All categories

4 years ago

Em 150 gramas de alumínio, quantos átomos deste elemento estão presentes?

1 answer:

6 0

The question in English:
In 150 grams of aluminum, how many atoms of this element are present?

Data: MM (AI) = 27 g mol-1

Number of avogadro = 6.02 x 10²³

Answer:

Moles (mol) = mass (g) / molar mass (g/mol)

Mass of Al is given as 150 g.
Hence, moles of Al = 150 g / 27 g/mol = 5.56 mol

According to the Avogadro number, 1 mole of substance has 6.02 x 10²³ of particles.

Hence, 1 mole of Al = 6.02 x 10²³ of Al atoms
Then, atoms in 5.56 mol of Al = 6.02 x 10²³ mol⁻¹ x 5.56 mol
= 3.34712 x 10²⁴

Hence, 150 g of Al have 3.34712 x 10²⁴ of atoms.

You might be interested in

1. Explain how groups 1A-8A in the periodic table are organized by their number of valence electrons.

nirvana33 [79]

Explanation:

1. Explain how groups 1A-8A in the periodic table are organized by their number of valence electrons.

The valence electrons in an atom are the outermost shell electrons. They are the most loosely held electrons in an atom.

Coincidentally, the periodic table of elements divided into vertical groups and horizontal periods can be said to be arranged according to the number of valence electrons.

Atomic numbers are used to arrange elements on the periodic table.
Down a group, the number of electronic shell increases. More electrons are added to new energy levels.
As we move from left to right across a period, the number of electrons in elements increases but electronic shell is the same.
Down a group electronic shell increases but the number of valence electrons are the same.
All elements in Group 1A has just one valence electrons, Group 2A has two valence electrons.........Group 8A has eight valence electrons.
Moving across groups is synonymous to moving from left to right on the periodic table.
Due to this trend, the periodic table is arranged based on the number of valence electrons.

3. explain how you know the number of valence electrons for each group.

The number of valence electrons in a group is the group number:

Group Number valence electrons

1A 1

2A 2

3A 3

4A 4

5A 5

6A 6

7A 7

8A 8

learn more:

Periodic table brainly.com/question/1971327

#learnwithBrainly

6 0

4 years ago

Which of these is not an example of a biotic part of the ecosystem? a. grass b. birds c. insects d. weather

Natasha_Volkova [10]

Weather. I'm pretty sure.

8 0

3 years ago

Read 2 more answers

Help me to balance this equations pls! C3H8 02 CO+H20 Thank you

vichka [17]

Answer:

2C3H8 402 6CO+8H20

Explanation:

8 0

3 years ago

What would be the freezing point of a solution that has a molality of 1.324 m which was prepared by dissolving biphenyl (C12H10)

lbvjy [14]

The freezing point of a 1.324 m solution, prepared by dissolving biphenyl into naphthalene, is 71.12 ° C.

A solution is prepared by dissolving biphenyl into naphthalene. We can calculate the freezing point depression (ΔT) for naphthalene using the following expression.

$\Delta T = i \times Kf \times m = 1 \times 6.90 \°C/m \times 1.324m = 9.14 \°C$

where,

i: van 't Hoff factor (1 for non-electrolytes)
Kf: cryoscopic constant
m: molality

The normal freezing point of naphthalene is 80.26 °C. The freezing point of the solution is:

$T = 80.26 \° C - 9.14 \° C = 71.12 \° C$

The freezing point of a 1.324 m solution, prepared by dissolving biphenyl into naphthalene, is 71.12 ° C.

Learn more: brainly.com/question/2292439

3 0

3 years ago

If element x forms the oxides xo and x2o3 the oxidation numbers of element x are

Deffense [45]

Answer:

b) +2 and +3.

Explanation:

Hello,

In this case, given the molecular formulas:

$XO$

And:

$X_2O_3$

We can relate the subscripts with the oxidation states by knowing that they are crossed when the compound is formed, for that reason, we notice that oxygen oxidation state should be -2 for both cases and the oxidation state of X in the first formula must be +2 since both X and O has one as their subscript as they were simplified:

$X^{+2}O^{-2}$

Moreover, for the second case the oxidation state of X should be +3 in order to obtain 3 as the subscript of oxygen:

$X_2^{+3}O_3^{-2}$

Thus, answer is b)+2 and +3

Best regards.

3 0

3 years ago