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3 years ago

How many Al atoms are there in 40.5 g of Al foil? Al:27

Chemistry

1 answer:

andrew-mc [135]3 years ago

4 0

Answer:

c) 9.03 x 10^23

Explanation:

find the molar mass of Al

Al is 27.0 grams

Then use that, to find the number of moles in Aluminum.

Then use Avogadro's number which is 6.02 * 10^23

After that, write all of that down with dimensional analysis.

40.5 g * 1 mol/ 27.0 g of Al * 6.02 x 10^23 / 1mol

As your final answer, you will get 9.03 * 10^23 atoms with sig figs.

Hope it helped!

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Is the molecule shown polar or nonpolar f-o-f

SashulF [63]

It's polar because electronegativities of F and O are different.

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3 years ago

If the total population of Asian women was 5000in the 2008 how many females suffered a stroke?

Finger [1]

Answer:

Hi there!

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Explanation:

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3 years ago

What mass of silver can be plated onto an object in 33. 5 minutes at 8. 70 a of current? ag (aq) e- → ag(s) 19. 6 g 9. 78 g 0. 3

grandymaker [24]

Mass of silver can be plated onto an object in 33. 5 minutes at 8. 70 a of current is 19.55 g

Given, I=8.70A, t=33.5min=33.5*60=2010 sec, m of Ag = 19600g M=107.87 g/mol

From faradays law we can write q=I*t= 8.70*2010=17487 C.

moles of Ag =17487/ 19600=0.1812 moles

Ag deposited = 0.1812*107.87 = 19.55 g

<h3>Silver </h3>

Having the atomic number 47 and the Latin word argentum, which means "bright" or "white," silver is a chemical element. Its symbol is Ag. The highest electrical, thermal, and reflectivity of any metal are displayed by this transition metal, which is soft, white, and lustrous. The metal can be found in the Earth's crust in three different forms: as an alloy with other metals like gold and in minerals like argentite and chlorargyrite. It can also be found in its pure, free elemental form, also known as "native silver." During the refining of copper, gold, lead, and zinc, the majority of silver is created as a byproduct. As a valuable metal, silver has long been treasured.

What mass of silver can be plated onto an object in 33. 5 minutes at 8. 70 a of current? ag (aq) e- → ag(s) 19. 6 g 9. 78 g 0. 326 g 3. 07 g 0. 102 g

Learn more about Silver here:

brainly.com/question/14587716

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4 0

2 years ago

A solution prepared by dissolving 0.100 mole of propionic acid in enough water to make 1.00 L of solution is observed to have a

torisob [31]

Answer:

C) $k_a=1.3\times 10^{-5}$

Explanation:

pH is defined as the negative logarithm of the concentration of hydrogen ions.

Thus,

pH = - log [H⁺]

The expression of the pH of the calculation of weak acid is:-

$pH=-log(\sqrt{k_a\times C})$

Where, C is the concentration = 0.5 M

Given, pH = 2.94

Moles = 0.100 moles

Volume = 1.00 L

So, $Molarity=\frac{Moles}{Volume}=\frac{0.100}{1.00}\ M=0.100\ M$

C = 0.100 M

$2.94=-log(\sqrt{k_a\times 0.100})$

$\log _{10}\left(\sqrt{k_a0.1}\right)=-2.94$

$\sqrt{0.1}\sqrt{k_a}=\frac{1}{10^{2.94}}$

$k_a=1.3\times 10^{-5}$

4 0

3 years ago

almunium has a density of 2.70g/cm3. how many moles of aluminium are in a 13.2cm3 block of the metal substances?

skad [1K]

Answer:

1.32 moles.

Explanation:

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

Density of Al = 2.70 g/cm³

Volume of Al = 13.2 cm³

Number of mole of Al =.?

Next, we shall determine the mass of Al.

This can be obtained as follow:

Density of Al = 2.70 g/cm³

Volume of Al = 13.2 cm³

Mass of Al =?

Density = mass / volume

2.7 = mass of Al / 13.2

Cross multiply

Mass of Al = 2.7 × 13.2

Mass of Al = 35.64 g

Finally, we shall determine the number of mole of Al. This can be obtained as follow:

Mass of Al = 35.64 g

Molar mass of Al = 27 g/mol

Number of mole of Al =?

Mole = mass / molar mass

Number of mole of Al = 35.64 / 27

Number of mole of Al = 1.32 moles

Thus, 1.32 moles of aluminum are present in the block of the metal.

7 0

3 years ago