To all Moderators and Trusted Answerers or Grandmaster answerers please help me!!!

Copied Answer will be reported!​

Answer:

this problem was eventually overcome by arranging elements by increasing atomic number instead of atomic weight.

This problem was eventually overcome by arranging elements by increasing atomic number instead of atomic weight.

The total weight of an atom is called the atomic weight. It is approximately equal to the number of protons and neutrons, with a little extra added by the electrons.

Mendeleev arranged the elements in order of increasing weight and broke them into rows such that elements in each column shared valence, the number of other atoms they combined with, as well as other properties.

In his 1869 Periodic Table, Mendeleev left blanks with suggested atomic weights for elements he thought would be discovered someday. William Ramsay's discovery of argon initially posed a threat to the Periodic Table. At first, Mendeleev believed argon was not an element, because it didn't react with anything.

Hence, this problem was eventually overcome by arranging elements by increasing atomic number instead of atomic weight.

Learn more about the atomic weight here:

https://brainly.com/question/13000210

#SPJ2

The best reactant is: iPrCl

The best reagent is: Mg

The best solvent is: CH3CH2OCH2CH3

A chemical molecule with the general formula RMgX, where X is a halogen and R is typically an alkyl or aryl group, is known as a Grignard reagent or Grignard compound. Methylmagnesium chloride (ClMgCH3) and phenylmagnesium bromide (C6H5)-Mg-Br, respectively, are two prominent examples. They fall within the category of organomagnesium compounds.

Typically, magnesium ribbon is needed for the reaction that results in the synthesis of Grignard reagents. A magnesium oxide passivating coating protects the whole magnesium, preventing interactions with organic halides. As an initiator, Grignard's prepared reagent can also be applied.

Learn more about Grignard reagent here:-

https://brainly.com/question/15871695

#SPJ4

The number of mole of ethanol present in the sample is 0.005 mole

The mole of a substance is related to it's mass and molar mass according to the following equation

Mole = mass / molar mass

With the above formula, we can obtain the mole of ethanol

Mole = mass / molar mass

Mole of ethanol = 0.2301 / 46

Mole of ethanol = 0.005 mole

Complete question

A sample of ethanol (C2H6O) has a mass of 0.2301 g. Complete combustion of this sample causes the temperature of a bomb calorimeter to increase by 1.33°C. The calorimeter has a mass of 2.000 kg and a specific heat of 2.45 J/g•°C. How many moles of ethanol are present in the sample?

Learn more about mole:

https://brainly.com/question/13314627

#SPJ1

Answer:

-Unknown

Explanation:

Questions is not seen properly bro

Taking into account the Charles' law, the temperature of the gas if the volume drops to 75.0 L is 246 K or -27 C.

Charles' law establishes the relationship between the temperature and the volume of a gas when the pressure is constant. This law says that for a given sum of gas at constant pressure, as the temperature increases, the volume of the gas increases and as the temperature decreases, the volume of the gas decreases. That is, the volume is directly proportional to the temperature of the gas.

Mathematically, Charles' law is a law that says that when the amount of gas and pressure remain constant, the ratio between volume and temperature will always have the same value:

[tex]\frac{V}{T}=k[/tex]

Considering an initial state 1 and a final state 2, it is fulfilled:

[tex]\frac{V1}{T1}=\frac{V2}{T2}[/tex]

In this case, you know:

Replacing in Charles's law:

[tex]\frac{100 L}{328 K}=\frac{75 L}{T2}[/tex]

Solving:

[tex]T2x\frac{100 L}{328 K}=75 L[/tex]

[tex]T2=\frac{75 L}{\frac{100 L}{328 K}}[/tex]

T2= 246 K= -27 C

Finally, the temperature of the gas if the volume drops to 75.0 L is 246 K or -27 C.

Learn more about Charles' law:

https://brainly.com/question/4147359

#SPJ1

The total mass of the protons is 1.338 * 10^-23 g

A proton is the positively charged particle in an atom. It is found in the nucleus along with the neutrons and are collectively called the nucleons.

The hydrogen atom has only one proton while the nitrogen atom has seven protons. Thus makes a total of eight protons in the ammonia molecule.

Hence, the total mass of protons in the ammonia molecule =

8 ( 1.673 × 10^-24 g) = 1.338 * 10^-23 g

Learn more about protons:https://brainly.com/question/1252435

#SPJ1

Answer:

C. None of these

2 volumes of zinc sulphide produces two volumes of Sulphur dioxide. So, 9.7g of ZnS will produce nothing less than 9.7g of SO2.

The dehydration-condensation reaction occurs between 'ethanol' and 'butanoic acid' giving an ester called as "ethyl butanoate".

Esters are produced when carboxylic acids are heated with alcohols in the presence of an acid catalyst.

The catalyst is usually concentrated sulphuric acid.

Dry hydrogen chloride gas is used in some cases, but these tend to involve aromatic esters (ones containing a benzene ring).

Esters are represented by the formula RCOOR', where R and R' are hydrocarbon groups.

The chemical reaction occurring in the formation of the ester is known as an esterification reaction.

The reaction that occurs between ethanol and butanoic acid:

Ethanol reacts with butanoic acid in the presence of an acid-catalyst and gives ethyl butanoate as ester and water as products. If an acid reacts with a base, salt and water are the products. But ester is not a salt.

i) The carbon skeletal notation for the given reaction is shown below.

ii) The ester is named "ethyl butanoate".

Learn more about esterification here:

brainly.com/question/14028062

#SPJ1

Explanation:

sulphur has a low melting point.

sulphur has a low boiling point thus it can be extracted by pumping hot water which turns it ito solution form

[tex]V^{2+}[/tex]is the symbol of the species with 23 protons and 21 electrons.

Hence, option F is correct.

Electrons are a type of subatomic particle with a negative charge. Protons are a type of subatomic particle with a positive charge.

If it has 23 protons, then its proton number (also know as its atomic number) is 23. You can look that symbol up in your periodic table.

If it has 21 electrons then it has a net charge of 23(+) - 21. So we know the ionisation state of the species, and we can record that as a superscript after the symbol for the species.

Hence, [tex]V^{2+}[/tex] is the symbol of the species with 23 protons and 21 electrons.

Learn more about the proton here:

https://brainly.com/question/1252435

#SPJ1

In a Base catalyst elimination, the base extracts a proton and the leaving group leaves simultaneously. In a Concentrated process, the leaving group leaves  the base abstracts a proton.

Just as there are two mechanisms of substitution (SN2 and S N1), there are two

mechanisms of elimination (E2 and E1).

E2 mechanism — bimolecular elimination

E1 mechanism — unimolecular elimination

The E2 and E1 mechanisms differ in the timing of bond cleavage and bond formation, analogous to the SN2 and S N1 mechanisms.

E2 and S N2 reactions have some features in common, as do E1 and SN1 reactions.

Base removes a proton from the β-carbon atom,

while the halogen atom leaves from the α-carbon resulting in the formation of a π-bond. Such eliminations are also called β-eliminatione liminations are also called β elimination reactions

In a base-catalyzed elimination reaction, the base takes away a proton from the β position of the leaving group (the group that goes away with the bonding pair of electrons) and a double bond is formed. When the base is bulky it prefers to take away the proton from the less hindered position.

Learn more about base catalyst here:

https://brainly.com/question/12507566

#SPJ4

19.7 litre volume of carbon dioxide gas at 22.0o C and 102 kPa can be collected over water.

Vapour pressure is a measure of the tendency of a material to change into the gaseous or vapour state, and it increases with temperature.

Moles of Butane = mass in grams / molar mass = 11.6 / 58.12 = 0.2

Volume of [tex]O_2[/tex] (V) = 40 liter

Temperature (T) = 22°C = 22 + 273 = 295 K

Pressure (P) = 102 kPa = 102 / 101.325 = 1.007 atm

Moles of [tex]O_2[/tex] (n) can be calculated by ideal gas equation.

PV = nRT

n = 1.007 40 ÷ 0.0821 295 = 1.663

Balanced chemical reaction;

2[tex]C_4H_10[/tex] + 13[tex]O_2[/tex] ---> 8[tex]CO_2[/tex] + 10[tex]H_2O[/tex]

From reaction;

13 moles [tex]O_2[/tex] require 2 moles [tex]C_4H_10[/tex]

So, 1.663 moles [tex]O_2[/tex] will require = 2 x 1.663 ÷13 = 0.256 moles of [tex]C_4H_10[/tex]

Thus [tex]C_4H_10[/tex] is a limiting reagent. So it will drive the yield of [tex]CO_2[/tex].

Moles of [tex]CO_2[/tex] produced = (8/2) 0.2 = 0.8 moles

Pressure of [tex]CO_2[/tex] (P) = 102 - 2.24 = 99.76 kPa = 99.76  ÷ 101.325 = 0.985 atm

Applying the ideal gas equation for [tex]CO_2[/tex],

PV = nRT

0.985 V = 0.8 0.0821 x 295

V = 19.7 liter

The volume of [tex]CO_2[/tex] produced = 19.7 liter.

Learn more about the vapour pressure here:

https://brainly.com/question/25699778

#SPJ1

The molarity of KOH is 0.2678 moles/L.

           Molarity(M) = number of moles/ volume of solutions in liter.

      Number of moles(n) = mass of the substance/Molar mass

The mass of Oxalic acid is 0.546g.

The molar mass of Oxalic acid [tex]H_{2}C_{2}O_{4}[/tex] is 90g (1*2+12*2+16*4=90)

The number of moles of Oxalic acid is,

n = 0.546/90

n = 0.006 moles

So, the number of moles of Oxalic acid is 0.006 moles.

The volume of KOH is 22.40mL = 22.40*1000 = 0.0224L

Therefore the molarity of KOH is,

M = number of moles/ volume of solutions in liter

M = 0.006/0.0224

M = 0.2678 moles/L

Therefore, the molarity of KOH is 0.2678 moles/L

Learn more about molarity at https://brainly.com/question/14469428

#SPJ4

Answer:

Option B

Explanation:

Therefore our answer must be Option B

Answer: C. 1.40×10^24

Explanation:

To do this, we must convert this from grams to moles, then from moles to molecules. For the first step, you will need to find the molar mass of HCl on the periodic table, which is 36.461gHCl.

[tex]85.0gHCl*\frac{1molHCl}{36.461gHCl} =2.33molHCl[/tex]

Now that we have the moles, we must convert that to molecules by using Avogadro's number.

[tex]2.33molHCl*\frac{6.022*10^{24} }{1molHCl} =1.40*10^{24}[/tex]

Now we have our answer. The best answer choice here is C. 1.40×10²⁴.

I hope this helps! Pls mark brainliest!! :)

B

A mixture can be separated by a physical means because there is no chemical bond between the constituents

Answer:

6 (STI, SIT, TIS, ITS, IST

The volume of the piece of iron to the nearest cubic centimeter is 4473.6 cubic centimeter.

density = mass / volume

volume = mass/ density

            =35342/ 7.9

            =4473.6 cubic centimeter

The density of a substance indicates how dense it is in a given area. Mass per unit volume is the definition of a material's density. In essence, density is a measurement of how closely stuff is packed. It is a particular physical characteristic of a specific thing. The Greek scientist Archimedes made the discovery of the density principle. If you are familiar with the formula and the relevant units, calculating density is simple. The letter D can also be used to signify density instead of the symbol.

Learn more about Density here:-

https://brainly.com/question/6838128

#SPJ4

The red colour is the limiting reactant.

Red-blue colour ball and two white balls attached together are reactants.

Red-blue colour ball and two white and one red colour ball attached to each other are products.

The reactant that is entirely used up in a reaction is called a limiting reagent.

A reactant is a substance that is present at the start of a chemical reaction. The substance(s) to the right of the arrow are called products.

A product is a substance that is present at the end of a chemical reaction.

Hence,

The red colour is the limiting reactant.

Red-blue colour ball and two white balls attached together are reactants.

Red-blue colour ball and two white and one red colour ball attached to each other are products.

Learn more about limiting reagents here:

brainly.com/question/26905271

#SPJ1

Three examples of environmental, industrial and bio-chemistry are listed below:

Chemistry can be defined as a branch of science which is concerned with the substances matter is composed of, their properties and reactions,

Chemistry also deals with the use of such reactions to form new substances.

In conclusion, Three examples of environmental, industrial and bio-chemistry are listed anove

Learn more about chemistry: https://brainly.com/question/24419453

#SPJ1

Answer:

37

Explanation:

( 98.6 - 32 ) × 5(100c) ÷ 9(180f) = 37

A key element to a successful response to a chemical, biological, or radiological incident is the rapid identification of the hazard and immediate control over all responding units.

Rapid techniques commonly used for species identification consist of species-precise primer pairs and probes, randomly amplified polymorphic DNA (RAPD), amplified fragment period polymorphisms (AFLP), restriction fragment length polymorphisms (RFLP), and karyotyping.

Elements favoring fast identity kits are reduced time in getting ready, inoculating, incubating, and cleaning up; also a convenience, decreased area for trying out and garage, ease of operation, and saving of cloth and cash are many motives for the food industry to use rapid identification structures for ordinary.

A urine lifestyle test can discover micro organism or yeast causing urinary tract contamination (UTI). If microorganisms multiply, an antibiotic sensitivity take look at can discover the antibiotic most in all likelihood to kill those specific bacteria. Your healthcare issuer may additionally order a urine tradition if you get persistent or difficult-to-deal with UTIs.

Learn more about rapid identification here https://brainly.com/question/14032010

#SPJ4

Molar mass

No of moles

Volume

Explanation:

show the volume of container is equal to 198.82ml

Answer: 2.11 g

Explanation:

[tex]$$Equation: $2 \mathrm{AgC}_{2} \mathrm{H}_{3} \mathrm{O}_{2}(a q)+\mathrm{Cu}(s) \longrightarrow \mathrm{Cu}\left(\mathrm{C}_{2} \mathrm{H}_{3} \mathrm{O}_{2}\right)_{2}(a q)+2 \mathrm{Ag}(s)$[/tex]

[tex]$$No of moles of $\mathrm{Ag}$ produced from $\mathrm{Cu}=2.500 \mathrm{~g} \times \frac{1 \mathrm{~mol} \mathrm{Cu}}{63.55 \mathrm{~g}} \times \frac{2 \mathrm{~mol} \mathrm{Ag}}{1 \mathrm{~mol} \mathrm{Cu}}$ $=0.07868 \mathrm{~mol} \mathrm{Ag}$[/tex]

[tex]$$No of moles of $\mathrm{Ag}$ produced from $\mathrm{AgC}_{2} \mathrm{H}_{3} \mathrm{O}_{2}=200.0 \mathrm{~mL} \times \frac{1 \mathrm{~L}}{1000 \mathrm{~mL}} \times \frac{0.150 \mathrm{~mol} \mathrm{AgC_{2 } \mathrm { H } _ { 3 } \mathrm { O } _ { 2 }}}{1 \mathrm{~L}}$ $=0.0300 \mathrm{~mol} \mathrm{Ag}$[/tex]

[tex]Since $\mathrm{AgC}_{2} \mathrm{H}_{3} \mathrm{O}_{2}$ limits the production of $\mathrm{Ag}, \mathrm{AgC}_{2} \mathrm{H}_{3} \mathrm{O}_{2}$ acts as the limiting reactant \\\\No of moles of Ag formed $=0.0300 \mathrm{~mol}$\\Theoretical yield of $\mathrm{Ag}=0.0300 \mathrm{~mol} \mathrm{Ag} \times \frac{108 \mathrm{~g}}{1 \mathrm{~mol} \mathrm{Ag}}=3.24 \mathrm{~g}$\\Actual yield of silver $=65.0 \%(3.24 \mathrm{~g})$$$=\frac{65.0}{100}(3.24 \mathrm{~g})=2.106 \mathrm{~g} \approx 2.11 \mathrm{~g}$$[/tex]

Answer:

1s22s22p6: Neon (Ne)

1s22s22p63s23p3: Phosphorous (P)

1s22s22p63s23p64s1: Potassium (K)

1s22s22p63s23p64s2(im not sure what 308 is supposed to be): Calcium (Ca)

1s22s22p63s23p64s23d104p65s24d3: there is no pure element that ends 4d3 that I know of so this can either be Zirconium(Zr) if it ends in 4d2 or Niobium (Nb) if it ends in 4d4

Explanation:

you can look at the periodic table and the trends to find the rough idea of where the electron configuration ends, there are helpful articles and images on these, i attached an image that may help. After that you can look at the atomic number to find the number of electrons for a pure element and use the electron subshell pattern thing to find the exact number

The Faradays transferred during the process is 86400 C.

An electric current in a circuit is calculated by dividing the total charge that runs in the circuit with the total time taken.

I = Q/t

Rearrange the formula to express it in terms of charge.

Q = I x t

Calculations:

Convert 12 h to s.

12 h = (12 x 60 x 60) s = 43200 s

Substitute the values in the above formula.

Q = 2.0 C/s x 43200 s

= 86400 C

Therefore, the charge (Faradays) transferred in an electrolytic cell is 86400 C.

Learn more about electrolytic cell here:

https://brainly.com/question/4030224

#SPJ4

The given question is based on the concept of conversion factor

1 KL = 10³ L, 1cL = 10⁻³ L, 1dL = 10⁻² L, 1 nL = 10⁻⁹ L

A conversion factor is an expression for the relationship between units that is used to change the units of a measured quantity without changing the value.

A conversion ratio (or unit factor) always equals one (1), where the numerator and the denominator have the same value expressed in different units.

Hence, The complete filled table is given as follows ;

1 KL = 10³ L,

1cL = 10⁻³ L,

1dL = 10⁻² L,

1 nL = 10⁻⁹ L

Where,

Learn more about conversion factor here ;

https://brainly.com/question/1844638

#SPJ1