Determine the empirical and molecular formula of benzene which contains only carbon and hydrogen and is 7.74% hydrogen by mass. The molar mass of benzene is 78.1 g/mol.

Because of its simplicity, comparatively low cost, great sensitivity, and rapid separation, TLC is an extensively used analytical method.

Using a thin stationary phase supported by an inert backing, thin layer chromatography (TLC) is a chromatographic technique used to separate the components of a mixture. It can be carried out on an analytical scale to track the development of a reaction or on a preparative scale to purify minute quantities of a chemical. Similar to all chromatography, TLC works on the premise that a chemical will have varying affinities for the mobile and stationary phases, which will influence how quickly it migrates. TLC aims to produce well-defined, well-separated spots.

Learn more about reaction here-

https://brainly.com/question/28984750

#SPJ4

16.5 g is the mass of sodium chloride that must be dissolved in the same mass of X to produce the same depression at freezing point.

Avogadro's number (6.022 x 1023) of molecules (or formula units) make up one mole of a substance (ionic compound). The mass of 1 mole of a chemical is indicated by its molar mass. It provides you with the number of grams per mole of a substance, to put it another way.

ΔT = Kc*W*i

Kc = cryoscopy constant of the solute X

W = molality of the solution

i = van't Hoff factor, For organic molecules, such as alanine, i = 1.

n = 45.8/89.09

n = 0.5141 mol

W = 0.5141/1.2 = 0.4284 mol/kg

So, Kc of X is:

4.10 = Kc*0.4284*1

Kc = 9.57 °C.kg/mol

So, if now sodium chloride is added to X, and the temperature change is the same, and i = 1.82:

4.10 = 9.57*W*1.82

W = 0.2354 mol/kg

The number of moles of the solute is then:

W = n/1.2

0.2354 = n/1.2

n = 0.2825 mol

The molar mass of sodium chloride is 58.44 g/mol, thus the mass is the molar mass multiplied by the number of moles:

m = 58.44*0.2825

m = 16.5 g

To know more about cryoscopy constant visit:

brainly.com/question/29908903

#SPJ4

When calcium carbonate is heated, it breaks down into the components  calcium oxide and carbon dioxide.

What do you mean by calcium carbonate?

Calcium carbonate is a chemical compound that has the formula CaCO3. It is a common mineral found in rocks as calcite and aragonite, and it is the main component of pearls and the shells of marine organisms, snails, and eggs. Calcium carbonate is a component of agricultural lime that is formed when calcium ions in hard water react with carbonate ions to form limescale. It's commonly used in medicine as a calcium supplement or an antacid, but too much of it can be dangerous.

25 g of calcium carbonate contains 25/100 x (40 + 12 + 3 x 16) = 25/100 x 88 = 22 g of calcium and 12 g of carbon.

Hence, mass of carbon dioxide produced is 12 g.

To know more about calcium carbonate,

https://brainly.com/question/29331980

#SPJ4

Answer:

          i)  Neon (Ne)

           ii)  Fluoride Ion (F⁻¹)

            iii)  Oxide Ion  (O⁻²)

Explanation:

                  Ions are those charged species which are either positively charged (by loosing electrons) called as cations or negatively charged (by gaining electrons) called as anions.

                 In given examples, Neon is a neutral atom which has an atomic number 10. It contains 10 electrons in its neutral state with the electronic configuration 1s², 2s², 2p⁶.

                 Fluorine atom has an atomic number of 9. Therefore, it contains 9 electrons in its neutral state with an electronic configuration of 1s², 2s², 2p⁵. When Fluorine atom gains one electron it gets 10 electrons with electronic configuration of 1s², 2s², 2p⁶.

                Oxygen atom has an atomic number of 8. Therefore, it contains 8 electrons in its neutral state with an electronic configuration of 1s², 2s², 2p⁴. When Oxygen atom gains two electron it gets 10 electrons with electronic configuration of 1s², 2s², 2p⁶ forming an Oxide Ion.

The fourth and fifth periods contain 18 elements rather than 8 as observed in the second and third period because of the accommodation of 10 additional electrons in the 3d orbital.

The number of orbitals that can be accommodated by s subshell is one, p subshell is three, d subshell is five and f subshell is seven.

In the second and the third period, the 2s subshell is filled with two electrons, 2p subshell with six electrons .So, the second period contains eight elements. The sequence in third period is similar to that of second period with additional filling of 3s and 3p subshell.

In the fourth period, electrons are first filled in the 4s subshell, only after that they can be filled in the 3d subshell. So, fourth period contains 18 elements , which is due to the additional 10 electrons in 3d subshell. This is similar in the case of fifth period also.

To know more about fourth and fifth period elements here

https://brainly.com/question/23277752

#SPJ4

Mole measure the number of elementary entities of a given substance that are present in a given sample. Therefore, theoretical yield of Al[tex]_2[/tex]O[tex]_3[/tex] is 136g.

The SI unit of amount of substance in chemistry is mole. The mole is used to measure the quantity or amount of substance. We know one mole of any element contains 6.022×10²³ atoms which is also called Avogadro number. The stoichiometry represents the number of moles.

4AI + 3O[tex]_2[/tex]→ 2Al[tex]_2[/tex]O[tex]_3[/tex]

moles of  Al =54/26=2.07

moles of  O[tex]_2[/tex]=64/32=2

Since oxygen is limiting reagent, so product will be according to oxygen

Theoretical yield of Al[tex]_2[/tex]O[tex]_3[/tex]=136g

Therefore, theoretical yield of Al[tex]_2[/tex]O[tex]_3[/tex] is 136g.

To know more about mole, here:

brainly.com/question/15209553

#SPJ1

Zinc, phosphorus and oxygen are elements contained in dental cement (Zn₃(PO₄)).

Dental cements have a wide range of dental and orthodontic applications. Common uses include temporary tooth restoration, lining cavities to protect the pulp, sedation or isolation, and cementation of fixed prosthetic devices.

A cement-retained bridge is simply a dental device that is permanently fixed in the mouth to restore the mouse's function and aesthetics and to prevent many of the consequences of tooth loss that affect the immediate aftermath of losing natural teeth.

Learn more about prosthetic devices visit:

brainly.com/question/30158376

#SPJ4

As with any laboratory work, adequate facility design, operation, and monitoring, as well as excellent work practices, are necessary to protect laboratory staff against the hazard.

Both degrees of protection are based on the principle of ALARA (as little as reasonably possible) exposure. Electricity Risks By adopting adequate measures, the electrocution dangers of electrically powered instruments, tools, and other equipment are nearly completely minimized, therefore their use in the hazard need not represent a serious risk. You need the correct sort of scales if you want to weigh laboratory samples accurately. To accurately weigh the lab samples, for instance, you may use an analytical balance. The reliability of the weighing device will determine how accurate and precise the findings are.

To learn more about laboratory please click on below link

https://brainly.com/question/14428286

#SPJ4

10.0g of CaBr2 contains 0.05 mol according to the equation mole(n) = mass / molar mass (10.0g CaBr2 x 1 mol CaBr2 / 199.88 g CaBr2 = 0.05 mol)

The mole, represented by the symbol mol, is the SI unit of material quantity. One mole is made up of precisely 6.022*1023 elementary components. The Avogadro number, NA, as expressed in mol1, is the fixed numerical expression of the Avogadro number.

The weight in grams of 1 mole of a certain substance is its molar mass. The atomic mass of the chemical unit, expressed in atomic mass units, determines the mass of a substance (amu).

To know more about mole visit :

https://brainly.com/question/28239680

#SPJ4

The two quantities in this module for which we will develop unit factors to do dimensional analysis with chemical substances are volume and mass.

What is Volume?

Volume is a measure of the amount of three-dimensional space occupied by an object or substance. It is often measured in liters, cubic centimeters, or cubic meters. Volume is used to measure the capacity of a container, the size of an object, or the amount of liquid or gas in a given space. It is also used to determine the mass of an object, as the density (mass per unit volume) is often known.

The two quantities of volume and mass are important for doing dimensional analysis with chemical substances because they help to measure the amount of a substance in different units. Volume is important for measuring the quantity of liquid substances, and mass is important for measuring the quantity of solid substances. Both of these quantities are necessary for accurate and precise measurements of chemical substances, making them essential for dimensional analysis.

To know more about volume,

https://brainly.com/question/14197390

#SPJ4

The fraction of cobalt-60 atoms remaining after 26.5 years is approximately 0.25 (1/4).

An atom is the smallest unit of matter that still retains its properties. It consists of a nucleus, which is made up of protons and neutrons, surrounded by electrons that orbit the nucleus. Atoms are the building blocks of all matter and can combine to form molecules. Atoms are also constantly in motion and can be found in everything from air to rocks. They are essential for life, as they make up all the molecules that form the cells and organs in the human body.

To learn more atom
https://brainly.com/question/6258301
#SPJ4

PBr₃ and Carbon Tetraiodide is a covalent compound. Whereas, KBr and Iron (III) Oxide is an ionic compound.  

Covalent compounds and molecular compounds are those compound where two non-metals, or a non-metal are bonded to each other through the sharing pair of electrons.

PBr₃ are covalent because phosphorous is in the column 3 in periodic system and it has three valence electrons in its outer shell. Therefore, in case of Carbon Tetraiodide carbon and iodide both are non-metals that why they are covalent compounds.

KBr and Iron (III) Oxide both are Iron (III) Oxide because they are formed by the interaction between a metal and non-metal. They will transfer the electrons from positively to negatively charged atoms.

To know more about covalent compound here

https://brainly.com/question/11632372

#SPJ4

Aspartic acid and phenylalanine are the two amino acids that make up aspartame, along with methanol. When the body processes this third key ingredient, formaldehyde and formic acid are produced.

Materials, Raw Two amino acids, phenylalanine and aspartic acid, as well as methanol, make up aspartame. L-aspartyl-L-phenylalanine methyl ester is its formal chemical name. Proteins are made up of amino acids, which are frequently referred to as the building blocks of proteins. Aspartame has the chemical formula C14H18N2O5. In foods and beverages, aspartame, a synthetic, non-saccharide sweetener that is 200 times sweeter than sucrose, is frequently used as a sugar substitute. The commercial names for it are NutraSweet, Equal, and Canderel.

Learn more about aspartame here:

https://brainly.com/question/9352908

#SPJ4

The order of increasing radius is:  Na+ < Rb+ < Br-

The radius of an atom or ion is a measure of the size of the atomic nucleus and the electron cloud that surrounds it. The radius of an atom or ion can be affected by various factors such as the number of protons, neutrons and electrons it has, as well as the electron configuration. In general, as we move from left to right across the periodic table, atomic radius tends to increase.

In the case of the three ions you provided, Br-, Na+ and Rb+ , the order of increasing radius is as follows:

Na+ has the smallest atomic radius among the three, as it has lost one electron and become a positive ion, the removal of the electron increases the effective nuclear charge, making the electron cloud more tightly held.

Rb+ has a slightly larger atomic radius than Na+ as it has one more electron and one more proton in its nucleus than Na+, making the electron cloud slightly less tightly held.

Br- has the largest atomic radius among the three as it has gained an electron and become a negative ion, the addition of the electron decreases the effective nuclear charge, making the electron cloud less tightly held.

Learn more about Radius:

https://brainly.com/question/29440273

#SPJ4

1.53 × 10⁻⁵ moles of aspartame are present in 4.50 mg of aspartame.

Two amino acids, aspartic acid and phenylalanine, make up the low-calorie sweetener known as aspartame. In addition to being present in tabletop sweetener packets, aspartame is a common component used to substitute sugar in low-calorie foods and beverages.

Here there are 4.50 mg of aspartame.

First, the mass is converted from mg to g by:

1 g = 1000 mg

So, 1 mg = 0.001 g

So, 4.5 mg = 4.5 × 10⁻³ g

Molar mass of aspartame = 294.40 g/mol

So, Number of moles of aspartame = [tex]\frac{Given mass}{Molar mass}[/tex]

or, n = 4.5 × 10⁻³ / 294.3

or, n = 1.53 × 10⁻⁵ moles.

Hence, 4.50 mg of aspartame has 1.53 × 10⁻⁵ moles of aspartame.

To know more about aspartame from the link

brainly.com/question/26727229

#SPJ4

The  statement which best explains why the atomic theory developed efficiently is that scientists had used creativity and the scientific method in their investigations regarding the atom.

An atom is defined as the smallest unit of matter which forms an element. Every form of matter whether solid,liquid , gas consists of atoms . Each atom has a nucleus which is composed of protons and neutrons and shells in which the electrons revolve.

The protons are positively charged and neutrons are neutral and hence the nucleus is positively charged. The electrons which revolve around the nucleus are negatively charged and hence the atom as a whole is neutral and stable due to presence of oppositely charged particles.

Learn more about atom,here:

https://brainly.com/question/13654549

#SPJ1

Answer: the answer is B

Explanation: just did it hope it helps

Diatomic elements are elements that exist as two atoms bound together, usually in the form of a molecule.

Diatomic molecules are molecules composed of two atoms, held together by chemical bonds. They are the simplest type of molecule, and are very common in nature. Examples of diatomic molecules include oxygen (O2), nitrogen (N2), hydrogen (H2), chlorine (Cl2), and iodine (I2). Diatomic molecules have a wide range of applications in various industries, such as medicine, chemistry, engineering, and energy.

This differs from other elemental substances because those substances contain only one atom. Diatomic elements are very common in nature and make up a large percentage of the atmosphere. They also have unique properties because of the two atoms being bound together. Diatomic elements are an important part of many everyday processes, from respiration to combustion to corrosion.

To learn more about Diatomic
https://brainly.com/question/1611262
#SPJ4

When we work with a chemical that emits hazardous vapors or fumes, the  best way to protect ourself is by using the fumes hood when working with chemicals.

The best way to protect ourself from the chemical fumes or vapor is the work with chemicals in the fumes hood. the fume hood is the ventilation device that limits the exposure of the hazardous fumes or the vapors.

There are several other ways to protect ourself from the chemical fumes are :

These are the some methods use to protect ourself from the chemical fumes or vapors.

To learn more about chemicals here

https://brainly.com/question/14276888

#SPJ4

Answer: A

Explanation:

Cooling magma becomes more dense and sinks, while hotter magma near the core is less dense and rises, moving magma in a cyclic path.

This answer was obtained from a credible source after doing some research.

The  temperature differences in the layers of Earth move magma as cooling  magma becomes more dense and sinks, while hotter magma near the core is less dense and rises, moving magma in a cyclic path.

Magma is the molten or semi-molten natural material from which all igneous rocks are formed.Magma is found beneath the surface of the Earth, and evidence of magmatism has also been discovered on other terrestrial planets and some natural satellites.Besides molten rock, magma may also contain suspended crystals and gas bubbles.

Magma is produced by melting of the mantle or the crust in various tectonic settings, which on Earth include subduction zones, continental rift zones,mid-ocean ridges and hotspots. Mantle and crustal melts migrate upwards through the crust where they are thought to be stored in magma chambers or trans-crustal crystal-rich mush zones. During magma's storage in the crust, its composition may be modified by fractional crystallization, contamination with crustal melts, magma mixing, and degassing.

Learn more about magma,here:

https://brainly.com/question/16940653

#SPJ2

The enthalpy of the reaction from the bond energy is +102 kJ/mol. Option C

We have to note that the enthalpy would have to do with the energy that ahs been absorbed or the energy that is released in a reaction. We know that if there is a release of energy then we can say that the reaction is exothermic but if we have a case where the energy has been taken in then we can say that the reaction in that case can be said to be exothermic.

We can see that the enthalpy of the reaction can be calculated on the basis of the bond energy when we write;

Energy of bonds that are broken - Energy of bonds that are formed.

[4(410) + 2(496)] - [2(805) + 2(460)]

(1640 + 992) - (1610 + 920)

2632 - 2530

= +102 kJ/mol

Hence, by calculation of the enthalpy bof the reaction, we can see that the reaction would absorb about 102 kJ of heat per mole of the reactant as shown.

Learn more about enthalpy:https://brainly.com/question/13996238

#SPJ1

 Phlogiston theory is wrong as it states that when petrol burns in air phlogiston is lost in  air so the mass decreases but as per law of conservation of mass , mass never increases or decreases rather it is constant.

According to law of conservation of mass, it is evident that mass is neither created nor destroyed rather it is restored at the end of a chemical reaction .

Law needs to be modified in accordance with laws of quantum mechanics under the principle of mass and energy equivalence.This law was proposed by Antoine Lavoisier in the year 1789.

Learn more about law of conservation of mass,here:

https://brainly.com/question/28711001

#SPJ1

one of the BEST actions the US government can take to slow global warming is invest in clean technologies such as wind and solar power

To learn more about global warming refers to:

brainly.com/question/26402403

#SPJ1

Aspartyl-phenylalanine-1-methyl ester, also known as the methyl ester of the dipeptide of the amino acids aspartic acid and the essential amino acid phenylalanine, is the term for an artificial, non-carbohydrate sweetener.

Sweeter than sugar flavoring ingredient that is broken down into phenylalanine and aspartic acid. Aspartyl-phenylalanine-1-methyl ester, also known as the methyl ester of the dipeptide of the amino acids aspartic acid and phenylalanine, is a synthetic, non-carbohydrate sweetener known as aspartame. Aspartic acid is a methyl ester of a dipeptide made up of aspartic acid and phenylalanine, two amino acids. Along with methanol, aspartame is entirely hydrolyzed to its individual amino acids in the digestive system. In the body, aspartame is hydrolyzed into aspartic acid (40%) phenylalanine (50%) and methanol (10%). An amino is aspartic acid.

To learn more about phenylalanine please click on below link

https://brainly.com/question/14951426

#SPJ4

Newton's law of motion that act upon the vehicles at the point of impact is the second law of motion.

Newton's second law of motion states that the force applied to an object is directly proportional to the rate of change of momentum that is produced. Mathematically, we have;

F = m·v - m·u/Δt

Where;

m = The mass of the object

v = The final velocity of the object

u = The initial velocity of the object

Δt = The duration of motion of the object during change in velocity

Therefore, given that the mass, 'M', of the truck is larger than the mass, 'm', of the minivan, where the time of change in velocity Δt, and the initial and final velocities of both automobiles are the same such as in a sudden stop, the garbage ruck will exert more force than the minivan, and therefore, the garbage truck has a greater initial momentum before the automobiles are brought to a stop.

To learn more about momentum check the link below:

https://brainly.com/question/25849204

#SPJ4

The amount of suplher in grams to rpoduce 25.9 kJ energy= 10.95g

Here the reaction is,

S(s) + 2CO(g)  

Hrxn=-75.8 kJ energy.

Answer,

The amount of Sulpher in grams to produce 25.9 kJ energy=  xg=? 

We know that 1mole Sulpher results in the production of \ bigtri angle up Hrxn=75.8 kJ/mol energy.

25.9 kJ of energy produced from how many grams of sulpher= 25.9 kJ / 75.8 kJ/mol = 25.9g/75.8g/mol

                                                                                                                                     =0.34 mol of sulpher

The amount of 0.34 moles of sulpher in grams= Number of moles * Molar mass 

( Molar mss of Sulpher= 32.06g'/mol)

= 0.34mols * 32.06g /mol

=10.95 g

 The amount of suplher in grams to rpoduce 25.9 kJ energy= 10.95g

To know more about energy visit:

https://brainly.com/question/1932868

#SPJ1

Answer:

The last one is true.

The carbon atom is in the center of the structure and is surrounded by four hydrogen atoms.

Structure is an organized arrangement of elements, such as components, materials, people, or ideas. It is a way of organizing and arranging the components of a system in order to achieve a desired outcome.

The most likely Lewis dot structure for methane (CH4) is the following:
The carbon atom is in the center of the structure and is surrounded by four hydrogen atoms. Each hydrogen atom has one electron in its outer shell, and the carbon atom has four electrons in its outer shell. All of the atoms are arranged in a tetrahedral shape, which matches the molecular geometry of methane.

To learn more about structure
https://brainly.com/question/28353159
#SPJ4

The group 17 elements need only one more electron to complete a full octet since they already possess seven valence electrons. whereas group 16 elements needs 2 more electrons that why group 17 more reactive than Group 16

Because they easily acquire an electron to complete their outermost shell, halogens were highly reactive. Since they easily shed the solitary electron in their outermost shell, alkali metals were very reactive.

Since they easily acquire an electron to complete their outermost shell, halogens were highly reactive. Although they easily lose the lone electron within their outermost shell, alkali metals were highly reactive.

Group 17 elements occur only require one electron, therefore they can easily borrow an electron from another element to achieve a stable configuration for a noble gas. They were hence very reactive as well as will rapidly receive an electron to complete their outermost shell.

To know more about halogen elements

https://brainly.com/question/1450671

#SPJ4

Answer:

Explanation:

They are Covalent networks solids