35 POINTS -- REAL ANSWERS (please)



For each of your three trials state the following:



⢠heat needed to melt the ice (q) (I got 18* for all)


⢠enthalpy of fusion (I'm not sure how to find the mass of the ice melted)


⢠percent error from the accepted enthalpy of fusion of water of 334 J/g (I don't understand this, we never went over this)

Answer:

For 25.6 grams of oxygen you will need 2*25.6 grams of hydrogen because water has two molecules of hydrogen and one molecule of oxygen the final mass of water is 76.8 grams

The dissolving of sodium hydroxide is an endothermic process.

The given thermochemical equation shows that the dissolution of NaOH is an endothermic process. The negative value of the enthalpy change (AH) indicates that energy in the form of heat is absorbed during the process of dissolving NaOH. This means that the system requires energy to break the ionic bonds between NaOH molecules and to separate them into their constituent ions, Na+ and OH-. Option A is incorrect as potential energy is not mentioned in the equation, and option D is not related to the given equation. Option C is not necessarily true, as the temperature change of the solution depends on the amount of NaOH dissolved and the specific heat of the solution. Overall, we can conclude that the dissolution of NaOH is an endothermic process, where heat is absorbed by the system, and the enthalpy of the system increases.

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The molality of the solution is 2.57 mol/kg.

We need to determine the number of moles of solute (in this case, KOH) dissolved in a specified mass of the solvent (in this case, water).

First, let's convert the given mass of KOH to moles:

molar mass of KOH = 56.11 g/mol

moles of KOH = mass of KOH / molar mass of KOH

moles of KOH = 85 g / 56.11 g/mol

moles of KOH = 1.515 mol

Next, we need to calculate the mass of the solvent (water) in kilograms:

mass of solvent = 590. g

mass of solvent in kg = mass of solvent / 1000

mass of solvent in kg = 590. g / 1000

mass of solvent in kg = 0.590 kg

Now we can use these values to calculate the molality of the solution:

molality = moles of solute / mass of solvent in kg

molality = 1.515 mol / 0.590 kg

molality = 2.57 mol/kg

Therefore, the molality of the solution is 2.57 mol/kg.

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When ethanedioic acid (HOOC-COOH) reacts with two 1,2-ethanediol molecules (HOCH₂CH₂OH), it forms a trimmer polymer.

Polymer is a material composed of long chain molecules, or macromolecules, which are made up of many repeating smaller units, known as monomers. Polymer molecules can be natural, such as cellulose, or synthetic, such as plastics and rubbers. Polymers are used to produce a wide range of materials with different characteristics and properties.

The HOOC group of the ethanedioic acid molecule reacts with the two hydroxyl groups of the two 1,2-ethanediol molecules to form the ester linkages. This produces a trimmer polymer, with three monomers connected via two ester linkages.

O

 |

HOOC-COO-O-CH₂CH₂-O-CH₂CH₂-OH

 |

 O

 H

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The concentration of the [tex]CH3NH2[/tex] solution is 1.84 M.

The balanced equation for the reaction between [tex]HCl[/tex]and [tex]CH3NH2[/tex] is:

[tex]CH3NH2 + HCl → CH3NH3+Cl-[/tex]

From the equation, we can see that the acid and base react in a 1:1 molar ratio. Therefore, we can use the following equation to calculate the concentration of the [tex]CH3NH2[/tex]solution:

[tex]M(CH3NH2) x V(CH3NH2) = M(HCl) x V(HCl)[/tex]

where:

[tex]M(CH3NH2)[/tex]= concentration of [tex]CH3NH2[/tex] solution (unknown)

[tex]V(CH3NH2)[/tex] = volume of [tex]CH3NH2[/tex] solution used (unknown)

[tex]M(HCl)[/tex] = concentration of[tex]HCl[/tex]solution (1.84 M)

[tex]V(HCl)[/tex] = volume of [tex]HCl[/tex] solution used (28.25 mL or 0.02825 L)

Solving for [tex]M(CH3NH2)[/tex], we get:

[tex]M(CH3NH2) = (M(HCl) x V(HCl)) / V(CH3NH2)[/tex]

[tex]M(CH3NH2)[/tex] = (1.84 M x 0.02825 L) / 0.02825 L

[tex]M(CH3NH2)[/tex] = 1.84 M

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The difference in the rate of sugar and acid reaction compared to the reaction between KI(aq) and Pb(NO₃)₂(aq) is due to the type of chemical bonding involved.

The reaction between sugar and acid involves covalent bonding, which is a strong bond that requires significant energy input to break. This type of bonding is responsible for the slow rate of the sugar and acid reaction.

In contrast, the reaction between KI(aq) and Pb(NO₃)₂(aq) involves ionic bonding, which is a much weaker bond than covalent bonding. As a result, the ions in the reactants are more easily separated, leading to a faster reaction rate.

Ionic bonding involves the transfer of electrons from one atom to another, whereas covalent bonding involves the sharing of electrons between atoms. This difference in electron sharing or transfer contributes to the different reaction rates observed between covalent and ionic bond containing compounds.

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When a wave passes through water, the particles of water move in a circular motion, which is often described as an orbital motion.

The circular motion of water particles is created by the energy of the wave, which causes the water to oscillate up and down or back and forth in the same place.

As the wave moves through the water, the energy is transferred from particle to particle in a circular motion, causing the water to move in a wave pattern that travels outward from its source. This circular motion is why water waves do not carry water particles along with them, but rather simply transfer energy through the water.

This motion is also what creates the phenomena of waves breaking on shorelines, as the circular motion of water particles becomes disrupted by the shallow water and causes the wave to collapse.

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The transition within an atom that is not possible is an electron begins in an excited state and then gains enough energy to become ionized. Option D is correct.

An excited electron already has excess energy above its ground state energy level. If it gains more energy, it can transition to a higher energy level or even become ionized by being ejected from the atom. However, an electron that has already been excited and has reached its highest energy level cannot gain any more energy from the atom and therefore cannot be ionized further.

Once an electron is in its highest energy level, it is said to be in the ionization continuum and cannot be further excited or ionized by the atom. Therefore, the transition of an electron beginning in an excited state and then gaining enough energy to become ionized is not possible. On the other hand, the other three transitions listed are possible and occur naturally in many physical and chemical processes, such as atomic emission and absorption spectra. Option D is correct.

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Answer: 1.20x10^24 atoms O

Explanation:

Oxygen is a diatomic element and is O2

Each molecule of oxygen, O2, has 2 atoms of O.

Each mole has 6.022 x 10^23 molecules of O2.

So our equation is

(6.022x10^23) x 2 = 1.2044x10^24 atoms of O2.

and because our initial problem uses 3 sig figs we round that to

1.20 x 10^24 atoms of O.

The sentence that shows humans' main problem is "The level of carbon dioxide in Earth's atmosphere has risen consistently for decades, trapping extra heat near the surface of the Earth," which is the last option.

The sentence that shows humans' main problem is "The level of carbon dioxide in Earth's atmosphere has risen consistently for decades, trapping extra heat near the surface of the Earth." This sentence indicates that the main problem is the increasing levels of carbon dioxide in the Earth's atmosphere caused by human activities. This increase in carbon dioxide is resulting in global warming, where heat is being trapped near the Earth's surface, leading to several negative effects, including rising sea levels, changes in weather patterns, and loss of biodiversity.

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The name of this branched alkene is 6- ethyl-8-methyl-5-propylnon-2-ene.

The longest carbon chain containing the carbon-carbon double bond is selected as the parent alkene.

The suffix ‘ane’ of the alkane is replaced by ‘ene’.

The position of double bonds or side chains indicated by numbers 1, 2, 3 etc.

The longest chain is numbered from that end, which gives the lowest number to the carbon atom of the double bond and written just before the suffix ‘ene’. If while numbering the chain the double bond gets the same number from either side the carbon chain is numbered in such a manner that the substituent gets the lowest number.

The name and position of other groups (substituents) is indicated by prefixes.

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C. No Reaction will be the products when CuF2 reacts with Li

The positive and negative ions of two ionic compounds switch positions to generate two new compounds in a process known as a double replacement reaction. In aqueous solution, double-replacement reactions often take place between compounds.

In conclusion, you cannot balance a reaction by modifying or adding new components. To ensure that mass is preserved, the only thing you can do is alter the quantity of particles, or moles of particles, involved.

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To answer this question, we need to use the ideal gas law, which is PV = nRT, where P is the pressure, V is the volume, n is the number of moles of gas, R is the ideal gas constant, and T is the temperature. We also need to use the concept of molar volume, which is the volume occupied by one mole of a gas at a specific temperature and pressure.

First, we need to find the number of moles of gas that occupies 350.0L at standard pressure (1 atm) and temperature (273 K). This can be calculated using the formula n = PV/RT, where P = 1 atm, V = 350.0L, R = 0.08206 L atm/mol K, and T = 273 K. Substituting these values, we get n = (1 atm x 350.0L)/(0.08206 L atm/mol K x 273 K) = 14.15 mol.

Next, we need to find the molar volume of the gas at the pressure and volume we want it to occupy. Using the same formula, but with the new pressure (P') and volume (V') values, we get V' = nRT/P'. Since we want the gas to occupy 3.00L, we have V' = 3.00L. We also know that the number of moles (n) and temperature (T) are constant, so we can rearrange the formula to solve for the new pressure (P'). Thus, P' = nRT/V' = (14.15 mol x 0.08206 L atm/mol K x 273 K)/3.00L = 2,062.58 atm.

Therefore, the gas must be compressed to a pressure of 2,062.58 atm in order to occupy a volume of 3.00L, assuming constant temperature and number of moles. This is a very high pressure, and it highlights the importance of understanding the properties of gases and how they behave under different conditions.

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258.72 grams of CaBr2 is consumed when 96 g of Ca(OH)2 is produced in the given reaction.

Molar mass is the mass of one mole of a substance, expressed in grams per mole (g/mol).

CaBr2 + 2KOH → Ca(OH)2 + 2KBr

From the equation, we can see that 1 mole of CaBr2 reacts with 2 moles of KOH to produce 1 mole of Ca(OH)2 and 2 moles of KBr.

We need to first determine the number of moles of Ca(OH)2 produced from 96 g of Ca(OH)2. The molar mass of Ca(OH)2 is:

Ca(OH)2 = 1 x 40.08 (molar mass of Ca) + 2 x 16.00 (molar mass of O) + 2 x 1.01 (molar mass of H)

= 74.10 g/mol

Number of moles of Ca(OH)2 produced = Mass of Ca(OH)2 / Molar mass of Ca(OH)2

= 96 g / 74.10 g/mol

= 1.295 moles

From the balanced equation, we know that 1 mole of CaBr2 reacts with 1 mole of Ca(OH)2. Therefore, the number of moles of CaBr2 consumed in the reaction is also 1.295 moles.

Now, we can calculate the mass of CaBr2 consumed using its molar mass. The molar mass of CaBr2 is:

CaBr2 = 1 x 40.08 (molar mass of Ca) + 2 x 79.90 (molar mass of Br)

= 199.88 g/mol

Mass of CaBr2 consumed = Number of moles of CaBr2 consumed x Molar mass of CaBr2

= 1.295 moles x 199.88 g/mol

= 258.72 g

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In the equation 2h2 + o2 + 2h2o, the two hydrogen molecules (H2) react with one oxygen molecule (O2) to form two molecules of water (H2O). This reaction is known as combustion and it requires a certain ratio of hydrogen to oxygen in order for the reaction to take place.

Here correct answer is D)

In this equation, the ratio of hydrogen to oxygen is 2:1. This means that for every one liter of hydrogen, two liters of oxygen are needed in order for the reaction to take place.

In answer to the questions, a) one liter of hydrogen would react with two liters of oxygen, b) one liter of hydrogen would react with 22.4 liters of oxygen, c) 22.4 liters of hydrogen would react with one liter of oxygen, and d) two liters of hydrogen would react with one liter of oxygen.

This equation is a great example of the law of conservation of mass, as the total number of atoms on each side of the equation remain the same

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To determine whether the current shape of the Red Sea is a result of seafloor spreading or ocean subduction, a geologist would look for evidence of faulting and volcanic activity.

If the Red Sea was formed by seafloor spreading, there would be evidence of a mid-oceanic ridge along the center of the sea. This would be characterized by a linear pattern of volcanic and seismic activity, with magnetic anomalies and a symmetrical pattern of rock age on either side of the ridge. On the other hand, if the Red Sea was formed by ocean subduction, there would be evidence of a subduction zone, characterized by a deep trench along the edge of the sea and a pattern of volcanic activity occurring inland from the trench.

Additionally, there may be evidence of compressional forces, such as folding or faulting, indicating that two tectonic plates are colliding. By analyzing these features, a geologist can determine whether the Red Sea was formed by seafloor spreading or ocean subduction.

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The pH of the resulting mixture is closest to 2.48, which is in the acidic range.

The reaction between HCl and NaOH produces water and NaCl:

HCl + NaOH → NaCl + H₂O

Moles of HCl = 1.0 mol/L × 0.5 L = 0.5 moles

Moles of NaOH = 2.0 mol/L × 0.2 L = 0.4 moles

NaOH is a limiting factor since it has fewer moles than HCl.

Excess H⁺ ions = 0.5 moles - 0.4 moles = 0.1 moles

Excess OH⁻ ions = 0.4 moles

To calculate the pH of the solution, we need to know the concentration of excess H⁺ or OH⁻ ions. Since we know the amount of excess H⁺ and OH⁻ ions, we can calculate their concentrations using the volume of the solution.

The total volume of the solution is 200 mL + 500 mL = 0.7 L

The concentration of excess H+ ions is:

[H⁺] = 0.1 moles ÷ 0.7 L = 0.143 mol/L

The concentration of excess OH- ions is:

[OH⁻] = 0.4 moles ÷ 0.7 L = 0.571 mol/L

Since the concentration of OH⁻ ions is higher than the concentration of H⁺ ions, the solution is basic. The pH can be calculated using the equation:

pH = 14 - pOH

pOH = -log[OH⁻]

pOH = -log(0.571)

pOH = 0.242

Thus, pH = 14 - 0.242 = 13.76

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233.99 g of Alz(CO₃), should precipitate out in the reaction. ​

To determine the limiting reagent in this reaction, we need to compare the number of moles of each reactant present to the stoichiometric coefficients in the balanced equation. Let's first calculate the number of moles of each reactant:
- 2 moles of AI(NO₃)₃ = 2 x 213.99 g/mol = 427.98 g
- 3 moles of Na₂CO₃ = 3 x 105.99 g/mol = 317.97 g

Next, we need to convert these masses to moles by dividing by their respective molar masses:
- Moles of AI(NO₃)₃ = 427.98 g / 213.99 g/mol = 2.00 mol
- Moles of Na₂CO₃ = 317.97 g / 105.99 g/mol = 3.00 mol

According to the balanced equation, the reaction requires 2 moles of AI(NO₃)₃ for every 3 moles of Na₂CO₃. Since we have an equal number of moles of both reactants, we can see that AI(NO₃)₃ is the limiting reagent. This means that all of the AI(NO₃)₃ will react and determine the amount of product formed.

To determine how many grams of Al₂(CO₃)₃ should precipitate out, we need to calculate the theoretical yield based on the number of moles of AI(NO₃)₃:
- 2 mol of AI(NO₃)₃produces 1 mol of Al₂(CO₃)₃
- 2.00 mol of AI(NO₃)₃ will produce 1.00 mol of Al₂(CO₃)₃

The molar mass of Al2(CO3)3 is 233.99 g/mol, so we can calculate the mass of Al₂(CO₃)₃ formed as follows:
- Mass of Al₂(CO₃)₃ = 1.00 mol x 233.99 g/mol = 233.99 g
Therefore, the theoretical yield of Al₂(CO₃)₃ is 233.99 g.

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The correct presentation is;

6 CO2 (g) + H2O (l)  → C6H12O6 (aq) + 6 O2 (g)  ΔH = 801 kJ/mole

A chemical reaction known as an endothermic reaction draws energy from its surroundings, causing the temperature of those surroundings to drop. This indicates that energy must be added to the system in order for the reaction to take place because the reactants of the reaction have a lower enthalpy (energy content) than the products.

Because the absorbed energy during an endothermic reaction is typically in the form of heat, the reaction feels cold to the touch.

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Sound is not always an indicator of an exothermic reaction. While some exothermic reactions may produce sound, others may not.

However, certain exothermic reactions that produce a lot of heat can cause nearby air molecules to rapidly expand and create pressure waves, which we hear as a sound.

For example, combustion reactions that involve burning fuels such as gasoline, natural gas, or propane can produce a loud, explosive sound as the fuel rapidly oxidizes and releases a large amount of energy in the form of heat and light.

Additionally, some exothermic reactions can cause materials to break or shatter, producing a loud cracking or popping sound. For example, the reaction between baking soda and vinegar produces carbon dioxide gas, which can cause a balloon filled with the mixture to pop with a loud sound.

So while sound alone is not conclusive evidence of an exothermic reaction, it can be a possible indicator in certain cases where the reaction produces a significant amount of heat or causes physical changes in the surrounding materials.

Other factors such as changes in temperature, light emission, or gas production may also be used as evidence to confirm an exothermic reaction.

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The new boiling point of the solution is 100°C + 0.199°C = 100.199°C.

The boiling point of a solution is dependent on the concentration of solute particles in the solvent. This can be calculated using the formula

ΔTb = Kbm

where ΔTb is the boiling point elevation, Kb is the boiling point elevation constant, and m is the molality of the solution (moles of solute per kilogram of solvent).

The molar mass of CaS is 72.14 g/mol, so we can calculate the number of moles of CaS in the solution:

35 g / 72.14 g/mol = 0.4858 mol

The molality of the solution is then:

m = 0.4858 mol ÷ 1.25 kg

m = 0.3886 mol/kg

Next, we need to find the boiling point elevation constant Kb for water. Kb for water is 0.512 °C/m.

Finally, we can calculate the boiling point elevation:

ΔTb = Kb x m

ΔTb = 0.512 °C/m x 0.3886 mol/kg

ΔTb = 0.199 °C

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Answer:

Posidonius of Rhodes

Explanation:

The volume at standard pressure will be 293 mL.

To find the volume of gas at standard pressure, we need to use the ideal gas law, which states that PV = nRT, where P is pressure, V is volume, n is the number of moles, R is the gas constant, and T is the temperature.

Since the temperature remains constant, we can rearrange the equation to solve for the volume at standard pressure:

(P₁V₁) / P₂ = V₂

Where P₁ is the initial pressure, V₁ is the initial volume, P₂ is the final pressure (standard pressure), and V₂ is the final volume (what we're solving for).

Plugging in the given values, we get:

(112 kPa)(259 mL) / (1 atm) = V₂

Simplifying and converting units of pressure and volume, we get:

(112000 Pa)(0.259 L) / (1.01325 × 10⁵ Pa) = V₂

Solving for V₂, we get:

V₂ = 0.293 L = 293 mL

Rounding to 3 significant figures, we get that the volume at standard pressure will be 293 mL.

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To solve this problem, we need to use the law of conservation of mass which states that the total mass of reactants equals the total mass of products in a chemical reaction. In this case, we know the mass of the element m and the mass of the compound m3n2 that is produced.

(i) To find the molar mass of the element, we need to first determine the number of moles of the compound produced. We can do this by dividing the mass of the compound by its molar mass.

molar mass of m3n2 = (molar mass of m x 3) + (molar mass of n x 2)
We can find the molar mass of the compound m3n2 by adding the molar mass of three atoms of element m and two atoms of nitrogen. The molar mass of nitrogen is 14 g/mol, and we can use the mass of the compound (43.5 g) to find its molar mass:

molar mass of m3n2 = (molar mass of m x 3) + (molar mass of n x 2)
43.5 g/mol = (3x molar mass of m) + (2x 14 g/mol)
43.5 g/mol - (2x14 g/mol) = 3x molar mass of m
15.5 g/mol = 3x molar mass of m
molar mass of m = 15.5 g/mol / 3 = 5.17 g/mol

So, the molar mass of element m is 5.17 g/mol.

(ii) To find the name of the element, we need to look at the periodic table and find an element with a molar mass close to 5.17 g/mol. From the periodic table, we see that the closest element is boron (B), which has a molar mass of 10.81 g/mol.

Therefore, the element m in this reaction is boron (B).

In summary, we can use the law of conservation of mass and the molar mass of the compound produced to determine the molar mass and name of the element reacted with nitrogen. In this case, we found that the element is boron with a molar mass of 5.17 g/mol.

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Sulfuric acid may act as a catalyst, protonating agent or dehydrating agent in the multi-step experiment where both acetic acid and sulfuric acid are used on day 1.

Sulfuric acid is often used as a catalyst in chemical reactions. In the multi-step experiment where both acetic acid and sulfuric acid are used on day 1, sulfuric acid may act as a catalyst for one or more of the reactions. Sulfuric acid can also protonate certain functional groups in organic compounds, making them more reactive towards other reagents in the reaction mixture.

Additionally, sulfuric acid can act as a dehydrating agent, removing water from the reaction mixture and driving the reaction towards the formation of the desired product. The specific role of sulfuric acid in the multi-step experiment will depend on the nature of the reactions being carried out and the specific reaction conditions.

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--The complete question is, What is the role of sulfuric acid in a multi-step experiment where both acetic acid and sulfuric acid are used on day 1?--

The Tyndall effect is the scattering of light by colloidal particles or suspensions, causing the particles to become visible.

In fog, water droplets act as colloidal particles and scatter light, making it difficult to see clearly. High beams produce a greater amount of light, which causes more scattering and reflection in the fog, resulting in decreased visibility. This is because the water droplets in the fog are closer together and more concentrated in the path of the high beams, causing more light to be reflected back towards the driver's eyes.

Using low beams, on the other hand, produces less light and reduces the amount of scattering and reflection in the fog, resulting in better visibility. Therefore, it is recommended to use low beams when driving in foggy conditions to avoid glare and improve visibility.

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The change in Gibbs free energy for a reaction will be ∆G = 76.8 kJ/mol, as calculated in the below section.

Using the below relationship for change in Gibbs free energy, the change in enthalpy can be calculated as follows.

∆G = ∆H - T∆S

We can use this equation to find ∆H:

∆H = ∆G + T∆S

∆G = -64.76 kJ/mol

T = 132 + 273 = 405K

∆S = 676.54 J/Kmol = 0.677 kJ/Kmol

(change units to match those of ∆G)

∆H = -64.76 + (405)(0.677) = -64.76 + 274

∆H = + 209.4 kJ/mol

Now we can use this to find ∆G at -77.1ºC  (196K)

∆G = ∆H - T∆S

∆G = 209.4 kJ/mol - (196K)(0.677 kJ/Kmol)

∆G = 209.4 - 132.6

∆G = 76.8 kJ/mol

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There are 4.59 × 10²³ ions in 47.8 g of SrF₂.

The mass of 4.90 mol of CuCl₂ · 2H₂O is 0.83495 kg.

The mass of 2.67 × 10²² formula units of Bi(NO₃)₃ · 5H₂O is 1.30 × 10³⁴ mg.

(a) The molar mass of SrF₂ is 125.62 g/mol. Thus, there are 0.380 moles of SrF₂ in 47.8 g. Since each formula unit of SrF₂ produces two ions (Sr²⁺ and 2F⁻), the total number of ions can be calculated by multiplying the number of formula units by the number of ions per formula unit:

0.380 mol SrF₂ × 6.02 × 10²³ formula units/mol × 2 ions/formula unit = 4.59 × 10²³ ions

As a result, there are 4.59 × 10²³  ions in 47.8 g of SrF₂.

(b) The molar mass of CuCl₂ · 2H₂O is 170.48 g/mol. The mass of 4.90 mol of CuCl₂ · 2H₂O can be calculated by multiplying the molar mass by the number of moles:

4.90 mol × 170.48 g/mol = 834.95 g

Since there are 1000 g in 1 kg, 4.90 mol of CuCl₂ · 2H₂O weighs 0.83495 kilogram.

(c) The molar mass of Bi(NO₃)₃ · 5H₂O is 485.09 g/mol. The mass of 2.67 × 10²² formula units of Bi(NO₃)₃ · 5H₂O can be calculated by multiplying the molar mass by the number of formula units:

2.67 × 10²² formula units × 485.09 g/mol = 1.30 × 10²⁷ g

Since there are 10⁶ mg in 1 g, 1.30 × 10³⁴ mg is the mass of 2.67 × 10²² formula units of Bi(NO₃)₃ · 5H₂O.

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The hot pack has a 0.868 J/g°C heat capacity.

To solve this problem, we can use the formula:
q = mcΔT

where q is the heat transferred, m is the mass of the object, c is the specific heat capacity, and ΔT is the change in temperature.

First, let's find the heat transferred by the hot pack to warm up the water:
q = mcΔT
q = (30.0 g)(c)(85°C - 25°C)
q = 20400c J

Next, let's find the heat transferred by the hot pack to warm up the insulated pouch and the food:
q = mcΔT
q = (30.0 g)(c)(40°C - 25°C)
q = 450c J

The total heat transferred by the hot pack is the sum of these two values:
q total = 20400c J + 450c J
q total = 20850c J

Finally, we can use the heat transferred by the hot pack to solve for its specific heat capacity:
q total = mcΔT
20850c J = (30.0 g)(c)(85°C - 25°C) + (30.0 g)(c)(40°C - 25°C)
20850c J = 24000c J
c = 0.868 J/g°C

Therefore, the heat capacity of the hot pack is 0.868 J/g°C.

For more question on heat capacity

https://brainly.com/question/29792498

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