Consider the following: Li(s) + ½ I₂(g) --> LiI(s) ΔH = –292 kJ. LiI(s) has a lattice energy of –753 kJ/mol. The ionization energy of Li(g) is 520 kJ/mol, the bond energy of I₂(g) is 151 kJ/mol, and the electron affinity of I(g) is –295 kJ/mol. Use these data to determine the heat of sublimation of Li(s).

Answers

Answer 1

Answer:

Heat of sublimation of Li(s) = 160.5 kJ/mol

Explanation:

Given that:

[tex]\mathtt{2Li(s) + \dfrac{1}{2} I_2(g) \to 2LiI(s)}[/tex]

ΔH = –292 kJ

The heat of formation for the above reaction =  –292 kJ × 2 =  -584 kJ/mol

[tex]\mathtt{Li^+_{(g)} + I^-_{(g)} \to LiI_{(s)}}[/tex]

The lattice energy of LiI(s) = -753 kJ/mol

[tex]\mathtt{Li(g)\to Li^+(g) + e^- }[/tex]

The ionization energy of LiI(s) = +520 kJ/mol

[tex]\mathtt{I_2_{(g)} \to 2I_{(g)} }[/tex]

The Bond Energy of I₂(g) = 151 kJ/mol

[tex]\mathtt{I_{(g)} + e^- \to I^-_{(g)}}[/tex]

The electron affinity of I(g) = -295 kJ/mol

Heat of sublimation: Sublimation is the process of changing of a solid matter into gas without passing through the liquid stage, Now, the molar heat of sublimation is the amount of energy that must be added to a mole of solid  to turn it directly into a gas without any interference through the liquid phase provided the pressure is  constant.

From  the above reactions: The heat of sublimation  of Li(s) can be calculated by the sum total of the following.

[tex]\mathtt{Li_{(s)} + \dfrac{1}{2} I_2_{(g)} \to LiI_{(s)} \ \ -292 kJ/mol} \\ \\\mathtt{I_{(g)} \to \dfrac{1}{2} I2(g) \ \ -75.5 kJ/mol} \\ \\ \mathtt{I^-(g) \to I(g) + e^- \ \ +295 kJ/mol} \\ \\ \mathtt{LiI(s) \to Li^+_{(g)} + I^-_{(g)} \ \ +753 kJ/mol} \\ \\ \mathtt{Li^+_{(g)} + e^- \to Li(s) \ \ -520 kJ/mol} \\ \\[/tex]

[tex]\mathtt{Li(s) \to Li(g)}[/tex] = (-292 +(-75.5)+295+753+(-520)) kJ/mol

[tex]\mathtt{Li(s) \to Li(g)}[/tex] =  160.5 kJ/mol

Heat of sublimation of Li(s) = 160.5 kJ/mol


Related Questions

When two ionic compounds are dissolved in water, a double replacement reaction can... Group of answer choices occur if two of the ions form an insoluble ionic compound, which precipitates out of solution occur if the ions react to form a gas, which bubbles out of the solution never occur since all ions are in water occur if the ions react to form a gas, which bubbles out of the solution ionic compounds only react with nonmetals

Answers

Answer:

occur if two of the ions form an insoluble ionic compound, which precipitates out of solution

Explanation:

When two ionic compounds are dissolved in water, a double replacement reaction takes place if two of the ions form an insoluble ionic compound, which precipitates out of solution. In double displacement reaction ions switch partners. And hence, produce an insoluble precipitate.

compare the activity of sodium and iron with water and dilute acid​

Answers

Answer:

Reactions of sodium with water and dilute acid

Sodium reacts explosively with dilute HCl(aq) to produce NaCl(aq) and H₂(g)

2Na (s) + 2HCl(aq) → 2NaCl(aq) + H₂(g)

Sodium reacts violently with cold water to produce NaOH(aq) and H₂(g)

2Na (s) + H₂O(l)  → 2Na(OH)(aq) + H₂(g)

The produced hydrogen may become ignited and explode

Reactions of iron with water and dilute acid

Iron reacts very slowly with dilute acid to produce iron (II) chloride and hydrogen gas

Fe (s) + 2 HCl (aq) →  FeCl₂ (aq) + H₂ (g)

Iron does not react with cold water. Iron reacts only with steam

Explanation:

What is the equilibrium constant of aA+bB cC +dD?

Answers

Explanation:

{c}^C . {d}^D / {a}^A . {b}^B

calculate the weight of 3.491 into 10 to the power 19 molecules of cl2​

Answers

Answer:

The mass of 3.491 × 10¹⁹ molecules of Cl₂  of Cl₂ is 4.11 × 10⁻³ grams

Explanation:

The number of particles in one mole of a substance id=s given by the Avogadro's number which is approximately 6.023 × 10²³ particles

Therefore, we have;

One mole of Cl₂ gas, which is a compound, contains 6.023 × 10²³ individual molecules of Cl₂

3.491 × 10¹⁹ molecules of Cl₂ is equivalent to (3.491 × 10¹⁹)/(6.023 × 10²³) = 5.796 × 10⁻⁵ moles of Cl₂

The mass of one mole of Cl₂ = 70.906 g/mol

The mass of 5.796 × 10⁻⁵ moles of Cl₂ = 70.906 × 5.796 × 10^(-5) = 4.11 × 10⁻³ grams

Therefore;

The mass of 3.491 × 10¹⁹ molecules of Cl₂  of Cl₂ = 4.11 × 10⁻³ grams.

Consider the hypothetical chemical reaction represented by the equation 3 A + 2 B → A 3B 2 Which of the following is a correct interpretation of this equation? i. 3 grams of A react with 2 grams of B to form 1 gram of A 3B 2 ii. 3 atoms of A react with 2 atoms of B to form 1 molecule of A 3B 2 iii. 3 moles of A react with 2 moles of B to form 1 mole of A 3B 2

Answers

Answer:

iii. 3 moles of A react with 2 moles of B to form 1 mole of A 3B 2

Explanation:

A + 2 B → A 3B 2

A chemical equation among other things, gives the stoichiometry of the reaction; that is the relationship between reactants and products.

This relationship is basically stated in moles form the coefficients of the reactants and product.

From the reaction above, we can say;

1 mol of A reacts with 2 mol of B to form 1 mol of A3B2

It cannot be grams because the reactants and products all have different molar masses.

The correct interpretation of the equation of the hypothetical chemical reaction is; Choice (iii) 3 moles of A react with 2 moles of B to form 1 mole of A 3B 2.

Definition:

Chemical equations are equations that make use of chemical formulae and symbols to represent chemical reactions. The left-hand side of a chemical equation represents the reactants and the right-hand side represents the products.

Each reacting entity is also assigned its corresponding stoichiometric coefficient.

However, this stoichiometric coefficient is to quantify the no. of moles of the reactants consumed or products formed as the case may be.

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Over the period of a few days, a hospital receives an overwhelming increase in the number of patients with food poisoning. How would a scientist respond to this increase in sick patients?

Answers

Answer:

Hey there!

A scientist would try to determine the cause of the food poisoning, and see if the people who got poisoned had anything in common, for example: they ate at the same restaurant, they are all people of a certain age, etc.

Let me know if this helps :)

When an object falls toward the ground due to gravity, what type of energy becomes kinetic energy?

Answers

Answer:

potential energy (gravitational)

Explanation:

Potential energy is the energy that is stored in an object due to its position relative to some zero position. An object possesses gravitational potential energy if it is positioned at a height above (or below) the zero height. If we think of the ground as the zero height, the height of the object is coming down from a positive height.  Wherever it is relative to the zero height, it is stored at that height, meaning that it is potential energy at that particular height.  When it moves to the ground, it becomes kinetic, by gravitational means.

Answer:

Potential

Explanation:

0.32 L is equal to how many mL

Answers

Its 320 milliliters.

3. What amount of
space is taken up by a rock that weighs 150 milligrams, and
has a density of 30 mg/ml? (Express your answer in Liters)

Answers

Hey there!:

Density = 30 mg/mL

Mass = 150 mg

Volume = ??

Therefore:

D = m / V

30 = 150 / V

V = 150 / 30

V = 5.0 mL

converts volume into liters :

5.0 mL / 1000 => 0.005 L or 5.0 x 10⁻³ L

Hope this helps!

Find the density of a cube on Earth that weighs 1.5 kg and has a side-length of 10 cm.

Answers

Answer:

1.5g/cm³

Explanation:

density=mass÷volume

mass= 1.5kg (change into g) = 1500g

volume of the cube = 10×10×10 = 1000cm³

density= divide 1500g÷1000cm = 1.5g/cm³

Density= 1.5g/cm³

YOUR WELCOME!

The density of the cube on Earth that weighs 1.5 kg and has a side length of 10 cm is 1.5g/cm³

What is density?

"Density is the mass per unit volume. Density is a scalar quantity. It is denoted by d and the symbol for density is given as rho, a Greek symbol. Density is calculated as mass divided by volume."

density = mass / volume

The mass of the cube on earth is 1.5 kg

The side length of the cube is 10 cm.

The mass is given in kg. It is converted into grams.

mass= 1.5kg (change into g) = 1500g

A cube is a three-dimensional square, it has 6 faces, so its volume will be calculated completely.

Volume of the cube = 10×10×10 = 1000cm³

Putting the values in the formula of density

density= divide 1500g /1000cm = 1.5g/cm³

Thus, the density of the cube on Earth is 1.5g/cm³.

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If two solutions with concentrations of 0.4 M sugar and 0.7 M sugar respectively are separated by a semipermeable membrane, during osmosis there is a net flow of Group of answer choices sugar molecules from the dilute to the concentrated solution sugar molecules from the concentrated to the dilute solution water molecules from the concentrated to the dilute solution water molecules from the dilute to the concentrated solution

Answers

Answer: Water molecules from the dilute to the concentrated solution

Explanation:

During Osmosis if a solution is separerated by a semipermeable membrane, the solvent (typically water) from the less concentrated solution in terms of solute goes through the semipermeable membrane to the solution with the higher concentration so that the concentrations between the solutions can be balanced.

With the above solutions therefore, water molecules would move from the solution of 0.4M of sugar to the solution with a 0.7M of sugar through the semipermeable membrane.

During osmosis, water molecules move from the dilute to the concentrated solution.

OSMOSIS:

Osmosis is the movement of water molecules from a region of higher concentration (low concentration of solute) to a region of lower concentration (higher concentration of solute).

The principle of movement is based on the concentration gradient i.e. difference in concentration across a semipermeable membrane.

According to this question, two solutions have sugar concentrations of 0.4 M sugar and 0.7 M respectively and are separated by a semipermeable membrane.

Therefore, water molecules will move from the dilute (0.4M) to the concentrated (0.7M) solution during osmosis.

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Examine the given reaction. NH4NO3(s) → NH4+(aq) + NO3–(aq) ΔH° = 25.45 kJ/mol ΔS° = 108.7 J/mol·K Which of the given is correct about the ΔG° at 25 °C?
A)+4,360 J
B)−6,942 J
C)−4,360 J
D)+6,942 J

Answers

Answer:

B)−6,942 J /mol

Explanation:

At constant temperature and pressure, you cand define the change in Gibbs free energy, ΔG, as:

ΔG = ΔH - TΔS

Where ΔH is enthalpy, T absolute temperature and ΔS change in entropy.

Replacing (25°C = 273 + 25 = 298K; 25.45kJ/mol = 25450J/mol):

ΔG = ΔH - TΔS

ΔG = 25450J/mol - 298K×108.7J/molK

ΔG = -6942.6J/mol

Right solution is:

B)−6,942 J /mol

What is the main factor responsible for the acidic and basic character of oxides?
Explain your answer.​

Answers

Explanation:

We define non-metal oxide acidity in terms of the acidic solutions formed in reactions with water. For example, sulfur trioxide reacts with water to forms sulfuric acid. In sum, acidic oxides are oxides of non-metals, and basic oxides are oxides of metals. ... CrO is basic, Cr2O3 is amphoteric and CrO3 is acidic.

Reply me in comments

Please help, this assignment is to hard for me. :(

Answers

Answer:

603000 J

Explanation:

The following data were obtained from the question:

Energy required (Q) =...?

Mass (M) = 10000 g

Specific heat capacity (C) = 2.01 J/g°C

Overheating temperature (T2) = 121°C

Working temperature (T1) = 91°C

Change in temperature (ΔT) =.?

Change in temperature (ΔT) =T2 – T1

Change in temperature (ΔT) = 121 – 91

Change in temperature (ΔT) = 30°C

Finally, we shall determine the energe required to overheat the car as follow:

Q = MCΔT

Q = 10000 × 2.01 × 30

Q = 603000 J

Therefore, 603000 J of energy is required to overheat the car.

Which of these scientist is know for his work in understanding climate change a : edwin hubble b : christian doppler c : warren washington d : charles kuen kao

Answers

Answer: just trust me its c

Explanation: i dont cap

What are the requirements of any hypothesis in science?

Answers

Answer:

A scientific hypothesis must meet 2 requirements:

Explanation:

A scientific hypothesis must be testable, and;

A scientific hypothesis must be falsifiable.

What is the term for the belief that one's own culture is superior to other
cultures?
O A. Cultural behavior
O B. Cultural competence
C. Cultural relativism
D. Cultural absolutism

Answers

The belief that one's own culture is superior to others would be D - Cultural Absolutism. It
declares a society's culture to be of supreme ethical value to other cultures.

Hope this helps!

Cultural absolutism is the term for the belief that one's own culture is superior to other cultures.

What is cultural absolutism?

Cultural absolutism is one of the perspectives which is common in anthropology, but it can  also be applied to non-scientific thoughts also. It assumes that there is a set of universal values which are objectively valid in every  situation.

Today, pure cultural absolutism is seen as a harmful effect of ethnocentrism focusing on  the belief that one's own culture is superior and the practice of holding other's cultures to the standard of our own. However, purely relativist anthropologists have also been critiqued for going too far, by  denying any common humanity and being too lenient towards morally questionable practices. Contemporary approaches try to find a balance between  the universal values, such as human dignity, and a more inclusive and relativistic side  of culture.

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WILL GIVE A BRAINLIEST FOR THE ANSWER.
Pls open the picture for the question. I need the answer ASAP.​

Answers

Answer:

(i) There is a very fast rate at t1, as its slope is the most significant, at t2 the rate is still positive, but it has decreased compared to t1, and at t3 the rate is almost constant, as seen by the nearly flat slope.

(ii) The trend in the reaction rate is logarithmic, with a very fast reaction rate at the beginning that slowly decreases.

Explanation:

What is the outcome of all chemical changes when two substances are combined?​

Answers

Answer:

This is called a chemical reaction. gas may form.heat may be produced and the color may change

Balance the reaction which forms ions. Choose "blank" if no coefficient other than 1 is needed. ZnBr2 what Zn + + what Br-


1 or 2 or black

Answers

Answer: [tex]ZnBr_2\rightarrow Zn^{2+}+2Br^-[/tex]

Explanation:

For formation of a neutral ionic compound, the charges on cation and anion must be balanced. The cation is formed by loss of electrons by metals and anions are formed by gain of electrons by non metals.  

Here zinc is having an oxidation state of +2 called as  [tex]Zn^{2+}[/tex] cation and bromide is an anion with oxidation state of -1. Thus 2 atoms of [tex]Br^-[/tex] will combine with one [tex]Zn^{2+}[/tex] and written in simplest whole number ratios to give neutral [tex]ZnBr_2[/tex]

[tex]ZnBr_2\rightarrow Zn^{2+}+2Br^-[/tex]

If you have a little air in a balloon, find the volume of the balloon if the mass is 0.6 g and the density of the air is 0.0012 g / mL

Answers

Hey there!:

Mass = 0.6 g

Density = 0.0012 g/mL

Volume = ??

Therefore :

Density = mass / Volume

0.0012 = 0.6 / V

V = 0.6 / 0.012

V = 500 mL

Hope this helps!

9.7300x10^2
+
9.8700x10^3

[?]x10^[?]​

Answers

Answer:

1.0843×10^4

Explanation:

If we are to add 9.7300x10^2 + 9.8700x10^3, we must first make the powers of the both to be be the same so that we can carry out any mathematical manipulation of interest. So we can have;

9.7300x10^2 + 98.700x10^2

When we now add the both we have (9.7300 + 98.700)×10^2.

This now gives us the result, 108.43×10^2 which is correctly written as 1.0843×10^4, according to the rules of writing in scientific notation.

ANSWER ASAP WILL GIFT BRANILIEST Which of the following happens to a molecule of an object when the object is cooled? A Its temperature increases. B It loses kinetic energy. C Its size increases. D It moves faster.

Answers

Answer:

It loses kinetic energy.

Explanation:

The definition of heat is molecules moving fast, so it cooling would mean they slow down.

Answer:

B, It loses kinetic energy.

Explanation:

PLZ HELP! TIMED TEST Which of the following groups of elements are likely to have elements in the three states of matter? (1 point)
Alkali metals
Actinides
Halogens
Lanthanides

Answers

Answer:

Halogens

Explanation:

Matter is defined as a substance which has mass and occupies volume. The three states of matter are solid, liquid and gas.

Elements which are present in group 17 are known as halogens.

Elements present in this group are fluorine, chlorine, bromine and iodine.

At room temperature, both fluorine and chlorine exists as a gas.

Bromine exists as a liquid and iodine exists as a solid.

Therefore, we can conclude that halogen groups are likely to have elements in three states of matter.

why there are two chloride ions for every calcium ion

Answers

Answer:

The valency of calcium is +2

Explanation:

Calcium is in group two. The members of group two are divalent metals that loose two electrons to form M^2+.

Since they form M^2+, they form ionic bonds with two uninegative ions. Chlorine is in group 17. This implies that its valency is -1 and it accepts one electron when it participates in an ionic bond.

Hence it will take two chlorine atoms to receive two electrons from one calcium atom in an ionic bond making the ratio of calcium to chlorine in the compound 2:1.

CO2(g) + H2(g)
cog) + H2O(1)
What is being oxidized?
carbon
O carbon dioxide
oxygen
hydrogen

Answers

Answer:

Hydrogen

Explanation:

This may be wrong but I can't really tell because of how you have written the question

Answer: The answer is D. Hydrogen

Explanation:

I took the test

The pH of a solution decreases by 2.0. How does the hydronium ion concentration of the solution change? Increases to 2 times the original concentration increases to 100 times the original concentration decreases to one one hundredth. Of the original concentration decreases to one half. Of the original concentration

Answers

Answer:

The hydronium ion concentration increases to 100 times the original concentration

Explanation:

The pH of a solution is defined as the negative logarithm of the hydrogen or hydronium ion concentration of that solution. It is given by the expression below:

pH = -log[H₃O⁺] = log[H₃O⁺]⁻¹

Assuming the solution was at neutral with original pH = 7;

The new pH of the solution will be = 7 - 2 = 5

At pH = 7;

log[H₃O⁺]⁻¹ = 7

[H₃O⁺]⁻¹ = 10⁷

[H₃O⁺] = 10⁻⁷

At pH = 5

log[H₃O⁺]⁻¹ = 5

[H₃O⁺]⁻¹ = 10⁵

[H₃O⁺] = 10⁻⁵

10⁻⁵ = 10⁻⁷ * 10²

But 10² = 100

Therefore, the hydronium ion concentration increases to 100 times the original concentration

Answer:

B

Explanation:

On Edge

In the laboratory, a volume of 100 mL of sulfuric acid (H2SO4) is recorded. How many g are there of the liquid if its density is 1.83 g / cm3?

Answers

Answer:

[tex]\large \boxed{\text{183 g}}[/tex]  

Explanation:

[tex]\begin{array}{rcl}\text{Density} & = & \dfrac{\text{Mass}}{\text{Volume}}\\\\\rho & = &\dfrac{m}{V}\\\\1.83 \text{ g$\cdot$ cm}^{-3} & = & \dfrac{m}{\text{100 cm}^{3}}\\\\m & = & \text{183 g}\\\end{array}\\\text{There are $\large \boxed{\textbf{183 g}}$ of sulfuric acid.}[/tex]

which one of the following has the smallest atomic radius a)Mg2+ b)O2- c)Na+ d)F-

Answers

Answer:

Mg2+

Explanation:

o2- =2,8

mg2+ =2,8

na+ =2,8

f- =2,8

since they are all same it depends on protons.

mg2+ has least protons

take an onion and one jam bottle insert the roots of onion in the jam bottle for five days . after five days observe the growth in the roots of onion which is submerged in jam bottle. write observation here

Answers

Answer:

It is noticed that after five days, there is elongation of the root cells in the roots of onion in the jam bottle

Explanation:

It is noticed that after five days, there is elongation of the root cells in the roots of onion in the jam bottle. The growth of a plant is due to the availability of the growing and  dividing cells in the meristematic regions of the apical meristems. (stem cells). This site are active site for elongation and differentiation  of the stem tissues. In the apical meristem of the root cells, the cells have the potential to carry out mitosis and cell division repeatedly in order to generate newer cells for extension and development of stems and leaves. With each cell division, one cell remains in the meristem which the other increases in size and differentiate due to different genomic expression to form the meristem regions which eventually becomes the stem structure.

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