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Answer:

neon

Explanation:

The octet rule states that atoms of elements are stable when they possess 8 electrons on their outermost shell.

Hence, atoms of elements participate in chemical reactions in order to attain this octet structure (eight electrons in the outermost shell).

Neon is a noble gas and already has eight electrons in its outermost shell. Hence, neon is least likely to obey the octet rule.

Answer:

2 Cu + O2 → 2 CuO

This is an oxidation-reduction (redox) reaction:

2 Cu0 - 4 e- → 2 CuII

(oxidation)

2 O0 + 4 e- → 2 O-II

(reduction)

Cu is a reducing agent, O2 is an oxidizing agent.

Answer:

That is a " ball and stick " model which represents carbon compounds.

Explanation:

This is the answer. Hope it helps you find what you're looking for.

Answer:

option a

hope helps you

have a great day

Answer:

yes

Explanation:

it is important for electrolysis

Answer:

0.9433g

Explanation:

Theoretical yield is defined as the mass produced assuming all reactant reacts producing the product.

Assuming the reaction is 1:1, we need to find the moles of E-stilbene (Reactant). If all reactant reacts, the moles of E-stilbene = Moles of product.

Using the molar mass of the product we can find the theoretical yield as follows:

Moles E-stilbene:

0.50g * (1mol/180.25g) = 0.00277 moles = Moles Product

Mass Product = Theoretical yield:

0.00277 moles * (340.058g/mol) = 0.9433g

Answer:

104.8 g

Explanation:

From the question given above, the following data were obtained:

Initial temperature of copper (T꜀) = 275.1 °C

Mass of water (Mᵥᵥ) = 272 g

Initial temperature of water (Tᵥᵥ) = 21 °C

Equilibrium temperature (Tₑ) = 29.7 °C

Mass of copper (M꜀) =?

NOTE:

Specific heat capacity of copper (C꜀) = 0.385 J/gºC

Specific heat capacity of water (Cᵥᵥ) = 4.184 J/gºC

Finally, we shall determine the mass of the copper in the sample. This can be obtained as follow:

Heat loss by copper = Heat gained by water

M꜀C꜀(T꜀ – Tₑ) = MᵥᵥCᵥᵥ(Tₑ – Tᵥᵥ)

M꜀ × 0.385 (275.1 – 29.7) = 272 × 4.184(29.7 – 21)

M꜀ × 0.385 × 245.4 = 1138.048 × 8.7

M꜀ × 94.479 = 9901.0176

Divide both side by 94.479

M꜀ = 9901.0176 / 94.479

M꜀ = 104.8 g

Thus, the mass of the copper in the sample is 104.8 g

Answer:

1.30 m

Explanation:

First we calculate the number of moles of solute in the solution, using the definition of molarity:

Then we calculate the mass of solvent, using the given volume and density:

Now we calculate the molality of the solution:

Answer:

Potassium carbonate (K₂CO₃)

Explanation:

The compounds dissociate into ions in water, as follows:

K₂CO₃ → 2 K⁺ + CO₃⁻    ⇒ 3 dissolved particles per mole

NaI → Na⁺ + I⁻    ⇒ 2 dissolved particles per mole

KBr → K⁺ + Br⁻   ⇒ 2 dissolved particles per mole

CH₃OH → CH₃O⁻ + H⁺  ⇒ 2 dissolved particles per mole

NH₄Cl → NH₄⁺ + Cl⁻   ⇒ 2 dissolved particles per mole

Therefore, the largest number of dissolved particles per mole of dissolved solute is produced by potassium carbonate (K₂CO₃).

Answer:

11

1. 6.02×10 23

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Answer:

Melting-point apparatus

Answer:

See explanation

Explanation:

Science as a body of knowledge seeks to understand the processes that occur in nature so as to offer plausible explanations to those processes as well as redesign nature for our benefit.

Hence, science is an inquiry into nature with the aim to improve the life of the general population of the world.

Chemistry is the study of matter and the changes that matter undergoes. Chemistry lies at the very foundation of science since changes in matter is the basis for the processes that occur in nature.

Hence, chemistry plays a critical role in understanding nature as well as amending nature to improve the living condition of the world's rapidly growing population.

Answer:

On the basis of your knowledge of the reaction of halogens with alkanes, decide which product you would not expect to be formed in even small quantities in the bromination of ethane?

A) BrCH2CH2Br

B) CH3CH2CH2Br

C) CH3CHBr2

D) CH3CH2CH2CH3

E) BrCH2CH2CH2CH2Br

Explanation:

The reaction of ethane with bromine in presence of UV light forms mono substituted ethane at all primary and secondary carbons.

This is an example of free radical substitution.

The structure of ethane and its bromination is shown below:

Among the given options that which is not possible to form is option B) that is CH3CH2CH2Br(propyl bromide).

Remaining all other products are possisble to form on free radical substitution of ethane.

Answer:

There are a variety of methods by which a sample's boiling point can be determined, including distillation, reflux, and by using a Thiele tube. The most straightforward method uses a Thiele tube, and has the advantage of using less than 0.5mL of material.

Distillation Method

There are simpler methods than a distillation to measure a compound's boiling point, and it is recommended to explore other options (e.g. Thiele tube) if this is the only goal. However, if materials are limited, or if a purification is planned anyhow, a distillation can be used to determine a compound's boiling point. The distillation technique is discussed in great detail in Chapter 5.

A simple distillation should suffice for most situations and at least 5mL of sample should be used in the distilling flask along with a few boiling stones or stir bar. As the bulk of the material distills, the highest temperature noted on the thermometer corresponds to the boiling point. A major source of error with this method is recording too low a temperature, before hot vapors fully immerse the thermometer bulb. 5 Be sure to monitor the thermometer periodically, especially when the distillation is active. Record the barometric pressure along with the boiling point.

Reflux Method

A reflux setup can also be used to determine a compound's boiling point. Reflux is when a liquid is actively boiling and condensing, with the condensed liquid returning to the original flask. It is analogous to a distillation setup, with the main difference being the vertical placement of the condenser.

Thiele Tube Method

There are a variety of methods by which a sample's boiling point can be determined, including distillation, reflux and by using a Thiele tube. The most straightforward method uses a Thilele tube, and has the advantage of using less than 0.5ml of material.

Answer:

SN1 substitution reaction

Explanation:

cyclohexanol is a secondary alkanol. The mechanism of acid catalysed dehydration of cyclohexanol involves the protonation of the -OH group.

This is followed by loss of water which is a good leaving group. At this stage, a proton could be abstracted to yield cyclohexene by E1 mechanism or an SN1 substitution reaction may occur to yield Cyclohexyl chloride.

The both reactions are equally likely.

Answer:

264 g/mol

Explanation:

#electrons equal #protons = 106

Plus 1 charge => m protons = 106 + 1 = 107

Mass number: 107 + 157 = 264 g/mol

Answer:

Explanation:

H

Answer:

8.35 × 10 ²² molecules

Explanation:

gram molecular weight of N2O4

= 2 × 14 + 4 × 16

= 28 + 64

= 92g

1 mole N2O4 has 6 × 10²³ molecules of N2O4 and weighs 92g

therfore,

92 g has = 6 × 10²³ molecules

12.8 g has =

[tex] \frac{6 \times 10 {}^{23}}{92} \times 12.8[/tex]

= 0.835 × 10²³

= 8.35 × 10 ²² molecules

Answer:

d

Explanation:

Answer:

The produced salt is calcium chloride, CaCl₂, whose cation, Ca²⁺, is the conjugate acid of the base and the anion, Cl⁻ the conjugate base of the acid.

Explanation:

Hello there!

In this case, according to the given information, it turns out firstly necessary for us to set up the chemical equation between calcium hydroxide and hydrochloric acid:

[tex]2HCl+Ca(OH)_2\rightarrow CaCl_2+2H_2O[/tex]

It means that the produced salt is calcium chloride, CaCl₂, whose cation, Ca²⁺, is the conjugate acid of the base and the anion, Cl⁻ the conjugate base of the acid.

Regard"

Answer:

Magnesium (Mg)

Explanation:

The elements have very similar properties: they are all shiny, silvery-white, somewhat reactive metals at standard temperature and pressure.

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Thank You

Answer:

The answer is C. Magnesium(Mg)

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Answer:

Lewis structure of polyatomic formate anion.

Explanation:

To draw Lewis structure for any chemical species,

1)Count the total number of valence electrons present in it.

This can be obtained by adding valence electrons of each constituent atom.

2)Arrange those valence electrons in such a way that each atom should attain eight electrons around it to satisfy octet theory.

The structure of formate ion and its Lewis structure are shown below:

HCOO- is the formate ion.

It has total:

1+4+6+6+1 = 18 valence electrons.

Since, hydrogen has one, carbon has four and oxygen has six valence electrons and the charge of the anion is one.

Arrange this 18 electrons in such a way that each atom should get 8 electrons around it.

Resonance structures of formate ion:

Answer:

Oxygen, O₂ is the limiting reactant

Explanation:

We'll begin by writing the balanced equation for the reaction. This is given below:

2H₂ + O₂ —> 2H₂O

Next, we shall determine the masses of H₂ and O₂ that reacted from the balanced equation. This can be obtained as follow:

Molar mass of H₂ = 2 × 1 = 2 g/mol

Mass of H₂ from the balanced equation = 2 × 2 = 4 g

Molar mass of O₂ = 16 × 2 = 32 g/mol

Mass of O₂O from the balanced equation = 1 × 32 = 32 g

SUMMARY:

From the balanced equation above,

4 g of H₂ reacted with 32 g of O₂.

Finally, we shall determine the limiting reactant. This can be obtained as follow:

From the balanced equation above,

4 g of H₂ reacted with 32 g of O₂.

Therefore, 10 g of H₂ will react with

= (10 × 32)/4 = 80 g of O₂.

From the calculations made above, we can see that a higher mass (i.e 80 g) of O₂ than what was given (i.e 5 g) is required to react completely with 10 g of H₂. Therefore, O₂ is the limiting reactant.

Oxygen has been the limiting reactant in the reaction.

A limiting reactant can be defined as the reactant in the reaction in which the product concentration has been dependent.

The balanced equation for the formation of water has been:

[tex]\rm 2\;H_2\;+\;O_2\;\rightarrow\;2\;H_2O[/tex]

For the formation of reaction to form 2 moles of water, 2 moles of hydrogen reacts with 1 mole of oxygen.

The moles can be calculated as:

Moles = [tex]\rm \dfrac{weight}{molecular\;weight}[/tex]

The moles of Hydrogen in 10 g [tex]\rm H_2[/tex]:

Moles = [tex]\rm \dfrac{10}{2}[/tex]

Moles of hydrogen = 5 mol.

Moles of Oxygen in 5 grams Oxygen:

Moles = [tex]\rm \dfrac{5}{32}[/tex]

Moles of oxygen = 0.156 mol.

For the reaction with 2 moles of Hydrogen 1 mole of Oxygen has been required.

For reacting with 5 mol of Hydrogen, moles of oxygen required are:

Moles of oxygen = [tex]\rm \dfrac{1}{2}\;\times\;5[/tex]

Moles of oxygen required = 2.5 moles.

The available oxygen = 0.156 moles.

Since the moles of oxygen available is lesser than required, the formation of the product has been dependent on the concentration of the oxygen.

Thus, oxygen has been the limiting reactant in the reaction.

For more information about the limiting reactant, refer to the link:

https://brainly.com/question/14225536

Answer:

salt and sand

Explanation:it is what it is

Answer:

joib

Explanation:

Answer:

We know that the student was measuring a spectrum, and observed double yellow lines, he claimed that it was Sodium.

There are multiple elements with double yellow lines, like Mercury or Sodium, but Sodium has two bright yellow lines, so it is usually identified by them.

So when we look at a spectrum and we see a strong doublet in the yellow range, we can easily assume that it is Sodium.

Here we assume that the student only saw the yellow doublet, this would imply that the yellow doublet is way more intense than the other lines, that can't be seen (while for other elements with double yellow lines, we should see other lines with similar intensity) then we can conclude that it is Sodium.

The student is correct.

Answer:

Sterilization refers to any process that removes, kills, or deactivates all forms of life and other biological agents like prions present in a specific surface, object or fluid, for example food or biological culture media.

Answer:

both

Explanation:

A homolytic fission is said to have occurred when the breakage of a bond between two atoms leaves each of the bonding atoms with equal number of electrons. Homolytic fission often results in the creation of radicals.

Since homolytic fission yields two species with equal number of electrons(usually odd number of electrons), the products of such process can not be charged. They can not be nucleophiles because nucleophiles need to possess two electrons which can be shared with another chemical specie.

Answer:

The molar mass of N2O5 is 108 g/mol. 1296g of N2O5 has 1296 / 108 = 12 moles. 1 mole contains 6.022 x 10^23 molecules

Answer: 3.4 × 10 -1 equal 33.5 cs. May I have brainiest? pls. (the -1 is to the power of the ten.