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E. solid copper sulfide and silver nitrate react to form copper (ii) nitrate and solid silver sulfide. write a balanced chemical equation that describes the reaction. identify the oxidation number of each element in the reaction. (you do not need to include the total contribution of charge.) is this reaction a redox reaction or a non-redox reaction? explain your answer.

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Answer:

The given reaction is not a redox reaction.

Explanation:

Redox reaction is defined as chemical reaction in oxidation and reduction reactions occurs simultaneously.

Oxidation reaction is defined as the reaction in which an atom looses its electrons. Here, oxidation state of the atom increases.

Reduction reaction is defined as the reaction in which an atom gains electrons. Here, oxidation state of the atom decreases.

Solid copper sulfide when immersed in silver nitrate solution it reacts to form silver sulfide precipitate and copper(II) nitrate solution.

CuS(s)+2AgNO_3(aq)rightarrow Cu(NO_3)_2(aq)+Ag_2S(s)

Oxidation states of elements on reactant side:

Oxidation state of copper  = +2

Oxidation state of sulfur = -2

Oxidation number of silver  +1

Oxidation number of nitrogen = +5

Oxidation number of oxygen = -2

Oxidation states of elements on product side:

Oxidation state of copper  = +2

Oxidation state of sulfur = -2

Oxidation number of silver  +1

Oxidation number of nitrogen = +5

Oxidation number of oxygen = -2

No change in oxidation states of elements is observed which means that the given reaction is not a redox reaction.

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Different ______ of an element have different numbers of electrons.1.ions2.isotopes3.compounds4.atoms

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Answer: 1. Ions

Explanation: Ions of an element are formed when an atom lose or gain electrons and thus different ions will have different electrons.

For example Na^+ with 10 electrons is formed when Na with 11 electrons loses one electron. Na^- with 12 electrons is formed when Na with 11 electrons gains one electron.

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The chemical formula of lithium carbonate is Li2CO3. Which statement below best describes the types and number of atoms of each element making up this substance? A. Two lithium atoms; one calcium atom; one oxygen atom B. One lithium atom; three carbon atoms; three oxygen atoms C. One lithium atom; one carbon atom D. Two lithium atoms; one carbon atom; three oxygen atoms

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The chemical formula of lithium carbonate is Li2CO3. Which statement below best describes the types and number of atoms of each element making up this substance? A. Two lithium atoms; one calcium atom; one oxygen atom B. One lithium atom; three carbon atoms; three oxygen atoms C. One lithium atom; one carbon atom D. Two lithium atoms; one carbon atom; three oxygen atoms

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What are the element represented by [He]2s2

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What are the element represented by [He]2s2

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What is this element 1s22s22p6?

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What is this element 1s22s22p6?

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What Supernatural element does Shakespeare use to surprise the reader In this passage

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What Supernatural element does Shakespeare use to surprise the reader In this passage

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Which of the following did Antoine Lavoisier correctly characterize as an element?

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Answered by answersmine AT 22/10/2019 – 03:48 AM

I think the element that has been correctly defined by Antoine Lavoisier would be the element oxygen. He is famous for the discovery of the importance of the molecule oxygen in the process of combustion. He is is the one who characterized and named the element oxygen and hydrogen. Also, showing how these atoms combine in order to form a water molecule in the combustion process. He is considered as the father of modern chemistry as he helped in organizing nomenclature of the chemical compounds. He also is responsible for laying the foundations of the famous law of conservation of mass. 

Post your answer

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Which supernatural element described In this passage helps build tension by foreshadowing future events

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Which supernatural element described In this passage helps build tension by foreshadowing future events

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What is the term for the amount of time it takes 50% of an element to decay

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What is the term for the amount of time it takes 50% of an element to decay

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What is the term for the amount of time it takes 50 % of an element to decay?

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What is the term for the amount of time it takes 50 % of an element to decay?

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Read the excerpt from Cristina Garcia’s Dreaming in Cuban. My father knew I understood more than I could say. He told me stories about Cuba after Columbus came. He said that the Spaniards wiped out more Indians with smallpox than with muskets. Which best describes an element of magic realism used by Garcia in this excerpt? She shows the close relationship that Pilar had with her father. She connects the events to the colonial history of Latin America. She is a modern writer developing a story about Spanish history. She characterizes Columbus’s discovery as an extraordinary event.

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Read the excerpt from Cristina Garcia’s Dreaming in Cuban. My father knew I understood more than I could say. He told me stories about Cuba after Columbus came. He said that the Spaniards wiped out more Indians with smallpox than with muskets. Which best describes an element of magic realism used by Garcia in this excerpt? She shows the close relationship that Pilar had with her father. She connects the events to the colonial history of Latin America. She is a modern writer developing a story about Spanish history. She characterizes Columbus’s discovery as an extraordinary event.

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What element would you get if three protons were added to Lithium?

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25) Answer is: less metallic and more nonmetallic.

Electronegativity increases from left to right across a period, atoms have tendency to attract electrons.

Electronegativity (χ) is a property that describes the tendency of an atom to attract a shared pair of electrons.

26) Answer is: radioisotope.

Radioisotope has an unstable atomic nucleus and emit energy and particles when it changes to a more stable form.

Francium (Fr) is element with atomic number 87 (87 protons and 87 electrons).

27) Answer is: boils.

Boiling is the temperature at which the vapour pressure of the liquid is equal to the pressure exerted on the liquid by the surrounding atmosphere.

The Celsius scale was based on 0°C for the freezing point of water and 100°C for the boiling point of water at 1 atm pressure.

28) Answer is: endothermic.

There are two types of reaction:  

1) endothermic reaction (chemical reaction that absorbs more energy than it releases, ΔH>0).

2) exothermic reaction (chemical reaction that releases more energy than it absorbs).  

For example, the breakdown of ozone is an endothermic process. Ozone has lower energy than molecular oxygen (O₂) and oxygen atom, so ozone need energy to break bond between oxygen atoms.  

29) Answer is: kinetic.

The average kinetic energy of molecules depends on the temperature.  

As temperature increases, molecules gain more energy from surrounding and move faster.  

Kinetic energy (standard unit is the joule J) depends on speed of the molecule.  

Solid gains kinetic energy to become a liquid and then becomes a gas.

30) Answer is: alpha particles.

This was famous Rutherford’s Gold Foil Experiment: he bombarded thin foil of gold with positive alpha particles.

Rutherford observed the deflection of alpha particles on the photographic film.  

Alpha particles are helium atom particles, consist of two protons and two neutrons.  

According to Rutherford model of the atom: atoms have their charge concentrated in a very small nucleus.  

31) Answer is: highest.

For example, calcium oxide.

Calcium oxide (CaO) has ionic bonds between calcium cations (Ca²⁺) and oxygen anions (O²⁻).

Because it has strong ionic bonds, it has high melting point (around 2600°C).

Ionic bond is the electrostatic attraction between oppositely charged ions (cations and anions).

32) Answer is: a scientific model.

A scientific model is a representation of an idea, an object, a process or a system that is used to describe and explain phenomena that cannot be experienced directly.

33) Answer is: the superscript is mass number and the subscript is atomic number.

Atomic number(Z) is the number of protons, which is characteristic of a chemical element..

Mass number (A) is the total number of protons and neutrons in a nucleus.

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Visit this website and locate the element mercury, whose chemical symbol is Hg. Click on the square to read about the history, properties, and uses of mercury. Name three uses for mercury.

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Visit this website and locate the element mercury, whose chemical symbol is Hg. Click on the square to read about the history, properties, and uses of mercury. Name three uses for mercury.

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Stacey is writing a literary analysis essay on a play. What approach should she take to write a strong essay Stacey should (Examine each element of the play) or (focus on the plot) and (develop the central idea for the essay) or (write a summary of the plot)

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Here are a few pointers; hope this is useful)

Ovation-by definition- is show of appreciation from an audience, for a person’s accomplishments or flaw.

“Everyone deserves a standing ovation because we all overcometh the world.”

A person’s accomplishment could be how they made a positive change in this world, strong leadership- that makes them a effective leader or simply helping others. A person’s flaw- mistakes in life, sin or even guilt should also be considered an appreciation- an ovation for representing mankind’s flaw and that humanity makes mistakes, fulfilling at least one deadly sin such as greed, lust, selfishness etc.

Thus, regardless of a person’s achievement or flaw- a person deserves an applause for, not the least, living in this society and this world that we are all living together and dying together.

That was just the introduction.. the best part is yet to come.. now it’s your turn!!

Here are other pointers to talk about in your essay:

Shakespeare’s famous line “All the World’s a stage. That agrees with your line: “Everybody deserves a standing ovation…”

Shakespeare explains that men and women are like players: they live, and die, some being celebrated and some forever living in solitude till their death. Shakespeare states the world is a “stage” which symbolizes that mankind is in its peak. The world is changing everyday: little by little and humanity is falling behind.
Due to our world turning into machinery: factories, an automotive future: where humans only job to live (entrance) and to die (exit) the famous humans remembered and the flawed not recalled.

This is according to Shakespeare’s imagery.

I don’t know what grade your in, but I think simplifying Shakespeare’s word of mouth in your essay would be handy and useful as it has strong references of your quote, and agrees strongly in your essay.

Hope this helps 🙂

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All atoms of the element potassium have 19 protons. One of the most stable types of potassium atoms has the mass number 39. How many neutrons make up one of these potassium atoms? -19 -20 -38 -58

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The unknown of this problem is the experimental percent of water in the compound in order to remove the water of hydrogen, given the following:

Mass of crucible, cover and contents before heating                               23.54 g
Mass of empty crucible and cover                                                            18.82 g
Mass of crucible, cover, and contents after heating to constant mass     20.94 g

In order to get the answer, determine the following:

Mass of hydrated salt used                          = 23.54 g – 18.82 g = 4.72 g
Mass of dehydrated salt after heating          = 20.94 g – 18.82 g = 2.12 g
Mass of water liberated from salt                 = 4.72 g – 2.12 g = 2.60 g

Then solve the percent of water in the hydrated salt by:

% water = (mass of water / mass of hydrated salt) x 100
% water = 2.60 g / 4.72 g x 100
% water = 55.08 % in the compound 

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Combustion analysis of an unknown compound provides the following data: 73.5 grams carbon (C), 4.20 grams hydrogen (H) and 72.3 grams chlorine (Cl). What is the percent composition of each element in this compound?

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This problem is to apply Roult’s Law.

Roult’s Law states that the vapor pressure, p, of a solution of a non-volatile solute is equal to the vapor pressure of the pure solvent, Po solv, times the mole fraction of the solvent, Xsolv

p = Xsolv * Po sol

X solv = number of moles of solvent / number of moles of solution

The solvent is water and the solute (not volatile) is glycerin.

Number of moles = mass in grams / molar mass

mass of water = 132 ml * 1 g/ml = 132 g

molar mass of water = 18 g/mol

=> number of moles of water = 132 g / 18 g/mol = 7.33333 mol

mass of glycerin = 27.2 g

molar mass of glycerin:, C3H8O3: 3 * 12 g/mol + 8 * 1 g/mol + 3*16 g/mol = 92 g/mol

number of moles of glycerin = 27.2g / 92 g/mol = 0.29565

total number of moles = 7.33333 moles + 0.29565 moles = 7.62898 moles

=> X solv = 7.33333 / 7.62898 = 0.96125

=> p = 0.96125 * 31.8 torr ≈ 30.57 torr ≈ 30.6 torr.

Answer: 30.6 torr

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Changing the sentence structure and how quickly events unfolds in a story can affect such literary element

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Changing the sentence structure and how quickly events unfolds in a story can affect such literary element

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At the turn of the century, the french academy was divided rather sharply between two doctrines. one taught form (including line and drawing) was the most important element in the painting and the other taught that color was the most important element. which doctrine did the rococo artist follow?

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-From a article I have read.-

As a literary genre, a memoir (from the French: mémoire from the Latin memoria, meaning “memory”), or a reminiscence, forms a subclass of autobiography – although the terms ‘memoir’ and ‘autobiography’ are today almost interchangeable. The author of a memoir may be referred to as a memoirist.

***Nature of Memoirs***

Memoirs may appear less structured and less encompassing than formal autobiographical works as they are usually about part of a life rather than the chronological telling of a life from childhood to adulthood/old age. Traditionally, memoirs usually dealt with public matters, rather than personal, and many older memoirs contain little or no information about the writer, and are almost entirely concerned with other people. They tended to be written by politicians or people in court society, later joined by military leaders and businessmen, and often dealt exclusively with the writer’s careers rather than their private life. Modern expectations have changed this, even for heads of government. Like most autobiographies, memoirs are generally written from the first person point of view.

Gore Vidal, in his own memoir Palimpsest, gave a personal definition: “a memoir is how one remembers one’s own life, while an autobiography is history, requiring research, dates, facts double-checked.” It is more about what can be gleaned from a section of one’s life than about the outcome of the life as a whole.

Contemporary practices of writing memoirs for recreational, family or therapeutic purposes are sometimes referred to as legacy writing or personal history. Such products may be assisted by professional or amateur genealogists, or by ghostwriters.

***Types of Memoir***

Memoirs have often been written by politicians or military leaders as a way to record and publish an account of their public exploits. In the eighteenth century, “scandalous memoirs”, allegedly factual but largely invented, were written (mostly anonymously) by prostitutes or libertines: these were widely read in France for their vulgar details and gossip. In another vein, the pagan rhetor Libanius framed his life memoir as one of his orations, not the public kind, but the literary kind that would be read aloud in the privacy of one’s study. This kind of memoir refers to the idea in ancient Greece and Rome, that memoirs were like “memos,” pieces of unfinished and unpublished writing which a writer might use as a memory aid to make a more finished document later on.

Women writers have been prominent amongst those combining the memoir form with historical non-fiction writing. Examples include Jung Chang’s Wild Swans. Maxine Hong Kingston’s book The Woman Warrior is an example of a memoir that combines factual material with fictional material as it tells the author’s story and the story of her family.

Some professional contemporary writers such as David Sedaris and Augusten Burroughs have specialised in writing amusing essays in the form of memoirs. To some extent this is an extension of the tradition of newspaper columnists’ regular accounts of their lives. (Cf. the work of James Thurber which often has a strong memoir-like content).

Another category of memoir is the eyewitness account of history by onlookers to major events or particular eras; Slave narratives (e.g. the memoirs of Frederick Douglass) fall into this category as do those by Primo Levi and Elie Wiesel.

I hope this Helps! Sorry for the delay, enjoy your day!!✨✨✨

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An atom of the element iron has an atomic number of 26 and an atomic mass number of 56. if it is neutral, how many protons, neutrons, and electrons does it have?

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The unknown of this problem is the experimental percent of water in the compound in order to remove the water of hydrogen, given the following:

Mass of crucible, cover and contents before heating                               23.54 g
Mass of empty crucible and cover                                                            18.82 g
Mass of crucible, cover, and contents after heating to constant mass     20.94 g

In order to get the answer, determine the following:

Mass of hydrated salt used                          = 23.54 g – 18.82 g = 4.72 g
Mass of dehydrated salt after heating          = 20.94 g – 18.82 g = 2.12 g
Mass of water liberated from salt                 = 4.72 g – 2.12 g = 2.60 g

Then solve the percent of water in the hydrated salt by:

% water = (mass of water / mass of hydrated salt) x 100
% water = 2.60 g / 4.72 g x 100
% water = 55.08 % in the compound 

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Read the passage. From “The First Seven Years” by Bernard Malamud “Thanks,” Max said, nervously alert. He was tall and grotesquely thin, with sharply cut features, particularly a beak-like nose. He was wearing a loose, long slushy overcoat that hung down to his ankles, looking like a rug draped over his bony shoulders, and a soggy, old brown hat, as battered as the shoes he had brought in. Identify the plot element in this passage.

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Well; You have the classics

1984, you might have been asked to read this one already in school, if not I suggest going ahead and reading it; its fun to be ahead of your class. 

Originally published in 1949 by George Orwell, 1984 depicts a dystopian world of the ‘future’. The book is less of a prediction more then it is a warning of what could be. It follows one character who is desperately trying to remember what real life is like, and gets tangled up in all sorts of messes along the way.

You could read Alice in Wonderland or Mary Poppins, theres a million great classics out there Im sure you can find on any website. 

Personally I prefer fantasy novels; 

Brandon Sanderson’s The Rithmatist 
This book follows a young student through a steampunk style, magic infused world. It takes a moment to not chuckle at the concept of monsters that are essentially drawings, but its a very well done book with beautiful writing and mental scenery 

Patrick Rothfuss’s, The Name of the Wind 
This is my favorite book of all time. Patrick Rothfuss’s work is honestly amazing in this book. Mind you its probably not all that wise for the feint of heart through perhaps the second chapter; but it really is amazing. The sculpting of the world, the depth of the characters its utterly masterful. The story opens with Kote, a fairly normal seeming innkeeper and his dark haired companion Bast. Fairly normal until a man happens upon the inn, looking for a certain Kvothe, a man thought to just be a legend and a story… and Kote’s past is drug up, and other things that should probably be better left alone.

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Which of the following best predicts the outcome of a fusion reaction involving isotopes of hydrogen?Two hydrogen isotopes form bonds with each other, absorbing a large amount of energy.The nuclei of the hydrogen isotopes join together to form a heavier element, and energy is released.Isotopes of hydrogen absorb electrons, undergo an increase in energy level, and split into fragments.The nuclei of the hydrogen isotopes split, resulting in smaller fragments and the release of a large amount of energy.

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The balanced chemical reaction is as shown below,

                 N₂ + 3H₂  –> 2NH₃

The equation shows that every 3 moles of hydrogen, H2, there would be 2 moles of ammonia, NH3, that is going to be formed. Using this concept, we solve for the unknown in this item. 

Since we are restricted only of the number of hydrogen, it becomes our limiting reactant. 

          (6 moles H2) x (2 moles NH3/3 moles H2) = 4 moles NH3

Therefore, given enough amount of N2, the amount of NH3 that can be formed out of the 6 moles of H2 is equal to 4 moles. 

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All of the following are examples of the environment element of the six essential elements of geography except. A.setting in a region with a mild, predictable climateB. constructing dams to prevent floodingC. building a house made of mud in a hot, dry areaD. trading with other societies for scarce Goods

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Such diverse historical figures as Jesus Christ, napoleon, Julius Caesar, Adolf Hitler, Winston Churchill, Franklin Roosevelt, Martin Luther King, Jr., and Cesar Chavez, are examples of Charismatic leaders. The reason is that they were able to inspire and motivate many followers. They were all good communicators and convinced the audience about their ideas and opinions.

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You are trying to determine the half-life of a new radioactive element you have isolated. You start with 1 gram, and 5 days later you determine that it has decayed down to 0.7 grams. What is its half-life? (Round your answer to three significant digits.)

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You need to determine the number of ways in which 30 competitors from 50 can qualify. First, you have to realize that the order is irrelevant, that is: it is the same competitor_1, competitor _2, competitor _3 than competitor_3, competitor_2, competitor_1, or any combination of those three competitors.

So, the number of ways is which 30 competitors from 50 can qualify is given by the formula of combinations, which is:

C (m,n) = m! / (n! * (m -n)! )

=> C (50,30) = 50! / (30! (50 – 30)! ) = (50!) / [30! (50 – 30)!] = 50! / [30! 20!] =

 = 47,129,212,243,960 different ways the qualifiying round of 30 competitors can be selected from the 50 competitors.

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He atomic mass of an element is equal to ________. its mass number its atomic number one-twelfth of the mass of a carbon-12 atom the mass of an “average atom” the mass of the heaviest isotope

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The unknown of this problem is the experimental percent of water in the compound in order to remove the water of hydrogen, given the following:

Mass of crucible, cover and contents before heating                               23.54 g
Mass of empty crucible and cover                                                            18.82 g
Mass of crucible, cover, and contents after heating to constant mass     20.94 g

In order to get the answer, determine the following:

Mass of hydrated salt used                          = 23.54 g – 18.82 g = 4.72 g
Mass of dehydrated salt after heating          = 20.94 g – 18.82 g = 2.12 g
Mass of water liberated from salt                 = 4.72 g – 2.12 g = 2.60 g

Then solve the percent of water in the hydrated salt by:

% water = (mass of water / mass of hydrated salt) x 100
% water = 2.60 g / 4.72 g x 100
% water = 55.08 % in the compound 

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2CO + 2NO yields 2CO2 + N2 which element was oxidized

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25) Answer is: less metallic and more nonmetallic.

Electronegativity increases from left to right across a period, atoms have tendency to attract electrons.

Electronegativity (χ) is a property that describes the tendency of an atom to attract a shared pair of electrons.

26) Answer is: radioisotope.

Radioisotope has an unstable atomic nucleus and emit energy and particles when it changes to a more stable form.

Francium (Fr) is element with atomic number 87 (87 protons and 87 electrons).

27) Answer is: boils.

Boiling is the temperature at which the vapour pressure of the liquid is equal to the pressure exerted on the liquid by the surrounding atmosphere.

The Celsius scale was based on 0°C for the freezing point of water and 100°C for the boiling point of water at 1 atm pressure.

28) Answer is: endothermic.

There are two types of reaction:  

1) endothermic reaction (chemical reaction that absorbs more energy than it releases, ΔH>0).

2) exothermic reaction (chemical reaction that releases more energy than it absorbs).  

For example, the breakdown of ozone is an endothermic process. Ozone has lower energy than molecular oxygen (O₂) and oxygen atom, so ozone need energy to break bond between oxygen atoms.  

29) Answer is: kinetic.

The average kinetic energy of molecules depends on the temperature.  

As temperature increases, molecules gain more energy from surrounding and move faster.  

Kinetic energy (standard unit is the joule J) depends on speed of the molecule.  

Solid gains kinetic energy to become a liquid and then becomes a gas.

30) Answer is: alpha particles.

This was famous Rutherford’s Gold Foil Experiment: he bombarded thin foil of gold with positive alpha particles.

Rutherford observed the deflection of alpha particles on the photographic film.  

Alpha particles are helium atom particles, consist of two protons and two neutrons.  

According to Rutherford model of the atom: atoms have their charge concentrated in a very small nucleus.  

31) Answer is: highest.

For example, calcium oxide.

Calcium oxide (CaO) has ionic bonds between calcium cations (Ca²⁺) and oxygen anions (O²⁻).

Because it has strong ionic bonds, it has high melting point (around 2600°C).

Ionic bond is the electrostatic attraction between oppositely charged ions (cations and anions).

32) Answer is: a scientific model.

A scientific model is a representation of an idea, an object, a process or a system that is used to describe and explain phenomena that cannot be experienced directly.

33) Answer is: the superscript is mass number and the subscript is atomic number.

Atomic number(Z) is the number of protons, which is characteristic of a chemical element..

Mass number (A) is the total number of protons and neutrons in a nucleus.

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