how many electrons does phosphorus need to gain to have a stable outer electron shell
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Answer:

A.) -5448 kJ/mol

Explanation:

I got it correct on founders edtell

Answer:

The percentage yields are as follows :

a) 64.28%

b) 58.03%

c) 69.46%

d) 79.31%

Explanation:

The percentage yield is the ratio of the actual yield of a product to the expected or theoretical yield expressed as a percentage.

Percent yield = actual yield/theoretical yield x 100%

a) from the question, expected yield is 68.3 g whilst the actual yield is 43.9 g

therefore,

Percentage yield = 43.9 g/68.3 g x 100%

                             =  0.64275 x 100%

                             =  64.28%

b) From the question, expected yield is 0.0722 mol while the actual yield is 0.0419 mol. Therefore

Percentage yield = 0.0419 /0.0722 x 100%

                             = 0.58033 x 100%

                             = 58.03%

c) A limiting reactant is the reactant is is completely used in a recation to form a product. That is, it is the reactant that is not in excess.

From the equation of the reaction :

CH3COOH + CH3CH2OH --> CH3COOCH2CH3 + H2O

1 mole of ethanol reacts with 1 mole of acetic acid to give 1 mole of ethyl acetate.

From the question, ethanol is the limiting reactant because it is not in excess. Hence,

4.29 mole of ethanol should produce 4.29 mole of ethyl acetate (expected yield).

However only 2.98 mol of ethyl acetate is produced (actual yield)

Percentage yield = 2.98mol/4.29 mol x 100%

                            =  0.69463 x 100%

                            = 69.46%

d) From the question, acetic acid is in excess hence ethanol is the limiting reactant

therefore from the equation of the reaction:

1 mole of ethanol reacts with 1 mole of acetic acid to give 1 mole of ethyl acetate.

0,58 mol of ethanol should produce 0.58 mol of ethyl acetate (expected yield)

But 0.46 mol of ethyl acetae was produced (actual yield)

Percentage yield = 0.46mol /0.58 mol x 100%

                             = 0.79310 x 100%

                              = 79.31%

Answer:

NO most of the time

Explanation:

I hope this is for school and not personal reasons. Bleach will kill you if drank plain, if it's diluted a little it may not be fatal but can still greatly harm your organs. If it is diluted extremely it is used for cleaning tap water and is perfectly fine.

Just to be on the safe side, I want you to know there is always help, and if you need someone to talk or text this is the number for the National Su1c1de Hotline and it is free and available if you are ever feeling like self harm is the only way out:

800 273 8255

Answer:

A group of cells working together is defined as a tissue and several tissues working together comprise an organ.

Explanation:

Answer:

The answer is A. Unlike other maps, topographic maps indicate man-made and natural landforms.

Explanation: Took the test and got 100% Edg. 2020

Answer:

A)Unlike other maps, topographic maps indicate man-made and natural landforms.

Explanation:

Answer:

C7H16 + 11O2 = 7CO2 + 8H2O

Explanation:

Start by balancing the C and H in C7H16 by adding the coefficient of 7 for CO2 because there are 7 C's in C7H16. Similarly, since there are 16 H's in C7H16, balance it by adding the coefficient of 8 to the H2O, which will result in 16 H's.

Finally, add up the O's on the right side and balance it by adding the appropriate coefficient on the O2. On the right, there are 22 O's, so balance the equation by adding the coefficient of 11 on the left for the O2.

Answer:

The empirical formula is same as the molecular formula = C6H10S2O

Explanation:

we start by dividing the percentage of each of the elements by their atomic mass

Carbon = 44.4/12 = 3.7

Hydrogen = 6.21/1 = 6.21

Sulphur = 39.5/32 = 1.234375

oxygen = 9.89/16 = 0.618125

That of oxygen is smallest so we divide all by that of oxygen

C = 3.7 / 0.618125 = 6

H = 6.21/ 0.618125 = 10

S = 1.234375/ 0.618125 = 2

Automatically, oxygen is 1

So the empirical formula is;

C6H10S2O

Let’s get its molecular formula. We multiply each of the subscript by the number;

(72 + 10 + 64 + 16)n= 162

162n = 162

n = 1

So the molecular formula is same as the empirical formula

Answer:

THE NORMAL BOILING POINT OF A SOLUTION CONTAINING 64.5 g OF QUINOLINE IN 500 g OF BENZENE IS 82.6 C

Explanation:

Boiling point = old boiling point + molarity * boiling point constant (Kb)

First, you calculate the number of moles of quinoline in the solution

number of moles = mass / molar mass

Since the molar mass of quinoline has been given as 129 g/mol

number of moles = 64.5 g / 129 g/mol

number of moles = 0.5 moles.

Next is to determine the molarity:

molarity = number of moles of solute / kilogram of solvent

molarity = 0.5 moles / 500/1000 kg

molarity = 0.5 / 0.5

molarity = 1 M

The new boiling point can then be calculated using the formula:

B. P = old B.P + Kb * molarity

B.P = 80.10 + 2.50 * 1

B.P = 80.10 + 2.50

B.P = 82.6 degree celsius

Answer:

Titanium; lowest density  

Explanation:

The cart would use the same volume of metal, no matter which one it was made of.

If weight were the only consideration, the company would choose the metal with the lowest density.

The values I find for the metals are

Ti   4.5 g/cm³

Fe  7.9 g/cm³

Zn  7.1  g/cm³

Titanium would be the best metal for this application.

Answer:

Titanium would be the best metal for this application because it is a low density metal that is still strong  and ductile

Explanation:

Answer:

Four main processes erode the destructive waves; hydraulic action, compression, abrasion and attrition. Hydraulic Action is the sheer force of water crashing off the coastline causing the material to dislodge and be carried away by the sea.

Answer:

a

Explanation:

Answer:

whole continents can move.

Answer:

No oxygen

Explanation:

when something is covered in a blanket it prevents the fire from being able to have any oxygen

Answer:

Its called smothering the fire

Explanation:

A fire needs three things to burn always: fuel, oxygen, and a heat source. Eventually the heat source will not be an issue, but the oxygen and fuel is. If the fire is small enough throwing a blanket can quite smother it. What happens is it cuts off the oxygen supply the fire needs long enough for it to die out.

Options are not given in the question. The complete question is as follows:

Read the following statements carefully: X: It is a thick black coloured liquid which is obtained from coal.Y: It was used earlier in railway engines to produce steam to run trains.Z : It is used to run heavy vehicles such as buses, trucks, tractors, etc.X, Y and Z respectively are

A. a. Coal tar b. Coal c. Diesel

B. a. Coal b. Paraffin wax c. Petrol

C. a. Coke b. Coal tar c. Kerosene

D. a. Coke b. Coal c. Coal tar

Answer:

A. a. Coal tar b. Coal c. Diesel

Explanation:

Coal Tar is a thick black or dark brown colored liquid obtained from coal. Coal Tar consists of hydrocarbons and free carbon extracted from coal using a process of destructive distillation. So, X is coal tar.

Earlier coal was used to produce steam to run steam engine trains. Air flows are allowed to burn coal hotter, then the hot coal turns water to steam and helps in the locomotive steam engine to run. So, Y is coal.

Deisel is used to run heavy vehicles such as buses, trucks, tractors, etc. because diesel burns at slow speed and produces a higher torque that can move heavy automobiles. So, Z is deisel.

Hence, the correct option is A.

Answer:

Normal boiling point is the temperature at which a liquid boils at 1 atmosphere of pressure.

Explanation:

Answer: because the phospholipid bilayer formed by these interactions makes a good barrier between the interior and exterior of the cell, because water and other polar or charged substances cannot easily cross the hydrophobic core of the membrane.

Explanation:

Energy change is the conversion of the energy stored in reactants to products. In the reaction between hydrogen and iodine, the energy change is -7 kJ/mol. Thus, option D is correct.

Total energy change is the conversion of the energy from a substance to another when the reactant undergoes modification to produce a product.

The reaction is given as,

H₂ + I₂ → 2HI

In the reaction, the bonds between H-H and I-I are broken to release energy that produces two H-I bonds as the product.

Given,

H-H bond = 436 kJ/mol

I-I bond = 151 kJ/mol

H-I bond = 297 kJ/mol

So, 436 kJ/mol + 151 kJ/mol - 2x297 kJ/mol = -7 kJ/mol

Therefore, -7 kJ/mol is the total energy change in the reaction involving hydrogen and iodine.

Learn more about total energy change here:

https://brainly.com/question/14769257

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Answer:

gold

Explanation:

Answer:

It continuously decreases.

Explanation:

the thermal motion makes the electrons to collide and disturb the free flow. Thus, conductivity is decreased.

Answer: Quartz

Explanation: I looked it up ;)

Answer:

False

Explanation:

Catalysts are reusable because they keep the chemical reactions moving without being consumed.

Answer:

Final volume of the gas is 4.837mL

Explanation:

Initial volume (V1) = 350mL = 0.35L

Initial temperature (T1) = 0°C = (0 + 273.15)k = 273.15k

Initial pressure (P1) = 1.0atm

Final volume (V2) = ?

Final temperature (T2) = 10°C = (10 + 273.15)k = 283.15K

Final pressure (P2) = 75atm

To solve this question, we'll have to use combined gas equation which is the combination of all gas law I.e Charle's laws, Boyle's law, Pressure law etc.

According to combined gas equation,

(P1 × V1) / T1 = (P2 × V2) / T2

Make V2 the subject of formula,

V2 = (P1 × V1 × T2) / (P2 × T1)

V2 = (1.0 × 0.35 × 283.15) / (75 × 273.15)

V2 = 99.1025 / 20,486.25

V2 = 0.004837L

V2 = 4.837mL

The final volume of the gas is 4.837mL

Answer:

4.84mL

Explanation:

Step 1:

Data obtained from the question. This include the following:

Initial volume (V1) = 350mL

Initial temperature (T1) = 0°C

Initial pressure (P1) = 1atm

Final temperature (T2) = 10°C

Final pressure (P2) = 75atm

Final volume (V2) =...?

Step 2:

Conversion of celsius temperature to Kelvin temperature.

This can be achieved by using the formula below:

T(K) = T (°C) + 273

Initial temperature (T1) = 0°C

Initial temperature (T1) = 0°C + 273 = 273K

Final temperature (T2) = 10°C

Final temperature (T2) = 10°C + 273 = 283K

Step 3:

Determination of the new volume.

The new volume can be obtained by using the general gas equation as follow:

P1V1/T1 = P2V2/T2

1 x 350/273 = 75 x V2/283

Cross multiply

273 x 75 x V2 = 1 x 350 x 283

Divide both side by 273 x 75

V2 = (1 x 350 x 283) / (273 x 75)

V2 = 4.84mL

Therefore, the new volume is 4.84mL

Explanation:

They allow the bonds between oxygen and hydrogen to be single. They increase the partial positive charge on the oxygen atom. They counter the uneven pull on electrons between the atoms.

Answer: [tex]PCl_5[/tex] is not an ionic compound.

Explanation:

An ionic compound is defined as the compound which is formed when electron gets transferred from one atom to another atom.  The cation is formed by loss of electrons by metals and anions are formed by gain of electrons by non metals.

Thus [tex]MoCl_6[/tex], [tex]RbCl[/tex], [tex]PbCl_2[/tex] and [tex]NaCl[/tex] are all ionic compounds.

Covalent compound is defined as the compound which is formed by the sharing of electrons between the atoms forming a compound. These are usually formed when two non-metals react.

Thus [tex]PCl_5[/tex] is a covalent compound as both Phosphorous and chlorine are non metals.

PCl₅ is not an ionic compound. Ionic or electrovalent compounds are formed

through the transfer of electrons in a chemical reaction. Metals and non-

metals mostly form ionic compounds.

Covalent bonding on the other involves the sharing of electrons between

two elements. Non-metals are mostly involved in this type of reaction.

PCl₅ possesses a covalent bond and not ionic as electrons are shared

between two non metals  which are phosphorus and chlorine.

Read more on https://brainly.com/question/957239

Answer: The reaction will shift in left or backward direction.

Explanation:

Any change in the equilibrium is studied on the basis of Le-Chatelier's principle. This principle states that if there is any change in the variables of the reaction, the equilibrium will shift in the direction to minimize the effect.

For the given equation:

[tex]H_2(g)+I_2(g)\rightleftharpoons 2HI(g)+heat[/tex]

As the given reaction is exothermic as the heat is released in the reaction. When the temperature is raised , the reaction will shift in a direction where temperature is decreasing and that is the reverse reaction which is endothermic in nature.

Thus the reaction will shift in left or backward direction.

Answer:

changes from a solid to a liquid

Explanation:

C- A solid is being formed

Since the delta is negative, this indicates that a substance is transforming from a liquid state to a solid state. This best corresponds with C- A solid is being formed.

Answer:

B= 17649.28/A

Explanation:

Answer:

ExpPolyploidy is the heritable condition of possessing more than two complete sets of chromosomes. Polyploids are common among plants, as well as among certain groups of fish and amphibians. For instance, some salamanders, frogs, and leeches are polyploids. Many of these polyploid organisms are fit and well-adapted to their environments. In fact, recent findings in genome research indicate that many species that are currently diploid, including humans, were derived from polyploid ancestors (Van de Peer & Meyer, 2005). These species that have experienced ancient genome duplications and then genome reduction are referred to as paleopolyploids. This article discusses the mechanisms underlying polyploidy, and both the advantages and disadvantages of having multiple sets of chromosomes.

Mechanisms of Polyploidy

This diagram shows several pathways by which diploid species can transition to polyploid species and polyploid species can transition to diploid species. Each species is represented by an oval containing two or more colored circles. Each colored circle represents a complete set of chromosomes.

View Full-Size ImageFigure 1

Figure Detail

How does an organism become polyploid? Polyploids arise when a rare mitotic or meiotic catastrophe, such as nondisjunction, causes the formation of gametes that have a complete set of duplicate chromosomes. Diploid gametes are frequently formed in this way. When a diploid gamete fuses with a haploid gamete, a triploid zygote forms, although these triploids are generally unstable and can often be sterile. If a diploid gamete fuses with another diploid gamete, however, this gives rise to a tetraploid zygote, which is potentially stable. Many types of polyploids are found in nature, including tetraploids (four sets of chromosomes), hexaploids (six sets of chromosomes), and other chromosome-pair multiples

Answer:

he thought of atoms first

Answer:

He was the first to be the one to propose that matter is made out of atoms. He also proved that the atoms are divisible in nature.