For which of the following reactions is ΔH∘rxn equal to ΔH∘f of the product(s)?
You do not need to look up any values to answer this question.
Check all that apply.
Check all that apply.
C(s,graphite)+O2(g)→CO2(g)
Li(s)+12F2(l)→LiF(s)
CO(g)+12O2(g)→CO2(g)
BaCO3(s)→BaO(s)+CO2(g)
2Li(s)+F2(g)→2LiF(s)
Li(s)+12F2(g)→LiF(s)

The formation of oxygen in the reaction, the absorption of 361 kJ of heat takes place.

The heat of formation of oxygen will be

[tex]\rm \Delta H[/tex] is +824.2 kJ.

The positive sign of H denotes that the reaction accepts energy from the surroundings. It is an endothermic reaction.

In the reaction the % formation of Oxygen is :

Total product formed = 7 moles

Oxygen formed = 3 moles

% Oxygen formed = [tex]\rm \frac{3}{7}\;\times\;100[/tex]

% oxygen formed  = 42.85 %

The total enthalpy for the formation of product is +824.2 kJ.

The enthalpy for the formation of 42.85 % Oxygen = +824.2 [tex]\times[/tex] 42.85 / 100 kJ.

The enthalpy of the formation of oxygen in the reaction will be 353.22 kJ.

The closest is 361 kJ.

So, for the formation of oxygen in the reaction, the absorption of 361 kJ of heat takes place.

For more information, refer the link:

https://brainly.com/question/12902391?referrer=searchResults

The molar mass of an element is equal to the element's atomic weight mentioned in the periodic table.

Molar mass of a compound or a molecule is defined as the mass of the elements which are present in it.The molar mass is considered to be a bulk quantity not a molecular quantity. It is often an average of the of the masses at many instances.

The molecular mass and formula mass are used as synonym for the molar mass.It does not depend on the amount of substance which is present in the sample.It has units of gram/mole.

Molar masses of an element are given as relative atomic masses while that of compounds is the sum of relative atomic masses which are present in the compound.The element's molar mass is mentioned in the box of the element's symbol in the periodic table.

Learn more about molar mass,here:

https://brainly.com/question/12127540

#SPJ6

The number of particles in A is 1.506 x 10²³, in B is 5.156 x 10²⁰, in C is 2.131 x 10²⁵, and in D is 2.559 x 10²³.

To determine the number of particles in each of the following substances, it is required to use Avogadro's number, which is 6.022 x 10²³ particles per mole. We can use dimensional analysis, also known as the unit conversion method, to convert from moles to particles.

A. 0.250 mol silver

Number of particles = 0.250 mol x 6.022 x 10²³ particles/mol

Number of particles = 1.506 x 10²³ particles

B. 8.56 x 10⁻³ mol NaCl

Number of particles = 8.56 x 10⁻³ mol x 6.022 x 10²³ particles/mol

Number of particles = 5.156 x 10²⁰ particles

C. 35.4 mol CO₂

Number of particles = 35.4 mol x 6.022 x 10²³ particles/mol

Number of particles = 2.131 x 10²⁵ particles

D. 0.425 mol N₂

Number of particles = 0.425 mol x 6.022 x 10²³ particles/mol

Number of particles = 2.559 x 10²³ particles

Therefore, there are approximately 1.506 x 10²³ particles in 0.250 mol of silver, 5.156 x 10²⁰ particles in 8.56 x 10⁻³ mol of NaCl, 2.131 x 10²⁵ particles in 35.4 mol of CO₂, and 2.559 x 10²³ particles in 0.425 mol of N₂.

Learn more about moles, here:

https://brainly.com/question/26416088

#SPJ2

Answer: The average atomic mass of Strontium is 87.65 u

Explanation:

Average atomic mass of an element is defined as the sum of masses of each isotope each multiplied by their natural fractional abundance.

Formula used to calculate average atomic mass follows:

[tex]\text{Average atomcic mass }=\sum_{i=1}^n\text{(Atomic mass of an isotopes)}_i\times \text{(Fractional abundance})_i[/tex]     .....(1)

Mass of [tex]_{38}^{86}\textrm{Sr}[/tex] isotope = 85.91 u

Percentage abundance of [tex]_{38}^{86}\textrm{Sr}[/tex] isotope = 9.46 %

Fractional abundance of [tex]_{38}^{86}\textrm{Sr}[/tex] isotope = 0.09460

Mass of [tex]_{38}^{87}\textrm{Sr}[/tex] isotope = 86.91 u

Percentage abundance of [tex]_{38}^{87}\textrm{Sr}[/tex] isotope = 7.00 %

Fractional abundance of [tex]_{38}^{87}\textrm{Sr}[/tex] isotope = 0.0700

Mass of [tex]_{38}^{88}\textrm{Sr}[/tex] isotope = 87.91 u

Percentage abundance of [tex]_{38}^{88}\textrm{Sr}[/tex] isotope = 83.54 %

Fractional abundance of [tex]_{38}^{88}\textrm{Sr}[/tex] isotope = 0.8354

Putting values in equation 1, we get:

[tex]\text{Average atomic mass of Sr}=[(85.91\times 0.0946)+(86.91\times 0.0700)+(87.91\times 0.8354)][/tex]

[tex]\text{Average atomic mass of Sr}=87.65u[/tex]

Hence, the average atomic mass of Strontium is 87.65 u

Answer:

- Both of their valence electrons are at p subshell.

- They have the first subshell full of electrons.

- Both of them have just 1 electron at the last p subshell.

Explanation:

Hello,

In this case, we could understand their electron structures by identifying their electron configurations as shown below:

[tex]B^5\rightarrow 1s^2,2s^2,2p^1\\Al^{13}\rightarrow 1s^2,2s^2,2p^6,3s^2,3p^1[/tex]

In such a way, we could notice the following similarities:

- Both of their valence electrons are at p subshell.

- They have the first subshell full of electrons.

- Both of them have just 1 electron at the last p subshell.

Best regards.

The molecular formula of the hydrocarbon is C4H8.

The molecular formula of the hydrocarbon can be determined using the given information. Since the compound is 82.66% carbon by mass, we can assume that the remaining percentage is hydrogen. The molar mass of the compound is 58.12 g/mol.

To find the molecular formula, we need to determine the empirical formula first. We assume 100 g of the compound, so 82.66 g is carbon and 17.34 g is hydrogen. Using the molar mass and the atomic masses of carbon and hydrogen, we can determine the moles of each element.

The empirical formula is CH2, and the molar mass of CH2 is 14.03 g/mol. To find the molecular formula, we divide the molar mass of the compound (58.12 g/mol) by the molar mass of CH2 (14.03 g/mol). The result is approximately 4.15. We round this to the nearest whole number, which gives us a molecular formula of C4H8.

https://brainly.com/question/28647690

#SPJ11

The concentration of the solution made by dissolving 25.00 g of CuCl2 in enough water to make 250 mL of solution is 0.74 M.

In this question, we are dealing with molarity calculation. The molarity of a solution is determined by the formula: Molarity (M) = moles of solute/volume of solution in liters. But first, we need to convert the mass of CuCl2 into moles. CuCl2 has a molar mass of about 134.45 g/mol. So, we divide 25.00 g CuCl2 by 134.45 g/mol which equals 0.185 moles. The volume of the solution is 250 mL, which we convert to liters to match the units in the molarity formula. This gives us 0.250 L. We now substitute these values into the molarity formula - M = 0.185 moles/0.250 L = 0.74 M. Therefore, the concentration of the solution is 0.74 M.

https://brainly.com/question/8732513

#SPJ12

6.02 x 10^6 is correct it's not negative because youre moving in the positive direction in terms of sci not.

Answer: Option (c) is the correct answer.

Explanation:

When current passes through a wire then a magnetic field is formed. Therefore, when two wires carry current in the same direction then both the wires with have respective magnetic fields in the same direction and their total magnetic field will be large.

But when current between two wires flow in opposite direction then the magnetic field produced will also be in opposite direction. Therefore, both the magnetic fields cancel each other out. Thus, total magnetic field will be small.

As a result, wires which carry current in the opposite direction repel each other.

Among the compounds NaNO2, KHSO4, KBr, and Ba(NO3)2, KHSO4 forms an acidic solution when dissolved in water. It can donate a proton, subsequently increasing the concentration of hydronium ions. The other compounds do not result in an increased concentration of hydronium ions and thus, do not form acidic solutions.

When you're determining which of these compounds--NaNO2, KHSO4, KBr, Ba(NO3)2--forms an acidic solution when dissolved in water, it's important to understand how compounds behave in water. Most notably, you should know that an acidic solution contains a greater concentration of hydronium ions (H3O+) than hydroxide ions (OH-).

Sulfuric acid is a diprotic acid, which means it can donate two protons. It forms both sulfates and hydrogen sulfates in solution, and most of these compounds moderate the pH when dissolved in water. Consequently, KHSO4 is the compound that will result in an acidic solution, since upon dissolution, it can donate a proton and thereby increase the concentration of H3O+ ions.

As a note, the other compounds listed (NaNO2, KBr, Ba(NO3)2) do not increase the concentration of H3O+ ions; thus, they won't form acidic solutions. For instance, Ba(NO3)2 in a neutralization reaction with water will form a neutral salt and water.

https://brainly.com/question/28982585

Answer:

Increasing the temperature Decreases the humidity and vice versa

Explanation:

When the temperature is increasing, the air can hold more water molecules ,thereby making the humidity to reduce. A high humidity will make the weather to be more hotter because the body sweat will not evaporate easily. A low humidity makes the weather cooler due to the fact the body sweat evaporate easily .

The final temperature of the water : 30.506 °C

The law of conservation of energy can be applied to heat changes, i.e. the heat received / absorbed is the same as the heat released  

Qin = Qout  

Heat can be calculated using the formula:  

Q = mc∆T  

m = mass, g  

∆T = temperature difference, °C / K  

From reaction:  

2C₆H₆ (l) + 15O₂ (g) ⟶12CO₂ (g) + 6H₂O (l) +6542 kJ, heat released by +6542 kJ to burn 2 moles of C₆H₆

If there are 5.400 g of C₆H₆ then the number of moles:  

mol = mass: molar mass C₆H₆

mol = 5.4 : 78  

mol C₆H₆ = 0.0692

so the heat released in combustion 0.0692 mol C₆H₆:  

[tex]\rm Q=heat=\dfrac{0.0692}{2}\times 6542\:kJ\\\\Q=226.353\:kJ[/tex]

the heat produced from the burning is added to 5691 g of water at 21 C

So :

Q = m . c . ∆T (specific heat of water = 4,186 joules / gram ° C)  

226353 = 5691 . 4.186.∆T  

[tex]\rm \Delta T=\dfrac{226353}{5691\times 4.186}\\\\\Delta T=9.506\\\\\Delta T=T(final)-Ti(initial)\\\\9.506=T_f-21\\\\T_f=30.506\:C[/tex]  

the difference between temperature and heat  

brainly.com/question/3821712  

Specific heat  

brainly.com/question/9525136  

relationships among temperature, heat, and thermal energy.  

brainly.com/question/224374  

When heat is added to a substance  

brainly.com/question/3417580  

Final answer:

To calculate the equilibrium constant for the reaction NO− 2 (aq) + H2O(l) → HNO2(aq) + OH−(aq), reverse the first given reaction, H3O+ + NO− 2 → HNO2 + H2O with Kc = 3.86 × 10³, and divide by the autoionization constant of water, Kw = 1.0 × 10−14, to obtain Kc = 3.86 × 10³17.

Explanation:

To calculate the equilibrium constant (Kc) for the chemical reaction NO− 2 (aq) + H2O(l) → HNO2(aq) + OH−(aq), we need to use the given equilibrium constants for related reactions and the autoionization of water.

The first reaction is:

The second reaction is the autoionization of water:

By reversing the first reaction and dividing its Kc by Kw, we can obtain the equilibrium constant for the reaction NO− 2 (aq) + H2O(l) → HNO2(aq) + OH−(aq):

Diffusion of nonpolar molecules is does not affected by charge. Because they have no partial charges. Hence option d is correct.

Diffusion of substance is the spreading or transfer of compounds based on concentration gradient or pressure gradient. Molecules diffuses from higher concentration region to lower concentration region.

Non-polar molecules are those which have no permanent dipole moment. They have no partial charges formed during chemical bonding. Whereas, polar compounds are those having permanent dipole moment and are having partial charges.

All other factors, such as temperature, pressure, concentration and molecular size will affect the rate of diffusion. Thus for non-polar compounds charge is  affecting the diffusion.

To find more about diffusion, refer the link:

https://brainly.com/question/24746577

#SPJ2

Your question is incomplete but your complete question probably was:

Diffusion of nonpolar molecules would not be affected by

a.molecule size.

b.steepness of the concentration gradient.

c.temperature.

d.charge.

e.steepness of the pressure gradient

The final concentration of the solution after the described dilution process is approximately 0.00855 M.

Let's first ascertain the original dilution's concentration. Using the dilution equation:

Where:

Since 0 ml is a typo, let us assume the starting volume V₁ is enough such as 1 mL. Plugging in the values:

Now, calculate the concentration after the second dilution:

Using the intermediate solution:
[tex]C_1V_1 = C_2V_2[/tex]

The final concentration after the second dilution is about 0.00855 M.

Answer is: final volume is 4.21 liters.

Use Avogadro's Law (the Volume Amount Law): If the amount of gas in a container is increased, the volume increases.

The volume-amount fraction will always be the same value if the pressure and temperature remain constant.

V₁ / n₁ = V₂ / n₂.

2.46 l / 0.158 mol =  V₂ / 0.271 mol.

V₂ = 4.21 l.

To find the final volume of the balloon, we can use the combined gas law equation. The initial pressure is calculated using the number of moles and volume. This pressure, along with the final number of moles, initial volume, and constant temperature, can be used to find the final volume.

To solve this problem, we can use the combined gas law equation (P1V1/T1 = P2V2/T2) which relates the pressure, volume, and temperature of a gas. Since the temperature and pressure remain constant, we can use the equation to find the final volume. First, calculate the initial pressure by dividing the number of moles by the volume. Then substitute the initial pressure, final number of moles, and initial volume into the equation, and solve for the final volume.

Given:

N1 = 0.158 mol

N2 = 0.113 mol

V1 = 2.46 L

V2 = ?

P1 = N1/V1

Substituting the values:

P1 = 0.158 mol / 2.46 L = 0.0642 atm

Now, substitute the values into the combined gas law equation:

P1V1/T1 = P2V2/T2

Solving for V2:

V2 = (P1V1T2) / (P2T1)

Since the temperature and pressure remain constant, we can write the equation as:

V2 = (P1V1) / P2

Substituting the values:

V2 = (0.0642 atm * 2.46 L) / (0.113 mol) = 1.396 L

The final volume of the balloon is 1.396 L.

https://brainly.com/question/30458409

#SPJ3

Final answer:

Hydrogen bonding in acids, solvation energy terms, and the impact of strong acids on conjugate bases are crucial concepts in understanding acid dissociation and acid-base behavior in solution.

Explanation:

Hydrogen bonding occurs when a hydrogen atom, part of a polar covalent bond, is bonded to a more electronegative atom. In the case of acids, hydrogen bonds form between the hydrogen atom of the acid (H-A) and water molecules. This results in the acid dissociation process, where the acid molecule becomes an anion.

Solvation energy terms play a crucial role in driving hydrogen ion transfer in solution. Despite thermodynamic considerations indicating that most strong Brønsted acids should not act as acids towards water, solvation energy terms, aided by entropic effects, drive hydrogen ion transfer in solution.

In general, strong acids form very weak conjugate bases, while weak acids form stronger conjugate bases. Water has a leveling effect on dissolved acids, generating hydronium and hydroxide ions, the strongest acid and base in water.

that's the answer comparison with standard mass units

Hello!

comparison with standard mass units

is your answer

The estimated effective nuclear charge (Zeff) experienced by an electron in the 3p orbital of a chlorine atom is approximately 7, as inner electrons shield the nucleus' full charge of 17. This is derived from considering the electron configuration of chlorine and the shielding effects provided by inner electrons.

The question is asking about the effective nuclear charge (Zeff) experienced by an electron in the 3p orbital of a chlorine atom. The effective nuclear charge is the net positive charge an electron feels after accounting for the shielding effect of the other electrons. A neutral chlorine atom has an atomic number of 17, which means there are 17 protons in the nucleus. However, the effective nuclear charge felt by an electron in the 3p orbital is not the full charge of 17 due to the shielding of the electrons in closer orbitals.

The electron configuration of a neutral chlorine atom is 1s22s22p63s23p5. The 10 electrons in the 1s, 2s, and 2p orbitals shield the 3p electrons from the full nuclear charge. Using Slater's rules, one can estimate the effective nuclear charge felt by a 3p electron. The value of Zeff is typically between 1 and the actual nuclear charge (Z), which is 17 for chlorine. The exact Zeff would require taking into account the actual amount of shielding provided by the inner electrons, which tends to be a complex calculation considering electron-electron interactions and the distribution of electron density.

However, based on Slater's rules and shielding effects, a rough estimate for the Zeff would be closer to the chlorine's atomic number (17) than to 1, making options a (-1) and b (5) incorrect. Since the 10 inner electrons shield the nuclear charge, a reasonable estimate for Zeff for a 3p electron in chlorine might be around 7 (17 nuclear charge - 10 shielding electrons), but advanced calculations are required for a precise value. Therefore, answer choice c (7) seems to be the most appropriate estimate based on basic principles.

https://brainly.com/question/33631338

#SPJ3