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3 years ago

You have 0.21 moles of Al how many atoms do you have

Chemistry

1 answer:

ZanzabumX [31]3 years ago

8 0

Number of atoms : 1.26 x 10²³

<h3>Further explanation </h3>

The mole is the number of particles(molecules, atoms, ions) contained in a substance

1 mol = 6.02.10²³ particles

Can be formulated

N=n x No

N = number of particles

n = mol

No = Avogadro's = 6.02.10²³

0.21 moles of Al, so n = 0.21

Number of atoms :

$\tt N=0.21\times 6.02\times 10^{23}\\\\N=1.26\times 10^{23}$

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How many liters of fluorine gas, at standard temperature and pressure, will react with 23.5 grams of potassium metal? Show all o

Sladkaya [172]

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Read 2 more answers

Which of the following sign does not indicate that a chemical change has happened .

Sever21 [200]

Answer:

A.)

Explanation:

A change in state may seem like a chemical reaction, but it is actually a physical change. "A change in state" is basically saying that the appearance of whatever the item is, is taking a change physically. Whether this item was going through some examples of a physical change, which would be:

<em>melting (solid to liquid), evaporation (liquid to gas), condensation (gas to liquid), freezing (liquid to solid), deposition (gas to solid), and sublimation (solid to gas).</em>

A change in color, odor, taste, chemical compound, and temperature all represent a chemical reaction, because these are all things that are happening within the the item that is being given the product of a chemical change.

Think of it this way: <em>internal changes within the product: chemical. External changes within the product: physical.</em>

I hope this helps.

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3 years ago

If acetic acid is the only acid that vinegar contains (ka=1.8×10−5), calculate the concentration of acetic acid in the vinegar.

kicyunya [14]

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Solve for x to get the required concentration.

note: 1.)Since you need the answer in 2SF don&t round up values in the middle of the calculation like I've done here.

2.) The ICE (Initial, Change, Equilibrium) table may come in handy if you are new to problems of this kind

Hope this helps!

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