When 2.55g of an unknown weak acid (HA) with a molar mass of 85.0 g/mol is dissolved in 250.0 g of water, the freezing point of the resulting solution is -0.258 Degrees Celsius.
Calculate Ka for the unknown weak acid.

The molarity of the solution is 1.0 m

The first step is to convert the mass of KCl to moles:

Number of moles of KCl = 74.5 g / 74.5 g/mol = 1.0 mol

Next, we need to calculate the mass of water in kilograms:

Mass of water = 1000 mL x 1 L/1000 mL x 1 kg/L = 1 kg

Now we can calculate the molality of the solution:

Molality = moles of solute / mass of solvent (in kg)

Molality = 1.0 mol / 1 kg = 1.0 m

Therefore, the molality of the solution is 1.0 m.

To know more about molarity click here:

brainly.com/question/8732513

#SPJ4

According to the following reaction, 26.1 grams of iodine will react with an excess of hydrogen gas to form 27.4 grams of hydrogen iodide:

2HI(g) + I2(s) → 2H2(g) + 2I(s)

To calculate the number of grams of hydrogen iodide formed, use the following equation:

moles of I2 = 26.1g / 126.90g/mol = 0.205 mol I2

Since there is an excess of hydrogen gas, the number of moles of the hydrogen gas used is equal to the number of moles of I2, which is 0.205 mol.

Number of moles of hydrogen iodide formed = 2 x 0.205 = 0.41 mol

Therefore, the number of grams of hydrogen iodide formed = 0.41 mol x 127.90g/mol = 52.6g

Therefore, 52.6g of hydrogen iodide is formed when 26.1g of iodine reacts with an excess of hydrogen gas.

to know more about chemical reactions refer here:

https://brainly.com/question/29762834#

#SPJ11

The melting point of a substance is the temperature at which the particles have enough kinetic energy to break free from the solid phase and enter the liquid phase.

When the melting point is reached, the solid's lattice structure is disrupted and its particles are free to move, increasing the entropy of the system.

At the molecular level, when particles in a solid gain enough energy, they vibrate more intensely and begin to break the bonds between them. This disruption leads to a decrease in entropy, as the particles move around more freely.

When the melting point is reached, this decrease in entropy is overcome by an increase in entropy due to the particles being able to move around more freely in the liquid state. The disruption of the lattice structure also results in a decrease in the intermolecular forces, and thus a decrease in surface tension.

To know more about lattice structure  click on below link:

https://brainly.com/question/2497050#

#SPJ11

The gas law that is employed to deflate a football is Boyle's law.

Boyle's law states that for a fixed amount of gas at a constant temperature, the pressure and volume of the gas are inversely proportional to each other. The equation for Boyle's law is:

[tex]P_{1} V_{1} /P_{2} V_{2}[/tex]

Where [tex]P_{1}[/tex] is the initial pressure of the gas, [tex]V_{1}[/tex]  is the initial volume of the gas,[tex]P_{2}[/tex] is the final pressure of the gas, and [tex]V_{2[/tex] is the final volume of the gas. In the case of deflating a football, the pressure of the air inside the football is reduced by letting some of the air out. The volume of the football decreases as the pressure decreases, and this is in accordance with Boyle's law.

Therefore, The Boyle's Law is used to deflate a football. It states that the volume of a gas is inversely proportional to its pressure, when the temperature is constant.

To know more about Boyle's law refer here :

https://brainly.com/question/1696010

#SPJ11

Answer:

Boron,silicon,germanium,arsenic,antimony,tellurium, polonium, astatine.

Yes, the chemical basis for a metabolic syndrome is the failure of the body to breakdown fatty acids.

Metabolic syndrome is used to describe a collection of health problems that increase the risk of developing other diseases such as diabetes, heart disease, and stroke. The primary cause of metabolic syndrome is obesity, which is why it is frequently referred to as "obesity syndrome."

The syndrome is also linked to other genetic and environmental factors that contribute to insulin resistance, inflammation, and high blood pressure, as well as a failure to break down fatty acids properly in the body. Thus, the chemical basis for metabolic syndrome is the failure to break down the fatty acids in body. This chemical problem can contribute to the development of other fatal diseases and health problems.

Learn more about Metabolic syndrome here:

https://brainly.com/question/31106238

#SPJ11

The volume of the ammonia that can be produced from the reaction that has been written is;  155 * 10^7 L

We know that;

PV = nRT

For the hydrogen;

n = PV/RT

n = 155 * 4.0 x 10^7 /0.082 * 776

n = 620 * 10^7/63.63

n = 9.7 * 10^7 moles

Now the reaction equation is;

N₂(g) + 3H₂(g) → 2NH3(g)

3 moles of hydrogen  produced 2 moles of ammonia

9.7 * 10^7 moles will produce  9.7 * 10^7 moles * 2 moles/ 3 moles

x = 6.5 * 10^7 moles

For the volume of the ammonia;

V = nRT/P

V =  6.5 * 10^7 moles * 0.082 * 293.6/1.007

V = 155 * 10^7 L

Learn more about ammonia:https://brainly.com/question/14672082

#SPJ1

1. The balanced chemical equation shows that for every 2 molecules of octane burned, 16 molecules of carbon dioxide are produced. Therefore, the number of molecules of carbon dioxide represented by the equation is 16.

2. The balanced chemical equation shows that for every 2 molecules of octane burned, 25 molecules of oxygen are required. Therefore, the ratio of octane to oxygen is 2:25. From this, we can determine the number of moles of octane represented by the equation by dividing the given amount of oxygen by the ratio:

25 mol O2 × (2 mol C8H18 / 25 mol O2) = 2 mol C8H18

Therefore, the equation represents 2 moles of octane.

3. The simplified mole ratio of octane to carbon dioxide can be determined by dividing both sides of the equation by the coefficient of octane (2):

2C8H18(g) +25O2(g) → 16CO2(g) + 18H2O(l)

Dividing by 2, we get:

C8H18(g) + 12.5O2(g) → 8CO2(g) + 9H2O(l)

The simplified mole ratio of octane to carbon dioxide is therefore 1:8.

4. The simplified mole ratio of oxygen to octane can be determined in the same way, by dividing both sides of the equation by the coefficient of octane:

2C8H18(g) +25O2(g) → 16CO2(g) + 18H2O(l)

Dividing by 2, we get:

C8H18(g) + 12.5O2(g) → 8CO2(g) + 9H2O(l)

The simplified mole ratio of oxygen to octane is therefore 12.5:1.

Learn more about octane here https://brainly.com/question/29657423

#SPJ1

Yes, this is a good idea as it is an efficient use of resources. Advantages include reduced costs of purchasing new drying agents and decreased wastage of materials. Disadvantages could include loss of quality of the recycled drying agent, and extra energy used to dry out the salt.

Drying agents can be collected after an experiment and the hydrated salt heated in an oven to drive off the water. The recycled drying agent can then be used again for another experiment.

What are drying agents?

In order to absorb water vapor, drying agents are added to organic solvents to make them anhydrous.

What are the advantages and disadvantages of recycling drying agents?

The recycling of drying agents has a few advantages and disadvantages:

Advantages of recycling drying agents:

Cost-effective: If the solvent used is expensive, recycling drying agents can save money. A drying agent like anhydrous magnesium sulfate is a good example since it can be reused numerous times. No pollution: The disposal of waste is reduced. If every time a new drying agent is employed, it must be disposed of properly, which is both time-consuming and costly. The amount of waste that has to be disposed of is reduced if the same drying agent is used repeatedly. Recyclable waste: Used drying agents are recyclable. It's just a matter of heating the salt to remove any water and returning it to the drying agent stock. This procedure helps to prevent waste.

Disadvantages of recycling drying agents:

Contamination: Even though the recycled drying agent is supposed to be pure, it may still contain minor quantities of impurities, which might result in contamination of the final product. Impurities: If the drying agent is not cleaned properly, impurities will be transferred from one experiment to the next. Excessive heating: Anhydrous drying agents should not be heated excessively because they may lose their effectiveness. If the salt is heated for too long, the surface area exposed to moisture will be decreased. Therefore, while recycling drying agents is a good idea, some precautions should be taken to ensure that the drying agent is pure and effective.

For more details follow the link: https://brainly.com/question/30712002

#SPJ11

The partial pressure of oxygen in the atmosphere is 0.210 atm.

Therefore, the partial pressure of oxygen in mm Hg is 0.210 atm x 760 = 158.6 mm Hg and the partial pressure of oxygen in torr is 0.210 atm x 760/101.325 = 1.55 torr.

The air in the atmosphere is composed of many different gases. The most common of these gases is nitrogen, which makes up 78% of the atmosphere.

Oxygen makes up 21% of the atmosphere, and the other gases make up 1%. The atmospheric pressure is the pressure created by the weight of the gases in the atmosphere.

The atmospheric pressure is measured in units of atmospheres (atm). The atmospheric pressure at sea level is usually around 1 atm, which is equal to 760 mm Hg and 101.325 torr.

This is the same pressure that you feel when you take a breath of air.

The partial pressure of a gas is the amount of pressure exerted by that gas alone, as opposed to the total atmospheric pressure. The partial pressure of oxygen in the atmosphere is 0.210 atm.

This means that, out of the total atmospheric pressure of 1 atm, 0.210 atm of the pressure is from oxygen.

Partial pressure is often measured in units of mm Hg or torr. To convert from atm to mm Hg, the value is multiplied by 760.

Therefore, the partial pressure of oxygen in mm Hg is 0.210 atm x 760 = 158.6 mm Hg and the partial pressure of oxygen in torr is 0.210 atm x 760/101.325 = 1.55 torr.

to know more about partial pressure refer here:

https://brainly.com/question/13199169#

#SPJ11

The statement "the percent ionization of a weak acid in water increases as the concentration of acid decreases" is CORRECT.

It happens because of Le Chatelier's principle which states that a system at equilibrium will respond to any external changes to oppose the changes and re-establish the equilibrium. A weak acid in water is in equilibrium with its ions as follows:

  HA (aq) + H2O (l) ⇌ H3O+ (aq) + A- (aq)

Where HA is the weak acid and A- is its conjugate base.

The extent of ionization or dissociation of the weak acid is measured by its degree of ionization which is expressed as a percentage. It can be calculated as:

Degree of ionization = (amount of HA ionized / initial concentration of HA) × 100

As per the statement, if the concentration of the weak acid is decreased, the system is no longer at equilibrium as the amount of HA will decrease. According to Le Chatelier's principle, the system will shift towards the side with more HA molecules to restore equilibrium. This will result in more dissociation or ionization of HA to form H3O+ and A-. Hence, the degree of ionization or percent ionization of the weak acid will increase with a decrease in the concentration of the acid.

Learn more about Le Chatelier's principle at https://brainly.com/question/2943338

#SPJ11

The model for the atom that was understood when Bohr made his contributions were called the option (A) Planetary Model.

Bohr's model, also known as the Planetary model, is a basic model of the atom that explains the atomic structure. The atomic nucleus is in the center of the atom, with electrons moving in circular orbits about it at different energy levels.

The model is called the planetary model because it resembles the planets in the solar system revolving around the sun. The electrons are arranged in concentric circles around the nucleus, with each circle corresponding to a specific energy level.

In summary, when Bohr made his contributions, the model for the atom that was understood was called the Planetary Model.

To know more about the planetary model:

https://brainly.com/question/30790603

#SPJ11

Answer: carbon and hydrogen 

Explanation:

Hydrocarbons are a group of chemical organic compounds composed of carbon and hydrogen 

notable states in the United States where gold is found include California, Alaska, Colorado, Nevada, and South Dakota.

when:(gold rushes)

   California (1848-1855)

   Colorado (1858-1861)

   Alaska (1896-1899)

   South Dakota (1874-1877)

   Georgia (1828-1849)

   Montana (1862-1864)

   Nevada (1859-1864)

   Oregon (1851-1861)

   North Carolina (1799-1848)

The correct option is A. "more; less; greater; higher".

Explanation: Intermolecular forces refer to the forces of attraction and repulsion between molecules. These forces determine the physical properties of a substance, such as melting point, boiling point, and solubility.

A molecular substance with strong intermolecular forces means that the molecules are held tightly together, which requires more energy to overcome to break the bond.

The molecules at the surface of the liquid are held more tightly and vaporize less easily than molecules with weaker intermolecular forces. Molecules with weaker intermolecular forces are more likely to escape from the surface of the liquid and form the vapor phase.

Therefore, the amount of substance in the vapor phase will be less for molecules with strong intermolecular forces.

The vapor pressure is the pressure exerted by the vapor phase of a substance in equilibrium with its liquid or solid phase. The vapor pressure increases as the temperature increases or the amount of substance in the vapor phase increases.

Since the amount of substance in the vapor phase is less for molecules with strong intermolecular forces, the vapor pressure will be greater for molecules with weaker intermolecular forces.

to know more about force refer here

https://brainly.com/question/13191643#

#SPJ11

If a molecular substance has strong intermolecular forces, the molecules at the surface of the liquid are held less tightly and vaporize more easily than molecules with weaker intermolecular forces. The amount of substance in the vapor phase will be greater than for molecules with weak intermolecular forces and the vapor pressure will therefore be higher.The correct answer is b.

Molecules are held together by the force of attraction between the atoms in them, but there are also forces between the molecules. These forces are called intermolecular forces. For example, the intermolecular forces that exist between water molecules are hydrogen bonding, while the intermolecular forces between propane molecules are van der Waals forces.

The boiling point of a liquid is determined by the strength of the intermolecular forces between the molecules that make up the liquid. The stronger the intermolecular forces, the higher the boiling point.

Learn more about intermolecular forces here:

brainly.com/question/9328418

#SMJ11

The balanced chemical equation for the decomposition of solid Mercury (II) oxide (HgO) into liquid Mercury and gaseous Dioxygen is:

[tex]HgO (s) \rightarrow Hg (l) + O_2 (g)[/tex]

Mercury (II) oxide, HgO, is a stable compound that may be decomposed by heating it to generate mercury metal and oxygen gas.

This reaction may be classified as a thermic decomposition reaction because it is initiated by heat. The equation is balanced as there is one atom of mercury on the left-hand side and one on the right-hand side.

Similarly, there are two atoms of oxygen on the left-hand side and two on the right-hand side. The physical state of HgO is solid, whereas the physical state of Hg and [tex]O_2[/tex] is liquid and gaseous, respectively.

To learn more about balanced chemical equation refer - https://brainly.com/question/14228953

#SPJ11

Saddam Hussein's overthrow in 2003 was one of the early results of regime transition in Iraq. Given that Hussein had been in charge of Iraq's government and society for more than 20 years,

this represented a dramatic change in the political landscape of the nation. Regime transition, however, was followed by a turbulent era of political unrest and sectarian warfare. Broader geopolitical repercussions of the US-led invasion of Iraq and subsequent government change included strained ties with other nations in the region, a rise in anti-American sentiment, and the creation of new extremist organizations like ISIS. The long-term implications of the Iraqi government transition are still being discussed and examined, although is clear that the initial outcome was one of significant.

learn more about Iraq  here:

https://brainly.com/question/29605758

#SPJ4

Based on the information provided, the correct answer is:

Substance R changed phase because the weak attraction between molecules let them move faster. Its molecules now move around each other.

This is because when the scientist transferred the same amount of energy out of both substances, only one substance changed phase while the other did not. This indicates that one of the substances has a lower boiling point than the other. Since both substances are liquids at room temperature, it means that the substance that changed phase must have vaporized (turned into gas) while the other substance did not.

Substance R must have a weaker intermolecular force of attraction between its molecules compared to Substance Q. This means that Substance R has a lower boiling point, which allowed its molecules to move around each other and form a gas phase when energy was transferred out of it. In contrast, Substance Q remained in the liquid phase because its molecules had stronger intermolecular forces of attraction that held them together.

To know more about Molecules, visit: brainly.com/question/19922822

#SPJ4

The stereocenter-containing molecule is:

1,2-dimethylcyclohexane (both carbons at position 1 and 2 are stereocenters as they have four distinct substituents connected to them)

(both carbons at position 1 and 2 are stereocenters as they have four different substituents attached to them)

Stereocenters are absent from the other compounds that were listed. Because the double bond does not include any substituents that are distinct from one another, the alkene with H wedges and the CH3 dash does not have stereocenters. As all of the carbons in cyclohexane are symmetric and do not have four separate substituents connected to them, the cyclohexane with wedge-dash methyl likewise lacks stereocenters., the only molecule in the list that contains stereocenters is 1,2-dimethylcyclohexane.

learn more about stereocenter-containing here:

https://brainly.com/question/23096013

#SPJ4

Isotopes are different forms of an element that have different atomic masses. The number of protons in each atom of an element will remain the same, but isotopes of an element will have different numbers of neutrons, leading to different atomic masses.

Isotopes are different forms of an element that have different numbers of neutrons in their nuclei. The number of neutrons in an atom can vary from one to several, depending on the element. Isotopes are atoms of an element that differ in the number of neutrons present in their nucleus. The atomic number of an element is determined by the number of protons present in the nucleus. However, the isotopes of the same element differ in their mass numbers. The atomic mass of an element is determined by the number of protons and neutrons present in the nucleus.

The atomic number of an atom is the sum of the number of protons in the nucleus and the number of electrons in a neutral (non-ionized) atom. Each atomic number designates a particular element, but not an isotope; the number of neutrons in an atom of a given element can vary widely. Each isotope of an element has a particular mass number, which is determined by the number of nucleons (both protons and neutrons) in the nucleus. Therefore, the isotopes of an element have different atomic masses.

Isotopes can be radioactive or stable, depending on the number of neutrons present in the nucleus. For instance, carbon-14 is a radioactive isotope of carbon, while carbon-12 is a stable isotope.

For more such questions on Isotopes , Visit:

https://brainly.com/question/14220416

#SPJ11

1. The approximate bond angle for a molecule with an octahedral shape  is 90 degree. so, option (e) is correct.

2. The hybridization of the orbitals on carbon in C2H4 is SP2 hybridization.

The octahedral shape of molecules is defined as the shape of molecules where six atoms or ligands or groups of atoms are arranged in a systematic way around a central dogma or atom. The Octahedral Shape of Molecules contains eight faces and the band angel is 90 degree. It consists of two square pyramids back to back each square pyramid with four faces.

In sp² hybridization is defined as the hybridization where one s orbital and two p orbitals hybridize to form three sp² orbitals each of this consisting of 33% s character and 67% p character. SP2 hybridization is required whenever an atom is surrounded by three groups of electrons.

To learn more about octahedral shape

https://brainly.com/question/30160815

#SPJ4

The complete question is,

1. Give the approximate bond angle for a molecule with an octahedral shape.

a. 109.5°

b. 180°

c. 120

d. 105°

e. 90°

2. What is the hybridization of the orbitals on carbon in C2H4?

Interference can be solely explained by considering the wave nature of light. Therefore, option C is correct.

Interference is a phenomenon that occurs when two or more waves interact with each other. It can be observed in various contexts, including light waves. When two light waves meet, they can either reinforce each other or cancel each other out , depending on their relative phases.

Reflection and refraction can be explained by considering both the particle and wave nature of light. Reflection occurs when light waves bounce off a surface, while refraction refers to the bending of light as it passes from one medium to another.

To learn more about the Interference, follow the link:

https://brainly.com/question/31857527

#SPJ12

The substrate below is primary and will undergo an [tex]SN^2[/tex] reaction when treated with a strong nucleophile. The correct answer is b. primary: will.

Learn more about substitution nucleophilic bimolecular reaction: https://brainly.com/question/30631335

#SPJ11

1.  0. 0728 mole to Silicon is equals to 2.044 gram.

2. 5. 5mol of H2O is equals to 99.08 gram.

3. 0. 0728 of Ca(H2PO4)2 is equals to 17.038 gram.

The Moles can be converted to mass in grams by multiplying the molecular weight by the number of moles for the substance. The molecular weight is defined as the number of grams per mole for the substance and gives the conversion factor for moles to grams for that particular substance.

The molecular weight is defined as the mass of a given molecule: it is measured in grams per mole. According to Dalton's different molecules of the same compound may have different molecular masses because they contain different isotopes of an element.  

1. 0.0728 mole of silicon.

  The molecular weight of silicon is 28.09 g/mole.

 =  0.0728 mole * 28.09 g/mole

 = 2.044 gram.

2.  5. 5mol of H2O

    The molecular weight of water is 18.01528 g/mole.

   =  5. 5mole * 18.01528 g/mole

   = 99.08 gram

3.  0. 0728 of Ca(H2PO4)2

    Molecular weight of  Ca(H2PO4)2 is 234.05 g/mole.

    = 0. 0728mole * 234.05 g/mole

    = 17.038 gram

To learn more about moles

https://brainly.com/question/13314627

#SPJ4

The order of increasing reaction rate of alkyl halides with triethylamine is iodoethane, 1-bromopropane, and 2-bromopropane.

When the primary alkyl halide reacts with the triethylamine, it's faster than the secondary alkyl halide. Since triethylamine is a strong, bulky base that tends to perform nucleophilic substitution, it undergoes a reaction with both primary and secondary alkyl halides. When halides react with triethylamine, the bond between nitrogen and carbon is formed.

In this reaction, the rate of reaction will be slower with secondary alkyl halides due to steric hindrance.  Iodoethane will be more reactive than 1-bromopropane because of the higher electronegativity of iodine which makes it more prone to nucleophilic substitution. Based on the above discussion, the order of increasing rate of reaction with triethylamine is 2-bromopropane < 1-bromopropane < iodoethane.

Therefore, iodoethane is the most reactive of the three alkyl halides, 1-bromopropane is more reactive than  2-bromopropane and 2-bromopropane is the least reactive.

To know more about alkyl halides, refer here:

https://brainly.com/question/17063582#

#SPJ11

The electrons donated to the electron transport chain by NADH activate 4 proton pumps, while those donated by FADH2 activate 2 proton pumps. Electron transport is the process by which electrons are passed from one molecule, such as NADH or FADH2, to another molecule, such as oxygen.

The electrons donated to the electron transport chain by NADH activate 10 proton pumps, while those donated by FADH2 activate 6 proton pumps.

What is the electron transport chain?

The electron transport chain (ETC) is a chain of molecules that move electrons down a gradient from a higher energy state to a lower energy state, releasing energy along the way. In eukaryotic cells, the electron transport chain is located in the inner mitochondrial membrane. Electrons from NADH and FADH2 are passed down the chain in the electron transport chain, which eventually generates a proton gradient used to create ATP. In the electron transport chain, NADH and FADH2 donate electrons to a chain of electron carriers, which then pump protons from the mitochondrial matrix to the intermembrane space. The number of proton pumps activated by electrons donated by NADH and FADH2 differ. Electrons donated by NADH activate ten proton pumps, while electrons donated by FADH2 activate six proton pumps. The electron transport chain is responsible for the generation of the proton motive force used by ATP synthase to create ATP, which is the main source of energy for the cell.

To know more about electron transport chain, click the below link:

https://brainly.com/question/24372542

#SPJ11

By supplying more energy to counteract intermolecular interactions and increasing contact between solvent and solute, raising temperature, agitation, surface area, or lowering particle size can enhance solubility.

A substance's solubility refers to its capacity to dissolve in a solvent. Intermolecular forces between the solute particles are broken during the dissolving process, and new connections with the solvent molecules are created. Solubility can be raised by adding extra energy to break through these intermolecular connections. Although agitation and expanding surface area improve the contact between the solvent and solute, rising temperature releases more thermal energy to break the intermolecular interactions. By increasing surface area per unit volume, particle size reduction increases interaction with the solvent. Moreover, by giving the solute additional solvation sites, more solvents or surfactants can be added to increase solubility.

learn more about solubility here:

https://brainly.com/question/29857840

#SPJ4

Structural formula: Definition: A structural formula is a molecular representation that depicts the relationship between atoms or functional groups in a chemical compound. It's also known as a chemical formula or molecular formula.

Structural formulas provide a more detailed view of the molecular structure than empirical formulas, which only show the simplest ratio of atoms in a compound.

The structural formula also shows the spatial arrangement of atoms and groups in a compound.

There are two types of structural formulas: condensed structural formulas and Lewis structures.

Condensed structural formulas provide a concise representation of the molecular structure by eliminating most of the bonds and functional groups present in a compound.

The Lewis structure, on the other hand, shows the bonding pairs and lone pairs of electrons present in a molecule.

Structural formulas are critical in chemical analysis, particularly in organic chemistry, where they aid in the identification and characterization of chemical compounds.

These formulas help to explain the chemical properties and behavior of compounds, making them useful in drug development, food production, and other industries.

For similar question on structural formula.

https://brainly.com/question/26388921

#SPJ11

Answer:

The balanced chemical equation for the reaction is:

C + 2H2 → CH4

From the equation, we can see that 1 mole of carbon reacts with 2 moles of hydrogen to produce 1 mole of methane. Therefore, to produce 7.8 moles of methane, we would need:

1 mole of carbon = 1 mole of CH4 / 2 moles of H2 = 1/2 mole of CH4

7.8 moles of CH4 = 7.8 × (1/2) moles of C = 3.9 moles of C

Now, we can use the molar mass of carbon to convert moles to grams:

Atomic mass of carbon (C) = 12.01 g/mol

3.9 moles of C × 12.01 g/mol = 46.8 g of C

Therefore, we need 46.8 grams of carbon to produce 7.8 moles of methane (CH4). Rounded to the nearest tenth, the answer is 46.8 grams.

Titration is the best investigation to identify an unknown liquid as acidic, basic, or neutral by measuring its pH level.

A student finds an unlabeled bottle of liquid under his kitchen sink. Titration is the investigation that would best help him identify the unknown liquid as acidic, basic, or neutral.

Titration is the chemical method used to find the amount of acid or base in a given substance. This method is a laboratory technique used to measure the concentration of a known solution (the titrant) with a solution of an unknown concentration (the analyte).

The unknown solution is slowly added to the known solution until it reacts completely, allowing us to calculate the concentration of the unknown solution. Titration may be used to identify an unknown solution as acidic, neutral, or basic by determining its pH level. It's a highly precise technique that's often used in analytical chemistry laboratories to measure the concentration of chemicals.

Learn more about liquid: https://brainly.com/question/1313076

#SPJ11