What are sublimation, decantation, sedimentation, filtering and sieving?

Sublimation is when a solid transitions into a gas, bypassing the liquid state. An example of this is when solid carbon sublimates into a gas as dry ice.

Decantation is when a mixture of liquids is allowed to separate, such that an element of the mixture may be removed. An example of decantation is when wine or beer is poured slowly to prevent sediments entering the glass with the alcohol.

Sedimentation is when particulates fall out of a mixture. An example is when you scoop up water from a lake or river, and over time a layer of dirt forms on the bottom.

Filtering is when a fluid is passed through a porous filter, picking out the solids in the fluid as it passes by. An example of this is when coffee is placed in a coffee filter, allowing water through but none of the grounds.

Sieving is similar to filtering, but is used to describe the filtering of large particles. An anthropologist would use a sieve to search for artifacts in a pan of dirt.

Give a character sketch of the soldier in the poem, "The Man He Killed" by Thomas Hardy. Describe the soldier's occupation, social class, and level...

The soldier in Thomas Hardy's poem is an infantryman. We see this in the first line of the second stanza, when he says "But ranged as infantry." That means he fights in the military. He also mentions in stanza four that he only enlisted in the military because he was out of work. 

He thought he'd 'list, perhaps, 

            Off-hand like — just as I — 

Was out of work — had sold his traps — 

            No other reason why. 

In that excerpt, we see that the speaker is thinking about the man that he just killed. He wonders if that man joined just because he was out of a job, like the speaker did. The speaker had "no other reason" to join the military.

We can also assume that the speaker is not wealthy, but also not poor. He is not wealthy enough to not work - since he has to join the military when he loses his job. But he also is wealthy enough to be generous; he claims that he would "treat [the man] if met where any bar is, / Or help [him] to half-a-crown." That means that the speaker has enough money to comfortably buy another man a drink, or to give him some money if he needs it.

We can conclude that the speaker is at least decently educated due to his thought process. He is smart enough to question the war and the peculiarity of fighting against someone you might normally buy a drink for. This suggests an inquisitive mind, rather than a complacent mind that accepts the fighting.

Hope this helps!

If a solution of magnesium hydroxide Mg(OH)2 has a concentration of 1.8E-6 M, calculate the concentration of its hydroxide ion.

Magnesium hydroxide is a weak base with low solubility in water. It contains two hydroxide ions (OH-) per formula unit, so the number of hydroxide ions per liter in 1.8 x 10E-6 M solution is:

2(1.8 x 10E-6) = 3.6 x 10E-6.

However, this doesn't technically answer the question, as most of these hydroxide ions will not have dissociated from the magnesium ions due to the compound's low solubility. To calculate the concentration of dissociated OH- ions in solution we need to know the Ksp (solubility product constant) for magnesium hydroxide. This value is 5.6 x 10E-12 at 25ºC.

Here's what the Ksp value means: The amount of magnesium hydroxide that dissolves will be such that the product of the magnesium ion and hydroxide ion concentrations in solution, raised to the power of their coefficients, will be equal to 5.6 x 10E-12:

`Mg(OH)_2 -> Mg^(2+) + 2 OH^-`

`[Mg^(2+)][OH^-]^2 = K_(sp) = 5.6 x 10^(-12)`

Since there are twice as many dissolved hydroxide ions as magnesium ions (based of the formula of magnesium hydroxide) we can say that [Mg(2+)] = X and [OH-] = 2X, then solve for [OH-]:

`(X)(2X)^2 = 5.6 x 10^(-12)`

`4X^3 = 5.6 X 10^(-12)`

`X = 1.12 x 10^(-4)`

`[OH-] = 2X = 2.22 x 10^(-4) M`

Was World War II just?

When deciding if something is just, we are dealing with an opinion. For this question, the answer might be very different if looked at from the Japanese point of view rather than from the American point of view. I will explain why some people say, and not all Americans will agree, that World War II was just.

As World War II approached, the rise of countries with dictatorships or non-democratically elected governments was growing. These governments had become very aggressive and began to conquer other countries against their will. If there is one thing that World War II taught us, it is that aggressive actions can’t be ignored. Thus, the Allies were correct to eventually step in when Germany invaded Poland.

From the American point of view, it made a lot of sense to support Great Britain. Their government and way of life were similar to our government and way of life. We had more in common with Great Britain than with Germany, Japan, and Italy. Once we were attacked at Pearl Harbor, we had to enter the war. We couldn’t let another country attack us without a response. At that point in time, we needed to do whatever we needed to do to win the war and to save as many American lives as possible in the process of winning the war. Thus, the decision to use the atomic bomb could be viewed as a just decision because it potentially saved one million American soldiers from being hurt or killed in a potential invasion of Japan.

The fight to maintain freedom and democracy is a just fight. Winning a war and saving as many American lives as possible is also very just. Thus, World War II was a just war.

What does Doon ask Lina, and what explanation does Lina give for taking Poppy in Jeanne DuPrau's The City of Ember?

In Chapter 17 of Jeanne DuPrau's The City of Ember, Doon, Lina, and Poppy make it safely in boats through the wild river ride to a walled off pool of water. They then pull to the edge of the pool where there is a rocky slope, and Lina, wading ashore to explore, finds a path to follow. But before they follow the path, they stop to eat. It is at this point that Doon says to Lina, "I saw the guards run after you. Tell me what happened. ... And what about Poppy? What did you tell Mrs. Murdo?"

Lina then explains how she was caught by and escaped from the guards and that, while waiting for the lights to come back on, she made the decision not to leave without Poppy. She further explains she "told [Mrs. Murdo] the truth," or what Lina hopes is the truth, which is that Lina is taking Poppy to safety. Before the lights went out for the longest time, Lina had thought leaving Poppy with Mrs. Murdo would be the safest thing to do, at least for a time. But, while standing on the roof of the Gathering Hall, waiting for what seemed like an eternity for the lights to come back on, Lina had realized the following:

There is no safety in Ember. Not for long. Nor for anyone. I couldn't leave her behind. Whatever happens to us now, it's better than what's going to happen there. (Ch. 17)

In other words, though Lina had thought differently at first, Lina had realized Ember was too much in peril to leave Poppy safely behind. Even though making the journey was more difficult with Poppy, she knew taking Poppy along was the right thing to do.

How would I approach writing a news article about the mad dog incident in To Kill a Mockingbird? You are a Maycomb reporter and just witnessed...

A newspaper article focuses on answering basic questions and providing information.  Who was there? What happened and when did it happen?  Where did it happen? Why did it happen? How did it happen?  In this case, you probably want to focus on answering these questions because you only have two paragraphs to write your article.  Pretend that you are actually there, witnessing the event.

What happened, when and why: A rabid dog threatened Maycomb.  The dog, Tim Johnson, had contracted rabies and was seen walking down the street.  It is unusual to see a mad dog in February, and everyone is nervous.  The mad dog is contagious to people.  Sheriff Heck Tate is called.

Where it happened: The incident occurred on Maycomb’s main residential street.  The dog was finally confronted and shot in front of the Radley house.

Who was there: The main players in this event are Atticus Finch and Heck Tate.  Atticus is the one who shot the dog, and Heck Tate is the one who insisted he do it.  A good newspaper article might include a quote, such as what Heck Tate said to Atticus.

“Mr. Finch, this is a one-shot job.”

Atticus shook his head vehemently: “Don’t just stand there, Heck! He won’t wait all day for you—”

“For God’s sake, Mr. Finch, look where he is! Miss and you’ll go straight into the Radley house! I can’t shoot that well and you know it!” (Ch. 10)

A human-interest angle would also be good to include.  You might want to mention that Mr. Finch’s two children, Atticus and Jem, were watching their father shoot the dog.  The children and everyone else in the street were in danger. 

All of the neighbors were watching too, including Miss Stephanie Crawford and Miss Maudie.  The trash man, Zeebo, collected the dog afterward.  He made sure no one else touched it, because a mad dog is just as dangerous dead as alive.

What does Hamlet stalling killing Claudius say about Hamlet's approach to revenge? Does his approach change the genre of the play from merely a...

I don't know that Hamlet has ever been merely a "revenge" play. While avenging his father's death is Hamlet's motivating impulse for the plot, the play has always been about the internal struggle Hamlet wrestles with, and the larger thematic implications that result.

Hamlet vows on several occasions to kill Claudius, and his determination seems sincere. He tells his father's ghost, "thy commandment [to kill Claudius] all alone shall live within the book and volume of my brain," and he promises that his "thoughts be bloody or be nothing worth." Nonetheless, he first decides to test the ghost's word by setting up the play-within-the-play, and later passes up the opportunity to kill Claudius while he prays, choosing not to "take him in the purging of his soul." This brings the ghost back to remind Hamlet to fulfill his "almost blunted purpose." Hamlet still does not act, instead choosing to procrastinate and make excuses.

What this says about Hamlet isn't so much about his "approach to revenge" as it is about his reluctance to murder his mother's lover. Oedipal interpretations aside, doing so would mean Hamlet would, in all likelihood, estrange himself from his mother, to whom he is deeply devoted. Worse, it would mean Hamlet himself would assume the throne and all its attendant responsibilities. Hamlet's a college student who wants to return to Wittenburg and resume his studies. The idea of ruling Denmark and filling the kingly shoes of his great father is probably pretty intimidating. Moreover, killing Claudius is an act Hamlet presumably has difficulty stomaching. He's only able to kill Polonius when he's hiding behind an "arras," where Hamlet doesn't have to face him. Murdering Claudius would most likely be a more intimate act, and one that the creative and romantic Hamlet may lack the willpower to commit. His contemplation of suicide in both of his early soliloquies suggests Hamlet may prefer to orchestrate his own death than his uncle's, so conflicted is he about his responsibility to his father and country.  

Ultimately, Hamlet doesn't kill himself, either. Instead, he feigns madness, orchestrates a play, toys with Ophelia's heart, aggravates Polonius, and duels Laertes. Hamlet, quite simply, doesn't know what to do. In spite of the obligation he has taken on, Hamlet seemingly lacks the resolve to fulfill it. Thus, the play is more about the existential questions he raises as he wrestles with his conscience: do our actions on earth even matter? Is death preferable to life? Are we merely waiting to become "clay [to] stop a hole and keep the wind away"? The revenge aspect of Hamlet is merely the vehicle by which Shakespeare introduces his larger and more far-reaching themes, and this is at least partly responsible for its timeless and enduring appeal.