Which of the following are exact
numbers? Select all that apply.

The given statement is true since the number of objects in a mole is dictated by a quantity called Avogadro's number.

Avogadro's number is quite an important quantity in chemistry as well as other branches of science. It tells us how many atoms are there in one gram atom of a compound, how many molecules are there in one gram molecule of a compound, and how many ions are there in one gram of ions in a substance.

It was discovered by the Italian scientist Amedeo Avogadro and thus, named after him. Its value is = 6 . 022 × 10²³ mol⁺¹ and its SI unit are the reciprocal of a mol (mol⁺¹). Hence, the given statement is indeed true.

Learn more about Moles on

https://brainly.com/question/26416088?referrer=searchResults

#SPJ4

K2CO3 + 2HNO3 = 2KNO3 + H2CO3. The necessary quantity of n (KNO3)    is equal to 2 x n (H2CO3), or 2 x 0.228, or 0.456 mol. This exceeds the amount that is accessible (0.15 mol). KNO3 is the least reactive as a result.

What does the word reactive mean?

reacting to circumstances or events rather than taking proactive measures to influence or prevent them: Unfortunately, rather than taking a proactive approach to the issue of auto theft, the police have taken a reactive one. They only seem to be capable of responding adversely to proposals made by other individuals.

Which of the following describes a reactive chemical?

Explosives, peroxides, water-reactive substances, and pyrophorics are a few examples of extremely reactive chemicals.

To know more about reactive visit:

https://brainly.com/question/1598581

#SPJ1

When opposed to humid areas,  ground water will be deeper in arid areas. underground water source termed an confined aquifer is one in which an impermeable layer blocks the water's path to the surface the planet.

An aquifer that has restricting beds enclosing it on both the top and bottom is said to be confined. At substantial depths below the surface of the ground, confined aquifers typically exist.

Aquifers that are enclosed and filled with water are those that are found beneath the surface of the land. The aquifer is under pressure because of the impermeable layers that are both before and below it. As a result, when a well drills into the aquifer, water will rise over the top of the impermeable layers.

To know more about confined aquifers visit:

https://brainly.com/question/14916917

#SPJ4

Answer 1

The average atomic mass in a.m.u of Element X given this information is 122.358.

Answer 2

Rutherford's experiment change the way scientists had previously viewed atomic structure as it provided insight into atomic structure.

Rutherford's experiment paved the way for subsequent changes up to and including the currently accepted quantum mechanical atomic model as his  model of the atom, the structure of the nucleus became more well-defined following the discovery of protons (1919) and neutrons (1932) as the particle constituents of the nucleus.

Answer 3

The percent abundance is related to the number fraction as fi = Pi/100  and used as in the formula written above in order to find average mass

Atomic structure refers to the structure of an atom comprising a nucleus (centre) in which the protons (positively charged) and neutrons (neutral) are present.

The average atomic mass in a.m.u of Element X given this information is ((121 * 43.2) + (123 * 53.1) + (129 * 3.70)) / 100

=5227.2 + 6531.3 + 477.3

=12235.8 / 100

122.358

Rutherford's experiment change the way scientists had previously viewed atomic structure as it provided insight into atomic structure, and Rutherford's model of the atom was proposed as a small, positive, massive nucleus contains the very vast majority of the mass of the entire atom with negatively charged electrons surrounding it at relatively large distances.

Rutherford's experiment paved the way for subsequent changes up to and including the currently accepted quantum mechanical atomic model as his  model of the atom, the structure of the nucleus became more well-defined following the discovery of protons in 1919 and neutrons in 1932 as the particle constituents of the nucleus.

It was during the 1920s that a "wave mechanical model" came along through the work of several physicists most importantly de Broglie, Heisenberg, and Schrodinger) and Bohr's concept of electrons "orbiting" the nucleus was abandoned in favor of "orbitals" which are more abstract probabilistic representations of electronic structure within an atom.

Learn more about atomic structure at: https://brainly.com/question/25653224

#SPJ1

Based on the given information, the area that is most likely to have more chemical weathering is Area 1.

What is chemical weathering?

To learn more about chemical weathering refer to:

https://brainly.com/question/29784355

#SPJ4

Answer: Option b is correcr

Explanation: ption A: The relevant solubility rule is: Compounds with halides are soluble except when with silver, lead, or mercury. Therefore the products of this reaction are all soluble and the reaction will not occur as no precipitate is made.

Option B: In addition to the solubility rule stated in Question A, all nitrates are soluble. Therefore the products of this reaction are all soluble and the reaction will not occur as no precipitate is made.

Option C: Based on the solubility rules already mentioned, the products of this reaction are all soluble and the reaction will not occur as no precipitate is made.

Option D: Most compounds of phosphate are insoluble with exceptions being with ammonium and some Group 1A metals. Based on this, the silver phosphate

Ag will be insoluble and form a precipitate. Therefore this reaction will occur and Option D is the correct answer

To know more about reactions,

brainly.com/question/28260925

brainly.com/question/11033032

Formula

[tex]\ell=\frac{n h}{2 \pi}[/tex]

[tex]\ell = angular \: momentum[/tex]

[tex]n = principal quantum number \\ h = Planck's constant \\ \pi = pi[/tex]

The given question is 98, 99, 100 , 90, 98 , 100

Mean= [tex]\frac{Sum of observations}{Number of observations}[/tex]

In mathematics and statistics, the average is the average of a set of values. The mean can be calculated in a number of ways, including the simple arithmetic mean (adding the numbers and dividing the sum by the number of observations), the geometric mean, or the harmonic mean.

Sum of observations is 98+99+100+90+98+100

The summation is 585

The number of observations is 6.

= [tex]\frac{98+99+100+90+98+100}{6}[/tex]

= 97.5

So, the answer is 97.5

A popular science project and craft used to better understand how particular atoms function is the creation of 3D atom models. When teaching about atoms, a 3D atom model can be used to demonstrate concepts in a classroom or to provide explanations.

The 3D concept of the atom and how the protons and neutrons in the nucleus relate geometrically and in terms of size to the electrons spaced at relatively great distances from the nucleus can be introduced to students from elementary school through high school through an atom model project.

It should be noted that in order to make the 3D concept for the model, attach eight small craft balls to the medium circle, eight to the large circle, eight to the extra-large circle, and finally two to the small circle with glue. These will resemble each and every atom's electron. To help the model hang, attach a piece of string to the outer circle.

Learn more about atom on:

https://brainly.com/question/17545314

#SPJ1

Answer:

Explanation:

O2 gives your brain oxygen H2O Hydrates your body

The percentage yield of the reaction from the given parameters would be 30.99%. Option B.

The percent yield of a reaction is the actual amount of product formed relative to the theoretical amount of product that is supposed to be formed from the same reaction.

This is mathematically expressed as:

Percent yield = actual yield/theoretical yield x 100%

In this case: the actual yield = 16.81 g, the theoretical yield = 54.25 g

Thus, the percent yield of the reaction can be calculated as:

16.81/54.25 x 100% = 30.99%

In other words, the percent yield of the reaction would be 30.99%.

More on percent yield can be found here: https://brainly.com/question/12704041

#SPJ1

Answer: B. 30.99%

Explanation:

The molarity of the solution produced when the 145 g of sodium chloride (NaCI) is dissolved in the sufficient water to prepare the 2.75 L of solution is 0.90 M.

Given that :

Mass of the sodium chloride NaCl = 145 g

Volume of the NaCl = 2.75 L

The molar mass of the NaCl = 58.4 g/mol

The moles is given as :

Moles = mass / molar mass

Moles = 145 / 58.4

Moles = 2.48 mol

The molarity expression is given as :

Molarity = moles / volume in L

Molarity = 2.48 / 2.75

Molarity = 0.90 M

Thus, the molarity of KCl is 0.90 M.

To learn more about molarity here

https://brainly.com/question/8732513

#SPJ4

The result of DNA replication identical is two DNA molecules consisting of one new nucleotide chain and one old chain.

DNA replication is a process of doubling the DNA chain assisted by DNA polymerase enzymes in the interphase before mitosis. Prokaryotes carry out continuous DNA replication and eukaryotes carry out DNA replication in the S phase of the cell cycle before mitosis. DNA replication aims to produce new DNA that is identical to the parent cell's DNA so that DNA replication is described as semi-conservative.

The semi-conservative theory resulted in two DNA strands consisting of one old strand and one new double helix with exactly the same information as the old DNA. The result of DNA replication is two DNA molecules consisting of one new nucleotide chain and one old chain. That is why the results of DNA replication have the same or identical properties.

Learn more about semi-conservative  at:

https://brainly.com/question/2114471

#SPJ4

Answer:

Explanation: you have to divide the simbles

Answer:

something that is impossible

The conversion of the following moles to grams is as follows:

The number of moles of a substance can be converted to mass using the following formula:

moles = mass ÷ molar mass

According to this question, 0.989 moles of phosphorus and 1.21 moles of carbon dioxide is given. The mass can be calculated as follows:

mass of phosphorus = 31 × 0.989 = 30.659g

mass of carbondioxide = 44 × 1.21 = 53.24g

Learn more about mass at: https://brainly.com/question/21042927

#SPJ1

1) anhydride normal peaks (1760 and 1810 cm-1) there are two peaks for anhydrides at the above freq. our peaks are at 1759 cm-1 and one at 1838 cm-1 (cyclic anhydride 5 membered ring again increases freq. upto 30 cm-1).

So, the peak at 1838 cm-1. electronegetive oxygen atom (inductive effect) between two carbonyl group increases the freq, while resonanse lowers the freq.

2) While cracking the dimer it will give us monomer which then reacts with maleic anhydride to give Diels-Alder product, it does not give any unwanted product at higher temperature. if cracked monomer reacted at low temp. or it does not reacted immediately with maleic anhydride then unwanted product will be obtained

3) breaking the dimer at high temperature and it is to be reacted immediately can isolate the pure prodict.

To know more about anhydride here

https://brainly.com/question/28148464

#SPJ4

Temperature. The desert reaches an average daily temperature of 38°C (just over 100°F). Desert nighttime temperatures typically drop below -3.9°C (approximately 25°F).

What is the desert's highest temperature?

The world's hottest air temperature was recorded at Death Valley: A scorching 56.7°C (134.1°F) was recorded on July 10, 1913, in the California desert's aptly called Furnace Creek location. Meanwhile, the average summer temperature frequently exceeds 45°C (113°F).

What is the desert's lowest temperature?

Desert surfaces lose nearly twice the same or more heat at night as humid ones do and receive slightly more than twice as much solar energy. Many average annual temperatures fall between 20 and 25 °C. The extreme maximum temperature is between 43.5 and 49 degrees Celsius. At times, the minimum temperature falls below -18 degrees Celsius.

To know more about temperature visit:

https://brainly.com/question/23411503

#SPJ1

The internal energy change of the reaction is -561J, and w for the species is +235J according to the provided statement.

In a chemical reaction, one or more substances—also known as reactants—are changed into one or more additional compounds are known as products. Chemical elements or chemical compounds make up substances.

Using the basic principle of thermodynamics,

ΔE = q + w

Q is -ve when heat is produced.

Thus,

q = - 495 J

ΔE = -31J

These variables are substituted in the equation above to yield,

- 31 J = - 495 J + w

or, w = +464 J

Using the basic principle of thermodynamics,

ΔE = q + w

Q is -ve when heat is produced.

Thus,

q = -796 J

The system has been worked on, thus w is positive.

Thus,

w = +235 J

These variables are substituted in the equation above to yield,

ΔE = + 235 J - 796 J

ΔE = -561 J

To know more about Reaction visit:

brainly.com/question/25769000

#SPJ4

The complete question is-

A chemical reaction is run in which 495 Joules of heat are generated and the internal energy changes by -31 Joules.

Calculate 'w' for the system in (Joules)

A chemical reaction is run in which 796 Joules of heat are generated and 235 Joules of work are done on the system.

Calculate the change in the internal energy of the chemical system.

ΔE in Joules

The correct option c. nonmetals. Nonmetals make up the majority of the elements of groups 16 through 18.

The position of an element on this periodic table has a significant impact on how that element is defined.

Elements of groups 16 through 18:

To know more about the elements, here

https://brainly.com/question/10753686

#SPJ1

                                                                               ··                               ··  

The balanced equation was found to be Na· + ·Cl : ---------> Na + (: cl : )-

                                                                               ..                               ..          

Define ionic bond dot diagram ?

Group 8 elements, generally known as noble gases, are noted for their inertness. They hardly never react with other elements, such as water, oxygen, or metals. This is due to the fact that they all have a complete outer shell of electrons. This is the most stable electron configuration possible for an atom.

Other elements, on the other hand, do not have this stable electron configuration. Instead, in order to obtain that ideal arrangement, they must acquire, lose, or share electrons. Ionic bonding is one method for doing this.

the answer for the ionic bond dot diagram for the Nacl was found to be.

           ··                              ··

Na· + ·Cl : ---------> Na + (: cl : )-

           ..                              ..

To learn more about ionic bond follow the given link: https://brainly.com/question/13526463

#SPJ1

Copper sulphate (CuSO4) has a molar mass of 159.6 g/mol.

What uses does copper have?

Due to its ductility and excellent conductivity, copper is mostly used in electrical generators, home and auto wiring, as well as the wires in electronics like radios, TVs, computers, lighting, and motors.

A metal or a nonmetal, is copper?

Just on Periodic Table of Elements, copper is the 29th element. It is regarded as a moderately, nonferrous, malleable metals with countless uses in the fields of electrical and electronics, plumbing, construction projects & architecture, business, transportation, & consumer and health items.

To know more aboout copper visit:

https://brainly.com/question/13677872

#SPJ1

With rising temperatures, sodium hydroxide's solubility declines when dissolved in another solvent.

Solubility refers to how easily a substance dissolves in a liquid to produce a solution (usually expressed as grams of solute per litre of solvent). One fluid's (liquid or gas) solubility in another can be complete (completely miscible; for example, methanol and water) or partial (oil and water only partly dissolve).

Solutes are divided into three categories: highly soluble, sparingly soluble, and insoluble based on the concentration at which they dissolve in a solvent.

To know more about solubility visit:

https://brainly.com/question/28170449

#SPJ1

1. Reaction of BH3 in basic condition with alkyne is the water addition to the triple bond and forming unstable enol form which in turn tautomerize to the ketone or aldehyde for terminal triple bond. Addition of water to the triple bond follows anti-Mark's rule.

In our reaction, 4-octyne under go water addition and forms a single product, 4-octanone (P1) because it is a symmetrical alkyne. Refer the below image for reaction. 2.  Reaction of H2 in Lindlar catalyst with alkyne is the H addition to the triple bond. The only product is Z alkene. In our reaction, (S)-pent-3-yn-2-ol under go reduction reaction with H2 in Lindlar catalyst and forms the Z - isomer (P2), (S,Z)-pent-3-en-2-ol. Refer the below image for reaction.

Learn more about alkenes here:

https://brainly.com/question/3614247

#SPJ4

A soil can hold more water if its surface area is larger. To put it another way, a fine soil, which is defined as soil with only a high proportion of clay and sediment particles, has a better capacity to hold water.

The material that covers the surface of the ground, known as soil, is created as a result of the weathering of rock. Its principal constituents include mineral atoms, organic substances, air, water, and living things, all of which interplay slowly yet continuously.

Although a lot of us could confuse the terms dirt and soil, they are distinct from one another thing. When it comes to nutrients or bacteria, dirt is frequently composed of clay, sands, silt, and pebbles.

To know more about Soil visit:

https://brainly.com/question/23813511

#SPJ4

The limiting reactant in the question that we have here is magnesium since it has lower yeild. Option D

If we are looking at the reactant, we are going to be looking at the reactant that is in the system that is going to lead us to obtain about the lowest amount of the products that is in the system.

Now we have in the case of the question that we have been asked that the kind of the reactant that would give the lowest amount of the product from the information in the question is magnesium.

Learn more about limiting reactant:https://brainly.com/question/14225536

#SPJ1

Lewis structure for CH₅N has one lone pair.

A lone pair, also known as an unshared pair or a non-bonding pair, is an unshared pair of valence electrons that are not shared with another atom in a covalent bond in chemistry. Atoms' outermost electron shell contains lone pairs. The Lewis structure can be used to locate them. Therefore, if two electron pairs are coupled but are not utilized in chemical bonding, they are referred to as lone pairs. As a result, the amount of valence electrons surrounding an atom is equal to the sum of the electrons in lone pairs and those in bonds.

In the valence shell electron pair repulsion theory (VSEPR theory), which describes the morphologies of molecules, the idea of a lone pair is employed. They are also mentioned in relation to Lewis acids and bases in chemistry. Chemists do not, however, always classify non-bonding electron pairs as lone pairs. Examples include transition metals, where non-bonding pairs are believed to be stereochemically inactive and do not affect molecular shape. The idea of a lone pair is less clear in molecular orbital theory (completely delocalized canonical orbitals or localized in some way), as the relationship between an orbital and the elements of a Lewis structure is sometimes not clear-cut. However, orbitals that are largely nonbonding or that are occupied are typically classified as lone pairs.

We can learn more about lewis structure here:

https://brainly.com/question/20300458#

#SPJ4

The student's error is that she is assuming that the number of atoms in a sample is directly proportional to the mass of the sample. Avogadro's number (6.022 x 10²³) represents the number of atoms or molecules in one mole of a substance. However, the number of atoms in a given mass of a substance depends on the molar mass (mass per mole) of the substance, not the Avogadro's number.

The correct way to determine the number of atoms in a sample is to use the formula:

number of atoms = mass of the sample / molar mass

In this case, the molar mass of the substance is 30 g/mol, so the number of atoms in 150 g of the substance is:

number of atoms = 150 g / 30 g/mol = 5 mol

The correct answer is 5 moles of atoms, which is not equal to 5 times Avogadro's number. Therefore, the student's answer is incorrect.The student's error is that she is assuming that the number of atoms in a sample is directly proportional to the mass of the sample. Avogadro's number (6.022 x 10²³) represents the number of atoms or molecules in one mole of a substance. However, the number of atoms in a given mass of a substance depends on the molar mass (mass per mole) of the substance, not the Avogadro's number.

The correct way to determine the number of atoms in a sample is to use the formula:

number of atoms = mass of the sample / molar mass

In this case, the molar mass of the substance is 30 g/mol, so the number of atoms in 150 g of the substance is:

number of atoms = 150 g / 30 g/mol = 5 mol

The correct answer is 5 moles of atoms, which is not equal to 5 times Avogadro's number. Therefore, the student's answer is incorrect.

The angle would need to be 180 degrees for the anti-conformation. Additional staggered conformation, known as the anti conformation, is created by adding another 60 rotations. In this structure, the two methyl groups are placed in opposition to one another.

Dihedral, which is the upward angle of an aircraft's wings, makes the lower wing fly at a higher angle of attack than the higher wing, increasing lateral stability in a bank. In reality, it just means that you can fly more autonomously, especially during turbulence.

The angle between an aircraft's left and right wings is known as dihedral in aeronautics. The impact of sideslip on the aircraft's rolling is also referred to as "dihedral."

To know more about Dihedral visit:

https://brainly.com/question/21684710

#SPJ4