. Marble chips are alkaline compounds that react with hydrochloric acid to produce carbon dioxide calcium chloride and water. Marble chips are composed of calcium carbonate.

Adding dilute hydrochloric acid to a piece of marble which is calcium carbonate forms calcium chloride, water, and carbon dioxide. Marble fragments react with dilute hydrochloric acid to produce carbon dioxide gas. The speed of this reaction can be changed by changing the size of the marble chips. This produces carbon dioxide and calcium chloride.

Learn more about Calcium carbonate here:- https://brainly.com/question/1990063

#SPJ4

Dr. Sweeney observed the end-point of the titration, the chemical equation is HClO4 (aq) + NaOH (aq) → NaClO4 (aq) + H2O (l),  The reaction is a neutralization reaction and the concentration of HCl04 is 0.048 mol/L.

To calculate the concentration of a specified analyte, titration is a typical laboratory technique for quantitative chemical analysis. A reagent, also known as a titrant or titrator, is created as a standard solution with a specified concentration and volume. The goal of the titration is to identify the equivalence point, or the point at which chemically equivalent amounts of the reactants have been combined.

In a chemical reaction called neutralisation reaction, an acid and a base interact quantitatively. In a process in water, neutralisation leads to the absence of excess hydrogen or hydroxide ions in the solution. A neutralisation reaction is a chemical process in which an acid and a base quantitatively combine to produce salt and water as byproducts.

learn more about neutralisation reaction here

https://brainly.com/question/23008798

#SPJ4

95.5 L volume of fluorine gas is produced when 0.427 mol of bromine trifluoride reacts

PV=nRT

p=1 atm

v=?

n=0.427

R= 0.82

T= 273 K

V=nRT/P

V=0.427×0.82×273÷1

V=95.5 L

The volume of an object in three dimensions is the area occupied within its boundaries. It is referred to as the object's capacity on occasion. The amount required to fill an object can be determined by finding its volume, for example, how much water is required to fill a bottle, aquarium, or water tank.

The most fundamental and frequent form of a three-dimensional shape is a sphere. We frequently encounter spheres in the form of balls, globes, decorative lights, oranges, etc.

To know more about  volume  visit :https://brainly.com/question/24189159

#SPJ4

Any substance that moves electrons out of the material is cathode and that moves electron into a material is anode.

Electrochemical reactions is the flow of electric current through electrons between electrodes and electrolyte. The anode is the positive electrode in the reaction and cathode is the negative one.

Conversely, anions and cations are negatively and positively charged ions. Thus, anode contains negative charges which are released into the electrolyte or material. The cathode is positive side which receives those anions from the material. Thus, removing the electron out of material.

Learn more about electrochemical reactions -

https://brainly.com/question/15405355

#SPJ4

As atomic number increases across a horizontal row, the electron configuration of the outermost energy level will become more complex.

This is because each successive element has one additional electron, which will be added to the highest-energy orbital available. As the atomic number increases, more orbitals will become available, which will increase the complexity of the electron configuration in the outermost energy level.

In the modern universe, the behavior of matter is a topic of great interest. The discovery of atomic structure in the mid-19th century changed the way scientists understood the behavior of matter. Atoms contain nuclei and electrons, and the number of the latter is determined by the atomic number.

The atomic number refers to the number of protons present in the nucleus of an atom. This means that the atomic number determines the number of electrons an atom possesses. These electrons are distributed in different energy levels, and the outermost energy level is the last to receive electrons. This means that the atomic number has a direct impact on the electron configuration of the outermost energy level.

Learn more about Atomic Number in the Electronic Configuration:

https://brainly.com/question/17185358

#SPJ4