How do you determine formula units in a unit cell?

Answers

Answer 1
Answer: In order to determine the number of formula units of a substance in a cell, you need to know the density of the substance and the edge length of the unit cell. Suppose that you are given the following problem:The density of TlCl(s) is 7.00 g/cm³, and the length of an edge of a unit cell is 385 pm. How many formula units of TlCl are in a unit cell?
Here’s how you solve the problem.
Calculate the volume of the unit cell.
If the length of an edge of the cell is a, then V = a³.
V = (385 × 10⁻¹² m)³ = 5.71 × 10⁻²⁹ m³Use the density to calculate the mass of the unit cell (The density of TlCl is the same, no matter what volume of TlCl we have).
Mass = 5.71 × 10⁻²⁹ m³ × (7.00 g/1 cm³) × (100 cm/1 m)³ = 3.99 × 10⁻²² gUse the molar mass to convert grams to moles.
3.99 × 10⁻²² g × (1 mol/239.8 g) = 1.67 × 10 ⁻²⁴ molUse Avogadro’s number to calculate the number of formula units.
1.67 × 10 ⁻²⁴ mol × (6.022 × 10²³ formula units/1 mol) = 1.00 formula units
Therefore, 1 unit cell of TlCl contains 1 formula unit.
Answer 2
Answer:

Final answer:

To determine the formula units in a unit cell, understand the type of the unit cell structure (simple cubic, body-centred cubic, or face-centred cubic) and apply the appropriate calculation for that type.

Explanation:

To determine the number of formula units in a unit cell, one must first understand what these terms mean. A unit cell is the smallest repeating unit of a crystal lattice. There exist several different types that affect formula unit arrangement and quantity, including simple cubic, body-centred cubic, and face-centred cubic.

A crystal lattice is a three-dimensional framework of atoms, ions, or molecules arranged in a repeating pattern. The formula unit is the lowest whole-number ratio of ions represented in an ionic compound. In a simple cubic unit cell, there's one formula unit, in a body-centred cubic cell, there are two, and in a face-centred cubic cell, there are four.

For instance, if you are dealing with a simple cubic arrangement the unit cell is composed of 8 atoms forming the vertices and each one is shared amongst 8 neighbouring cells, you have (8 x 1/8 = 1) formula unit per cell. Similarly, in a body-centred cubic, there is 1 atom in the centre fully inside, and 8 on the corners shared with neighbouring cells, hence (1 + 8 x 1/8 = 2) formula units per unit cell.

Learn more about Unit Cells and Formula Units here:

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Air pollution from automobiles and industrial power plants can be a source of chemical weathering due to the formation ofA. soil.
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Answers

Also acid rain is created from the pollution of automobiles
Air pollution from automobiles and industrial power plants can be a source of chemical weathering due to the formation of   C. iron oxides.

In your own words, compare and contrast transverse and longitudinal waves. Be sure to include at least one similarity and one difference.

Answers

A transversewave is a wave is a wave in which the particles in the medium oscillate in a direction that is perpendicular or at 90 degrees to the direction in which the wave propagates. Light waves or electromagnetic waves are a good example of transverse waves. When an electromagnetic wave propagates, the medium in which it propagates vibrates in a direction perpendicular to the direction of travel.

A longitudinal wave is a wave in which the particles of the medium oscillate in a direction parallel to the direction in which the wave is travelling.  Sound waves are good examples of longitudinal waves. When sound propagates, the particles of the medium which it travels through will vibrate in the direction in which the wave is travelling.

                                         Similarities

  • Both transverse and longitudinal waves carry energy.
  • Both transverse and longitudinal waves obey the wave equation.
  • Both transverse and longitudinal waves show behavior such as refraction, reflection, absorption, diffraction, etc.

                                          Differences

The main difference is that for longitudinal waves, the particles in the medium will vibrate in the direction of the wave and that for transverse waves, the motion of the particles in the medium is in a direction perpendicular to the direction of propagation of the wave.

Which of the following would be the best name for MgCl2? magnesium chlorine magnesium chloride magnesium dichloride monomagnesium dichloride

Answers

Answer:  magnesium chloride

Explanation: Magnesium chloride is an ionic compound which is formed by combination of Mg^(2+) and Cl^- ions.

The name of the ionic compound is written as follows:

The name of the metal is written first followed by the name of the non metal without any prefix but the name of the non metal ends with ide, ite, ate or ite.

Thus the name of MgCl_2 is magnesium chloride.


It would be magnesium chloride.

Chlorine is a wrong name for Cl.

Dichloride doesn't work, even though Cl2 is 2 chloride, but according to some laws of nomenclature, saying dichloride isn't necessary so we don't say it.

And monomagnesium isn't right for the same reason as above.

WORTH 40 POINTSOK so I’m doing a science fair project and I need a title for it. The project is on amount of protein in milk. The question is what type of cows milk has the highest amount of protein.

(Also I asked once before, someone just said MOO! can you add onto that for the title?)

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Answer:

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Explanation:

Answer:

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A fruit and oatmeal bar contains 142 nutritional calories. Convert this energy to calories

Answers

Answer is: a fruit and oatmeal bar contains 142000 calories.
A nutritional calorie, or kilocalorie, is equal to 1000 calories.
E = 142 kcal · 1000 cal/kcal.
E = 142 000 cal.
Calorie (cal), or small calorie, is the amount of energy needed to heat one gram of water by one degree Celsius.
One small calorie is approximately 4.2 joules.
A calorie is a unit of energy.

Final answer:

142 nutritional calories (Cal) are equal to 142,000 calories (cal) since one nutritional Calorie is equivalent to 1000 scientific calories (cal).

Explanation:

To convert 142 nutritional calories to calories, you need to understand the relationship between the two units. In nutrition, when we say 'calories', we actually mean 'kilocalories' (kcal). One nutritional calorie (with an uppercase C) is equal to one kilocalorie (kcal), and one kilocalorie is equivalent to 1000 calories (with lowercase c).

Therefore, 142 nutritional calories (Cal) are equivalent to 142,000 calories (cal).

The conversion formula is as follows:
142 Cal * 1000 = 142,000 cal

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Answers

Answer:

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Explanation:

the answer is liters after searching and searching and searching i found it now i winnnn

Answer:

LITERS (B)

Explanation: