Dissolution of KOH, ΔHsoln:

KOH(s) → KOH(aq) (10.1)
Neutralization of solid KOH, ΔHneut:

KOH(s) + HCl(aq) → H2O(l) + KCl(aq) (10.2)

1) Using Hess's law, show how to combine Reaction 10.1 and Reaction 10.2 to give
KOH(aq) + HCl(aq) → H2O(l) + KCl(aq) (10.3)

2)How should ΔHsoln and ΔHneut be combined (mathematically) to give the change in enthalpy for Reaction 10.3, ΔH?

Considering the definition of percentage by mass and molality, the molality of Na₃PO₄ in the solution is 0.948 [tex]\frac{moles}{kg}[/tex].

The percentage by mass expresses the concentration and indicates the amount of mass of solute present in 100 grams of solution.

In other words, the percentage by mass of a component of the solution is defined as the ratio of the mass of the solute to the mass of the solution, expressed as a percentage.

The percentage by mass is calculated as the mass of the solute divided by the mass of the solution, the result of which is multiplied by 100 to give a percentage. This is:

[tex]percentage by mass=\frac{mass of solute}{mass of solution}x100[/tex]

Molality is the ratio of the number of moles of any dissolved solute to kilograms of solvent.

The Molality of a solution is determined by the expression:

[tex]molality=\frac{number of moles of solute}{kilograms of solvent}[/tex]

Considering 100 grams as a sample of the solution, then the value of the percentage of concentration given indicates that  13.5 g correspond to Na₃PO₄.

Remember that percent concentration by mass is calculated using the mass of solute and the mass of the solution, which includes both the solute and the solvent. Then:

mass solution= mass solute + mass solvent

100 g= 13.5 g + mass solvent

100 g - 13.5 g= mass solvent

86.5 g= mass solvent

Then, you know:

Then, replacing in the definition of molality:

[tex]molality=\frac{0.082 moles}{0.0865 kg}[/tex]

Solving:

molality= 0.948 [tex]\frac{moles}{kg}[/tex]

Finally, the molality of Na₃PO₄ in the solution is 0.948 [tex]\frac{moles}{kg}[/tex].

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Answer:

Radiation causes the metal stick to increase in temperature.

Explanation:

Answer:  

Radiation causes heat from the fire to warm the air.

Explanation:

Considering the Boyle's law, the volume of the balloon at the higher altitude is 7.5 L.

The gas laws are a set of chemical and physical laws that allow determining the behavior of gases in a closed system. The parameters evaluated in these laws are pressure, volume, temperature and moles.

Boyle's law is one of the gas laws that states that the pressure of a gas in a closed container is inversely proportional to the volume of the container, when the temperature is constant. In other words, if the pressure increases, the volume decreases; while if the pressure decreases, the volume increases.

Boyle's law is expressed mathematically as:

P× V = k

In this law then two variables are related: pressure and volume, so it is assumed that the temperature of the gas and the number of molecules of the gas are constant.

Studying an initial state 1 and a final state 2 is fulfilled:

P1× V1= P2× V2

In this case, you know:

Replacing:

1 atm× 6 L= 0.80 atm× V2

Solving:

[tex]V2=\frac{1 atm x 6 L}{0.80 atm}[/tex]

V2= 7.5 L

Finally, the volume of the balloon at the higher altitude is 7.5 L.

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The volume (in liters) that the gas will occupy if the pressure is increased to 13.5 atm and the temperature is decreased to 15 °C is 15 L

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

Initial pressure (P₁) = 8.5 atm

Initial volume (V₁) = 24 L

Initial temperature (T₁) = 25 °C = 25 + 273 = 298 K

Final pressure (P₂) = 13.5 atm

Final temperature (T₂) = 15 °C = 15 + 273 = 288 K

[tex]\frac{P_{1}V_{1}}{T_{1}} = \frac{P_{2}V_{2}}{T_{2}}\\\\\frac{8.5 * 24}{298} = \frac{13.5 * V_{2}}{288}\\\\ \frac{204}{298} = \frac{13.5 * V_{2}}{288}\\\\[/tex]

Cross multiply

298 × 13.5 × V₂ = 204 × 288

4023 × V₂ = 58752

Divide both side by 4023

[tex]V_{2} = \frac{58752}{4023}\\\\[/tex]

Therefore, the final volume of the gas is 15 L

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Answer:

this the partial removal of a substance from a solution or mixture by dissolving it in another immiscible solvent in which it is more soluble.

Answer:

468 g _______________________

The mass of 8 moles of sodium chloride is 468 grams. Therefore, option A is correct.

Molar mass, also known as molecular weight, is the mass of one mole of a substance. It is typically expressed in grams per mole (g/mol). Molar mass is calculated by summing the atomic masses of all the atoms in a molecule.

To calculate the mass of a substance, multiply the number of moles by the molar mass of the substance. The molar mass of sodium chloride (NaCl) is approximately 58.44 grams per mole.

The mass of 8 moles of sodium chloride:

Mass = Number of moles × Molar mass

Mass = 8 moles × 58.44 g/mol

Mass = 467.52 grams

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Answer:

helium

Explanation:

Explanation:

BaF2(s) <------> Ba2+(aq) + 2F-(aq)

Ksp BaF2 =  1.0 x 10^-6.

Ksp BaF2 = [Ba2+(aq)]×[F-(aq)]^2 at equilibrium

When Qsp >Ksp, BaF2 will precipitate

Qsp = [Ba2+(aq)]×[F-(aq)]^2

[Ba2+(aq)]×[F-(aq)]^2 > 1.0 x 10^-6.

0.0122 moldm-3 × [F-(aq)]^2 > 1.0 x 10^-6

[F-(aq)]^2 > 1×10^-6 / 0.0122 mol2dm-6

[F-(aq)]^2 > 81.96 × 10^-6 mol2dm-6

[F- (aq)] > 9.05 × 10^-3 moldm-3

So F- concentration should be more than 9.05 × 10^-3 moldm-3

Answer:

Ideal Gas Law Calculator. Easily calculate the pressure, volume, temperature or quantity in moles of a gas using this combined gas law calculator (Boyle's law calculator, Charles's law calculator, Avogadro's law calculator and Gay Lussac's law calculator in one).Supports a variety of input metrics such as Celsius, Fahrenheit, Kelvin, Pascals, bars, atmospheres, and volume in both metric and

The final volume of the methane gas in the container is 6.67 L.

The given parameters;

The total number of moles of gas in the container is calculated as follows;

[tex]n_t = 0.12 + 0.182 = 0.302 \ mol[/tex]

The final volume of gas in the container is calculated as follows;

[tex]PV = nRT\\\\\frac{V}{n} = \frac{RT}{P} \\\\\frac{V_1}{n_1} = \frac{V_2}{n_2} \\\\V_2 = \frac{V_1 n_2}{n_1} \\\\V_2 = \frac{2.65 \times 0.302}{0.12} \\\\V_2 = 6.67 \ L[/tex]

Thus, the final volume of the methane gas in the container is 6.67 L.

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Answer: specialized body structures of Snakes

Explanation:

Snakes have many adaptations that allow them to move, hunt, eat and survive in their environments. Many animals have developed specific parts of the body adapted to survival in a certain environment. Among them are webbed feet, sharp claws, whiskers, sharp teeth, large beaks, wings, and hooves. In most aquatic animals, swimming is a must. To aid swimming, many animals have adapted and evolved with webbed feet.

Answer:

chlorine

Explanation:

Answer:chlorine reacts with hydrogen peroxide

Explanation:

Answer:

ok

Explanation:

Answer:

1.) 7

2.) 5

3.) stable

4.) 5A

5.) 5

6.) The properties would be more stable to property of phosphorous because same group and valenve electronics and they also have same chemical

Explanation:

The rest i dont know

Answer:

heat the solution

Explanation:

i think

Answer:

The way to make a supersaturated solution is to add heat, but just a little heat won't do the job. You have to heat the water close to the boiling point. When the water gets this hot, the water molecules have more freedom to move around, and there is more space for solute molecules between them.

Yes according to reliable sources.

#let's study

Answer:

where is the question????????????

Answer:

NaHCO3

Explanation:

The three is small at the bottom at the end

Answer:

Step 1-Light Dependent. CO2 and H2O enter the leaf.

Step 2- Light Dependent. Light hits the pigment in the membrane of a thylakoid, splitting the H2O into O2.

Step 3- Light Dependent. ...

Step 4-Light Dependent.

Step 5-Light independent.

Step 6-Light independent.

Iodine is much more easily polarizable than fluorine therefore temporary dipoles in the molecule are strengthened.

The halogens are members of group 17 in the periodic table. They are highly electronegative and seldom occur free in nature owing to their high level of reactivity.

We know that larger molecules are more easily polarized than smaller ones. Therefore, from Fluorine to lodine, the molecular mass increases. The  electron polarizability increases with the mass increase. In turn,  this strengthens the temporary dipole (dispersion) forces  between particles. Hence the properties of halogens change smoothly down the group.

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Answer:

We present a quantitative analysis of global and regional food supply to reveal the flows of calories, protein and the micro-nutrients vitamin A, iron and zinc, from production through to human consumption and other end points. We quantify the extent to which reductions in the amount of human-edible crops fed to animals and, less importantly, reductions in waste, could increase food supply. The current production of crops is sufficient to provide enough food for the projected global population of 9.7 billion in 2050, although very significant changes to the socio-economic conditions of many (ensuring access to the global food supply) and radical changes to the dietary choices of most (replacing most meat and dairy with plant-based alternatives, and greater acceptance of human-edible crops currently fed to animals, especially maize, as directly-consumed human food) would be required. Under all scenarios, the scope for biofuel production is limited. Our analysis finds no nutritional case for feeding human-edible crops to animals, which reduces calorie and protein supplies. If society continues on a ‘business-as-usual’ dietary trajectory, a 119% increase in edible crops grown will be required by 2050.

Explanation:

The mass of steam required to raise the temperature of water is 3.5 g.

The given parameters;

The molar mass of Benzene = 78.11 g/mol

The molar mass of water = 18 g/mol

The number of moles of the Benzene is calculated as follows;

[tex]n = \frac{47.6}{78.11} = 0.61 \ mole[/tex]

The mass of steam required is calculated as follows;

heat lost by steam = heat absorbed by benzene

[tex]\frac{m}{18} \times 40.7 \times 10^3 = 47.6(1.63)(30-5.5) \ + \ 0.61 \times 9.87 \times 10^3\\\\2261.11 m = 7921.61\\\\m = \frac{7921.61}{2261.11} \\\\m = 3.5 \ g[/tex]

Thus, the mass of steam required to raise the temperature of water is 3.5 g.

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it is already balanced

REACTANTS

Barium sulfide (BaS) + platinum (Ii) fluoride

PRODUCT

Barium fluoride (BaF2) + Cooperite (PtS)

Hope this answer helps you dear! take care

Answer:

1. A/Thermal Energy

2. B/The particles within the system will have greater motion, and the temperature will increase.

3. C/Attractions occur due to electrostatic forces. When particles move fast enough, these forces can no longer keep particles together.

4. D/ For a phase change from solid to liquid, the bonds do not break completely and particles can still slide past each other.

5. D/ a sample of liquid benzene at 80ºC and a sample of gaseous benzene at 80ºC

Explanation:

I took the Test.

1. Internal energy associated with systems and particles is thermal energy. Thus, option A is correct.

The internal energy has been described as the energy that has been assessed by the molecules and bonds at the STP. Thermal energy has been the energy of particular molecules and the system comprising all the molecules have the summation of the thermal energy.

Thus, internal energy associated with systems and particles is thermal energy. Thus, option A is correct.

2. The addition of energy results in greater motion with an increase in temperature has been representation no phase change. Thus, option B is correct.

The addition of energy to the substance results in the increased motion of the particles. The energy higher than the threshold energy has been responsible for the phase change of the substance.

The addition of energy results in greater motion with an increase in temperature has been representation no phase change. Thus, option B is correct.

3. The movement of the particles under the gravitational attraction is not enough to hold the particles together at a longer distance. Thus, option B is correct.

The attraction has been the force that has been responsible for holding the particles in a molecule. Different attractions have a different levels of stability and strength.

The movement of the particles under the gravitational attraction is not enough to hold the particles together at a longer distance. Thus, option B is correct.

4. The phase change of the molecules has been mediated by overcoming the force of attraction that allows the molecules to move freely. The solid to liquid phase change has been mediated with the breaking of the attraction between the bonds allowing free movement.

Thus, statement 4 is incorrect, and option D is correct.

5. The kinetic energy has been the energy possessed by the moving molecules in the medium. The molecules in liquid and gas have been possessing the same energy at the same temperature, Thus, option D is correct.

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Answer:

A: Calcium is a group 2 element with two valence electrons. Therefore, it is very reactive and gives up electrons in chemical reactions. It is likely to react with an element with six valence electrons that “wants” to gain two electrons. This would be an element in group 6, such as oxygen.

The balanced molecular chemical equation for the reaction is (NH4)2SO4(aq) + FeCl2(aq) -------> FeSO4(aq) + 2NH4Cl(aq).

The rule for writing a balanced chemical reaction equation is that the number of atom of each element on the right hand side must be the same as the number of atoms of the same element on the left hand side of the reaction equation. This is achieved by performing an atom count.

The balanced molecular chemical equation for the reaction in aqueous solution for ammonium sulfate and iron(II) chloride is;

(NH4)2SO4(aq) + FeCl2(aq) -------> FeSO4(aq) + 2NH4Cl(aq)

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Answer:

18.78%

Hence, the mass percent of lithium in lithium carbonate is 18.78%.

Explanation:

The percent by mass of carbon in this compound,  lithium carbonates  is

16.2%

The compound is lithium carbonates.

The molar mass of the compound will be calculated and the molar mass of carbon in the compound will also be calculated to find the percentage of carbon in it.

Molar mass of  Li₂CO₃ = (7 ×2) + 12 + 48 = 74 g

Molar mass of carbon in the compound = 12g

percentage mass of carbon = 12 / 74 × 100

percentage mass of carbon = 1200 / 74

percentage mass of carbon = 16.2162162162

percentage mass of carbon = 16.2 %

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