Which will evaporate more quickly: 55 mLmL of water in a beaker with a diameter of 4.5 cmcm, or 55 mLmL of water in a dish with a diameter of 12 cmcm ?

Explanation:

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Answer:

pH of HCl solution is 1.44

Explanation:

NaOH is a monoprotic base and HCl is a monobasic acid.

Neutralization reaction: [tex]NaOH+HCl\rightarrow NaCl+H_{2}O[/tex]

According to balanced reaction, 1 mol of NaOH neutralizes 1 mol of HCl.

Number of moles of NaOH in 13 mL of 0.21 M NaOH

= [tex]\frac{0.21}{1000}\times 13mol=0.00273mol[/tex]

let's assume concentration of HCl is C (M)

Then, number of moles of HCl in 75 mL of C (M) HCl solution

= [tex]\frac{75}{1000}\times Cmol=\frac{75C}{1000}mol[/tex]

So, we can write, [tex]\frac{75C}{1000}=0.00273[/tex]

or, [tex]C=0.0364[/tex]

1 mol of HCl contains 1 mol of [tex]H^{+}[/tex]

So, concentration of [tex]H^{+}[/tex] in 0.0364 M HCl, [tex][H^{+}]=0.0364M[/tex]

Hence, [tex]pH=-log[H^{+}]=-log(0.0364)=1.44[/tex]

Answer:

To fulfill octet of B atom in borane, nucleophilic attack by pi electrons of alkene takes place with electrophilic B center in borane.

Explanation:

In Borane ([tex]BH_{3}[/tex]), B atom has energetically vacant 2p orbital and thereby octet is incomplete.Therefore B center in borane act as an electrophilic center.

In alkene, pi bonding electrons are loosely bound together due to side on overlap of two constituent p-orbitals. Hence this pi bond can be easily broken. Alternatively, we can say that pi bond in alkene act as a potential nucleophile.

The first step of hydroboration occurs in a concerted manner where pi electrons of alkene first attack vacant 2p orbital of B in borane to fulfill it's octet (represented by an arrow drawn from alkene to B atom) and forms a 4 memebered cyclic intermediate. Simulaneously, a B-H bond in borane is donated to alkene through 3c-2e bond (3 center-2 electron bond).

Full mechanism has been shown below.  

Answer:

123.1

Explanation:

The average atomic mass of an element which exhibits isotopy is the average mass of its various isotopes as they occur naturally in any quantity of the element.

Average atomic mass = (95% of 123 amu)+(5% 0f 125 amu)

= (0.95 × 123) + (0.05 × 125)

= 116.85 + 6.25

= 123.1   (to 1 decimal place)

Final answer:

To balance the equation RbOH + H3PO4 → Rb3PO4 + H2O, you use the coefficients 3, 1, 1, and 3, resulting in a sum of 8.

Explanation:

The question involves balancing a chemical equation to ensure that the same number of atoms of each element is present on both sides, following the law of conservation of mass. The balanced equation for RbOH + H3PO4 → Rb3PO4 + H2O is 3RbOH + H3PO4 → Rb3PO4 + 3H2O, giving us coefficients 3, 1, 1, 3, and the sum of these coefficients is 8.

It's important to never change the subscripts in a chemical formula while balancing an equation. Instead, coefficients are placed in front of the chemical formulae to indicate the relative amounts of reactants and products. The lowest whole number ratio that balances the equation should be used.

Answer:

The molecular formula is C6H6O2

Explanation:

Step 1: Data given

Suppose the mass of the compound = 100 grams

The compound has:

65.45 % C = 65.45 grams

5.492 % H = 5.49 grams

29.06 % O = 29.06 grams

Molar mass C = 12.01 g/mol

Molar mass H = 1.01 g/mol

Molar mass O = 16.00 g/mol

Molar mass = 110 g/mol

Step 2: Calculate moles

Moles = mass / molar mass

Moles C = 65.45 grams / 12.01 g/mol

Moles C = 5.450 moles

Moles H = 5.49 grams / 1.01 g/mol

Moles H = 5.44 moles

Moles O = 29.06 grams / 16.00 g/mol

Moles O = 1.816 moles

Step 3: Calculate mol ratio

We divide by the smallest amount of moles

Moles C = 5.450 moles / 1.816 = 3

Moles H = 5.44 moles / 1.816 = 3

Moles O = 1.816/1.816 = 1

The empirical formula is C3H3O

The molar mass of this formula is 55 g/mol

We have to multiply the empirical formula by n

n = 110/55 = 2

2*(C3H3O) = C6H6O2

The molecular formula is C6H6O2

The empirical formula for the compound, given the percentage composition and molecular mass, is C3H3O. The molecular formula, given that the molar mass of the compound is about 2.66 times the empirical formula's molar mass, is C9H9O3.

To determine the molecular formula of the compound, we first assume that we have 100g of the compound. This means we have 65.45g of Carbon (C), 5.492g of Hydrogen (H), and 29.06g of Oxygen (O). We must then convert these masses to moles by dividing by the atomic mass (12.01 for C, 1.008 for H, and 16 for O).

Therefore, we have:

We then divide these mole quantities by the smallest obtained mole number to try to get whole numbers. This should give an atomic ratio of 3:3:1 for C, H, and O respectively.

By combining these ratios into a chemical formula, we get C3H3O. This is the empirical formula. The molar mass of this formula (41 g/mol) goes into the given molar mass of the compound (110 g/mol) about 2.66 times, indicating that the true molecular formula of this compound is C9H9O3.

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Answer: 2.53 x 10^-2 moles As ( the answer is in scientific notation )

This is an incomplete question, here is a complete question.

Kp = 0.0198 at 721 K for the reaction:

[tex]2HI(g)\rightleftharpoons H_2(g)+I_2(g)[/tex]

In a particular experiment, the partial pressures of H₂ and I₂ at equilibrium are 0.710 and 0.888 atm, respectively. The partial pressure of HI is __________ atm.

Answer : The partial pressure of HI is, 5.64 atm

Explanation :

For the given chemical reaction:

[tex]2HI(g)\rightleftharpoons H_2(g)+I_2(g)[/tex]

The expression of [tex]K_p[/tex] for above reaction follows:

[tex]K_p=\frac{P_{H_2}\times P_{I_2}}{(P_{HI})^2}[/tex]

We are given:

[tex]P_{H_2}=0.710atm[/tex]

[tex]P_{H_2}=0.888atm[/tex]

[tex]k_p=0.0198[/tex]

Now put all the given values in above equation, we get:

[tex]0.0198=\frac{0.710\times 0.888}{(P_{HI})^2}[/tex]

[tex]P_{HI}=5.64atm[/tex]

Thus, the partial pressure of HI is, 5.64 atm

The correct partial pressure of HI cannot be determined without the accurate initial conditions and changes at equilibrium, since the provided equilibrium partial pressures of H2 and I2 do not match the provided equilibrium constant.

The question states that the partial pressures of H2 and I2 at equilibrium are 0.710 atm and 0.888 atm, respectively, in a reaction H2(g) + I2(g) = 2 HI(g). Given the partial pressure at the start for HI was 1 atm and we are looking to find the equilibrium partial pressure of HI, we can apply the equilibrium constant Kp. However, the values given are part of a typo or irrelevant to the scenario as they do not match with the equilibrium constant Kp provided (1.82  imes 10-2 at 698K), and since such calculations require an accurate accounting of initial conditions and changes at equilibrium, providing an exact value for the partial pressure of HI would be speculative.

Answer:

4.  gives the relative number of atoms of each element per formula unit

Explanation:

An empirical formula -

It refers to the formula which determined the simplest whole - number ratio of all the atoms in a given species , is referred to as an empirical formula .

In simple terms ,

It is he smallest formula of the whole number which when multiplied by some whole number gives the actual structure of the compound .

Hence , from the given information of the question ,

The correct option for empirical formula is 4.

Final answer:

The empirical formula represents the simplest whole-number ratio of atoms of each element in a compound, distinguishing it from the molecular formula which shows the exact number of atoms.

Explanation:

An empirical formula is a representation of the relative number of atoms of each element in a chemical compound, showing the simplest whole-number ratio between the elements. It does not convey the actual numbers of atoms within a molecule but provides a simplified overview of the compound's composition. This characteristic distinguishes it from a molecular formula which details the exact number of atoms of each element present in a molecule. The empirical formula is fundamental in chemistry for understanding the basic composition of a compound and can be derived from the compound's percentage composition.

For example, the empirical formula of water (H2O) indicates that for every oxygen atom, there are two hydrogen atoms, presenting a ratio of 2:1. This reflects the simplest ratio of the atoms within the compound, regardless of how many molecules are present.

Answer:

CH3OH, NaBr, CaCl2, Cr(NO3)3

Based on disorderliness, the ionization strength gives the entropy.

CH3OH - Does not ionize, it's a solvent

NaBr- Ionizes intwo two ions

CaCl2- Ionizes to three ions 1Ca and 2 Cl ions

Cr(NO3)3- Ionizes to four ions

Explanation:

Here is the complete question:.

Rank the following solutes in order of increasing entropy when 0.0100 moles of each dissolve in 1.00 liter of water.

CaCl2, CH3OH, Cr(NO3)3, NaBr

Answer:

Excretory system, and Kidney.

Explanation:

The excretory system helps to regulate the chemical composition of the body fluids by removing metabolic waste such as undigested food, intestinal bacteria, and old cells and helping to retain the proper amount of water, nutrients, and salts in the body.

The main function of the kidney is to filter the blood, kidney help to remove waste from the body as urine, control fluid balance in the body, and keep the right level of electrolytes. Each kidney is bean-shaped in structure and 4-5 inches long in size.

Answer:

= 100kJ

Explanation:

The reverse reaction's activation energy of a reaction is the activation energy of the forward reaction plus ΔH of the reaction:

Ea of forward reaction =75kJ

∆H = -175 kJ/mol

Ea of reverse reaction = 75 +(-175)

= 100kJ

Note that a reverse reaction is one which can proceed in both direction depending on the conditions.

Final answer:

The activation energy for the reverse reaction is calculated using enthalpy change and the activation energy for the forward reaction; it is 250 kJ/mol.

Explanation:

To find the activation energy for the reverse reaction, we can utilize the relationship between the activation energy for the forward reaction (Ea forward), the activation energy for the reverse reaction (Ea reverse), and the enthalpy change (ΔH) of the reaction. The activation energy for a reaction in one direction plus the activation energy for the reverse reaction is equal to the enthalpy change (ΔH) of the overall reaction. Using the given data for the forward reaction: Ea forward = 75 kJ/mol, and ΔH = -175 kJ/mol, we can calculate the activation energy for the reverse reaction using the equation:

Ea reverse = Ea forward - ΔH

Plugging the values into the equation gives:

Ea reverse = 75 kJ/mol - (-175 kJ/mol)

Ea reverse = 75 kJ/mol + 175 kJ/mol

Ea reverse = 250 kJ/mol

Therefore, the activation energy for the reverse reaction is 250 kJ/mol.

Answer:

increase in solvent temperature will increase the solubility of solid particle but decreases the solubility of gas particle.

Explanation:

In solid particle when temperature increases its help to break apart the solid particle and increase in kinetic energy of solvent results in increase in solubility of solid particles in solvent.

but in gas solute, increase in temperature of solvent causes the increase in motion of gas molecules means increase in kinetic energy of molecules in the gas which results in breakage of inter molecular bonds and removal of the molecules from the heated solution.

Answer:

Weaker

Explanation:

The strategy here is to use Raoult´s law to calculate the theoretical vapor pressure for the concentrations given and compare it with the experimental value of 211 torr.

Raoult´s law tell us that for a binary solution

P total = partial pressure A + partial pressure B = Xa PºA + Xb PºB

where Xa and Xb are the mol fractions, and  PºA and PºB are the vapor pressures of pure A and pure B, respectively

For the solution in question we have

Ptotal = 0.312 x 55.3 torr + ( 1- 0.312 ) x 256 torr     ( XA + XB = 1 )

Ptotal = 193 torr

Since experimentally, the total vapor pressure is 211 and our theoretical value is smaller ( 193 torr ), we can conclude the interactions  solute-solvent are weaker compared to the solute-solute and solvent-solvent interactions.

Using Raoult's law, we can conclude that if the actual total vapor pressure of the solution does not match the calculated value, the solution is not ideal. Deviations from the ideal behavior indicate that the solute-solvent interactions differ in strength from solute-solute and solvent-solvent interactions.

To determine if the solution is ideal and to discuss the strengths of solute-solvent interactions compared to solute-solute and solvent-solvent interactions, we can use Raoult's law. Raoult's law states that the partial vapor pressure of each component in an ideal solution is equal to the product of the mole fraction of the component in the liquid phase and the vapor pressure of the pure component.

The expected total vapor pressure for an ideal solution can be calculated by summing the partial pressures of each component. For methanol (CH3OH), with a mole fraction of 1 - 0.312 = 0.688 and a vapor pressure of 256 torr, the expected partial pressure is partial pressure of methanol = 0.688 × 256 torr. For water (H2O), with a mole fraction of 0.312 and a vapor pressure of 55.3 torr, the expected partial pressure is partial pressure of water = 0.312 × 55.3 torr. By adding these two values together, we would get the expected total vapor pressure of an ideal solution.

If the calculated total vapor pressure using Raoult's law does not match the actual total vapor pressure of 211 torr, the solution is not ideal. In that case, the deviation indicates that the solute-solvent interactions differ in strength from the solute-solute and solvent-solvent interactions. If the actual vapor pressure is lower than expected, the solute-solvent interactions are stronger, suggesting a negative deviation. Conversely, a higher actual vapor pressure indicates weaker solute-solvent interactions relative to pure components, leading to a positive deviation.

Answer:

The answer to your question is Miscible

Explanation:

Miscibility is a property to mix in all proportions to fully dissolve in each other at any concentration, forming and homogeneous solution.

Then Miscible substances is when we can combine both liquids in no matter their proportions, we will always obtain a homogeneous mixture.

Two liquids that are soluble in each other in all proportions are termed as miscible, like water and ethanol. Conversely, liquids that do not mix well are immiscible, like oil and water. An intermediary state is partial miscibility, where two liquids have moderate solubility, such as water and bromine.

When two liquids are soluble in each other in all proportions, they are said to be miscible. An example of this is ethanol and water, which blend together completely, regardless of the proportions used. Contrastingly, liquids that do not mix together effectively are deemed immiscible, like oil and water. These tend to form separate layers due to the insufficient attractive forces between their molecules.

A step between these is the state of being partially miscible, which applies when two liquids have moderate mutual solubility. They form two distinct layers when mixed together, as seen when water is combined with bromine. The limit of solubility in each miscibility category (miscible, partially miscible, immiscible) depends on different physical properties and interactions between the molecules of the liquids in question.

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Answer:

Current is 32.8 A

Explanation:

1 mass of Au atom = 3.27×10⁻²⁵kg

Mass of gold = 3.6 kg

We determine the amount of atoms, in that mass of gold therefore we need a rule of three:

3.27×10⁻²⁵kg is the mass for 1 atom

3.6 kg will be the mass for (3.6 . 1)/3.27×10⁻²⁵ = 1.10×10²⁵ atoms

Now we have to find out the total charge of the 3.6 kg of gold so we make another rule of three:

1 atom of Au has a charge of 1.602 × 10⁻¹⁹ C

1.10×10²⁵ atoms of Au will have a charge of (1.10×10²⁵.1.602 × 10⁻¹⁹) / 1 = 1.76×10⁶ C

Formula for the current is: q = i . t

where q is the C, i the value of current and t, time (s)- We make time conversion from h to s

14.88 h . 3600s / 1h = 53568 s  → We replace values:

1.76×10⁶ C  = i . 53568s

1.76×10⁶ C  / 53568s = i → 32.8 A

The molecules CF4 and NF3 have five electron groups arranged in a trigonal bipyramidal fashion. CF4, with four bonded atoms and zero lone pairs, is tetrahedral. NF3, with three bonded atoms and one lone pair, is trigonal pyramidal.

In CF4 and NF3, the five electron groups on the central C and N atoms have a trigonal bipyramidal arrangement. The shapes of the molecules are determined by the number of pairs of electrons: since CF4 has four bonded atoms and zero lone pairs of electrons, the shape is tetrahedral. Since NF3 has three bonded atoms and one lone pair of electrons, the shape is trigonal pyramidal.

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CF4 and NF3 have a tetrahedral electron-pair geometry due to four electron groups on the central atoms. CF4 has a tetrahedral shape due to four bonded atoms and no lone pairs, while NF3 has a trigonal pyramidal shape due to three bonded atoms and one lone pair.

In CF4 and NF3, the four electron groups on the central C and N atoms have a tetrahedral arrangement. The shapes of the molecules are determined by the number of bonded atoms and lone pairs of electrons:

This distinction occurs because although both molecules have a tetrahedral electron-pair geometry, the presence of a lone pair of electrons on nitrogen in NF3 distorts the geometry to be trigonal pyramidal at the molecular level.

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Answer:

[tex]\large \boxed{\text{7.7 kJ}\cdot\text{mol}^{-1} }[/tex]

Explanation:

1. Mass of solution

[tex]\text{Mass of solution} = \text{150 mL} \times \dfrac{\text{1.02 g}}{\text{1 mL}} = \text{153 g}[/tex]

2. Calorimetry

There are two energy flows in this reaction.

q₁ = heat from reaction

q₂ = heat to warm the water

[tex]\begin{array}{ccccl}n\Delta H & + & mC\Delta T &=&0\\\text{0.70 mol}\times \Delta H& + & \text{153 g} \times 4.18 \text{ J}\cdot^{\circ}\text{C}^{-1}\cdot \text{g⁻1} \times (-8.4\, ^{\circ}\text{C}) & = & 0\\0.70\Delta H \text{ mol} & - & \text{5372 J} & = & 0\\& & 0.70\Delta H \text{ mol} & = & \text{5372 J} \\\end{array}[/tex]

[tex]\begin{array}{ccrcl} & & \Delta H & = & \dfrac{\text{ 5372 J}}{\text{0.70 mol}}\\\\ & & & = & \text{7670 J/mol}\\ & & & = & \textbf{7.7 kJ}\cdot\textbf{mol}^{ -\mathbf{-1}} \\\end{array}\\\text{The heat of solution of the compound is $\large \boxed{\textbf{7.7 kJ}\cdot\textbf{mol}^{\mathbf{-1}}}$}[/tex]

The heat of solution is positive, because the water cooled down when the substance dissolved,

To calculate ∆H for the dissolution process, we first calculate the total heat released using the equation q = m × c × ∆T and the provided properties of the solution. We then find ∆H by dividing this total heat by the number of moles of solute, yielding an enthalpy change of -7.57 kJ/mol.

The subject of this question relates to chemistry, specifically the concept of enthalpy change (∆H) in the dissolution of a solid in a solution. The first step to calculating ∆H is determining the total heat absorbed or released during the dissolution, which is calculated using the equation q = m × c × ∆T, where m is the mass of the solution, c is the specific heat capacity, and ∆T is the change in temperature.

In this case, we first convert the volume of the solution to mass by using the provided density of the solution (1.02 g/mL). So, the total mass of the solution is 150 mL × 1.02 g/mL = 153.0 g. Next, using the provided temperature and specific heat, we calculate q = (153.0 g) × (4.18 J/g･°C) × (-8.4°C) = -5300.472 J. We use a negative sign because the temperature decreases, meaning the reaction is exothermic and heat is released.

Finally, we calculate ∆H, the enthalpy change per mole of solute, by dividing q by the number of moles of the solute, 0.70 moles. ∆H = -5300.472 J / 0.70 mol = -7572 J/mol, or -7.57 kJ/mol.

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Answer:

One significant difference between gases and liquids is that a gas expands to fill its container.

Explanation:

One of the biggest differences between liquids and gases is that liquids have a defined volume and gases do not. A gas has no defined shape or volume, it acquires the shape and volume of the container in which it is located. It is the tendency of gases to increase in volume due to the force of repulsion that works between their molecules.

One significant difference between gases and liquids should be that a gas expands to fill its container.

It is the biggest difference that lies between the liquids and gases is that the liquid should contain the volume while the gas does not. Also, the gas does not have a defined shape or volume.

It purchased the shape and the container volume where it should be located.

Also, there is the gas tendency for increasing the volume because of the repulsion of the force that should be worked between the molecules.

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Answer:

a. chain length and degree of saturation.

Explanation:

Fatty acids can be classified according to the length of their chain, for example, in short (if it has less than 8 carbons), medium (between 8-12 carbons), long (between 12-18 carbons) and very long (if it has less than 18 carbons); they are also classified according to their degree of unsaturation, in saturated, monounsaturated and polyunsaturated; and according to the isomerism in cis and trans fatty acids.

Fatty acids may differ from one another in chain length and degree of saturation. Therefore, the correct option is option A.

Fatty acid is a crucial part of lipids, which are the parts of living things including plants, animals, and microbes that may be dissolved in fat. A fatty acid normally consists of a chain that is straight with a even amount of carbon atoms, hydrogen atoms running along the entire length of the chain, a carboxyl group (COOH) at one end, and hydrogen atoms running the duration of the chain. It forms an acid (carboxylic acidic solution) because of the carboxyl group. The acid is saturated if there are only single carbon-to-carbon bonds. Fatty acids may differ from one another in chain length and degree of saturation.

Therefore, the correct option is option A.

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The net ionic equation for the reaction HCN(aq) + KOH(aq) ⟶ H2O(l) + KCN(aq) is: H+ (aq) + OH- (aq) ⟶ H2O(l), after factoring out the spectator ions.

The subject of this question is the net ionic equation for the chemical reaction HCN(aq) + KOH(aq) ⟶ H2O(l) + KCN(aq). First, we write out the full molecular equation. Secondly, we break all aqueous compounds (those in a water solution) down into their ions, resulting in the total or full ionic equation. We then eliminate ions that show up on both sides of the equation as they don't play a part in the actual chemical reaction and are thus 'spectators'. What remains is termed the net ionic equation.

The full molecular equation is: HCN(aq) + KOH(aq) ⟶ H2O(l) + KCN(aq). The full ionic equation is: H+ (aq) + CN- (aq) + K+ (aq) + OH- (aq) ⟶ H2O(l) + K+ (aq) + CN- (aq). From this, the K+ (aq) and CN- (aq) are on both sides and can be eliminated as spectator ions. Thus, the net ionic equation is: H+ (aq) + OH- (aq) ⟶ H2O(l).

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For the reaction [tex]HCN (aq) + KOH (aq) \rightarrow H_2O (l) + KCN (aq)[/tex], the net ionic equation is [tex]HCN (aq) + OH^- (aq) \rightarrow H_2O (l) + CN^- (aq)[/tex] .

For the chemical reaction [tex]HCN (aq) + KOH (aq) \rightarrow H_2O (l) + KCN (aq)[/tex], let's write the net ionic equation including the phases:

First, we'll break down the reaction into its ionic components:

The complete ionic equation is:

[tex]HCN (aq) + K^+ (aq) + OH^- (aq) \rightarrow H_2O (l) + K^+ (aq) + CN^- (aq)[/tex]

Next, we cancel out the spectator ions (K+) to get the net ionic equation:

[tex]HCN (aq) + OH^- (aq) \rightarrow H_2O (l) + CN^- (aq)[/tex]

Answer:

0.098 moles of HNO₃ are present if 4.90×[tex]10^{-2}[/tex] mol of Ba(OH)₂ was needed to neutralize the acid solution

Explanation:

1 mole of Ba(OH)₂ contains 2 moles of OH- ions.

Hence, 0.049 moles of Ba(OH)2 contains x moles of OH- ions.

cross multiplying, we have

1 mole * x mole = 2 moles * 0.049 mole

x mole = 2 * 0.049 / 1

x mole =  0.098 moles of OH- ions.

1 mole of OH- can neutralize 1 mole of H+

Therefore, 0.098 moles of HNO₃ are present if 0.049 moles of Ba(OH)₂ was needed to neutralize the acid solution.

Answer:

The concentration of NaOH in the final solution 0.0584 mole/lit

Explanation:

So Molarity of the solution after mixing [tex]=\frac{0.365}{6.245929} = 0.0584 (M)[/tex]

∴ The concentration of NaOH in the final solution 0.0584 mole/lit

The concentration of NaOH in the final solution is thus 0.0531 M.

To determine the concentration of NaOH in the final solution after 8.4 grams of NaOH are dissolved into 620 mL of 0.250 M NaOH solution, which is then mixed into 1.65 gallons of water, follow these steps:

First, calculate the moles of NaOH initially dissolved. Knowing NaOH has a molar mass of 40.0 g/mol, 8.4 g of NaOH translates to 0.21 moles of NaOH.

Add the moles from the initial 620 mL of 0.250 M solution. That will be 0.250 moles/L * 0.62 L = 0.155 moles.

Combine the moles from both sources for a total of 0.365 moles of NaOH.

Convert 1.65 gallons of water to liters (1 gallon = 3.78541 L), making 1.65 gallons equal to 6.245 liters. Adding this to the initial 0.62 L yields a total final volume of 6.865 liters.

Finally, calculate the final concentration by dividing the total moles of NaOH by the final volume of solution in liters to find the molarity of the final solution.

The concentration of NaOH in the final solution is thus 0.0531 M.

Explanation:

Answer:

The level of hydrogen ion has increased by a factor of 10.

Explanation:

We know, [tex]pH=-log[H^{+}][/tex]

where [tex][H^{+}][/tex] represents concentration of [tex]H^{+}[/tex] in molarity

Here [tex](pH)_{final}=6.5[/tex]

So, [tex][H^{+}]_{final}=10^{-6.5}M[/tex]

Here [tex](pH)_{initial}=7.5[/tex]

So, [tex][H^{+}]_{initial}=10^{-7.5}M[/tex]

Hence, change in pH = [tex]\frac{[H^{+}]_{final}}{[H^{+}]_{initial}}[/tex]  = [tex]\frac{10^{-6.5}M}{10^{-7.5}M}=10[/tex]

So, the level of hydrogen ion has increased by a factor of 10.

Option (B) is correct

Answer:

A. atmospheric CO2 increases

Explanation:

The concentration of CO2 during the Paleozoic era was much higher than the current one, due to geographical factors, but not the chemical composition of the air, which should have been more important in increasing this gas.

The highest concentrations of CO2 during the Paleozoic era occurred during the Cambrian, approximately 7000 ppm (18 times higher than current measurements). During the Late Ordovic Period the CO2 concentration was approximately 12 times higher than the current ones, with a value of 4400 ppm. These high concentrations of CO2 favored the plants colonizing the continents and thus affecting the world climate.

Answer : The number of unpaired electrons in the [tex]F_2^{2+}[/tex] = 2

The bond order of [tex]F_2^{2+}[/tex] is, 2

Explanation :

According to the molecular orbital theory, the general molecular orbital configuration will be,

[tex](\sigma_{1s}),(\sigma_{1s}^*),(\sigma_{2s}),(\sigma_{2s}^*),(\sigma_{2p_z}),[(\pi_{2p_x})=(\pi_{2p_y})],[(\pi_{2p_x}^*)=(\pi_{2p_y}^*)],(\sigma_{2p_z}^*)[/tex]

As there are 9 electrons present in fluorine.

The number of electrons present in [tex]F_2^{2+}[/tex] molecule = 2(9) = 18 - 2 = 16

The molecular orbital configuration of [tex]F_2^{2+}[/tex] molecule will be,

[tex](\sigma_{1s})^2,(\sigma_{1s}^*)^2,(\sigma_{2s})^2,(\sigma_{2s}^*)^2,(\sigma_{2p_z})^2,[(\pi_{2p_x})^2=(\pi_{2p_y})^2],[(\pi_{2p_x}^*)^1=(\pi_{2p_y}^*)^1],(\sigma_{2p_z}^*)^0[/tex]

The number of unpaired electrons in the [tex]F_2^{2+}[/tex] = 2

The formula of bond order = [tex]\frac{1}{2}\times (\text{Number of bonding electrons}-\text{Number of anti-bonding electrons})[/tex]

The bonding order of [tex]F_2^{2+}[/tex] = [tex]\frac{1}{2}\times (10-6)=2[/tex]

The bond order of [tex]F_2^{2+}[/tex] is, 2

Answer:

Work done in this process = 4053 J

Explanation:

Mass of the gas = 0.092 kg

Pressure is constant = 1 atm = 101325 pa

Initial temperature [tex]T_{1}[/tex] = 200 K

Final temperature [tex]T_{2}[/tex] = 200 - 85 = 115 K

Gas constant for nitrogen = 297 [tex]\frac{J}{kg k}[/tex]

When pressure of a gas is constant, volume of the gas is directly proportional to its temperature.

⇒ V ∝ T

⇒ [tex]\frac{V_{2} }{V_{1} }[/tex] = [tex]\frac{T_{2} }{T_{1} }[/tex] ------------ ( 1 )

From ideal gas equation [tex]P_{1}[/tex] [tex]V_{1}[/tex] = m R [tex]T_{1}[/tex] ------ (2)

⇒ 101325 × [tex]V_{1}[/tex] = 0.092 × 297 × 200

⇒ [tex]V_{1}[/tex] = 0.054 [tex]m^{3}[/tex]

This is the volume at initial condition.

From equation 1

⇒ [tex]\frac{V_{2} }{0.054}[/tex] = [tex]\frac{200}{115}[/tex]

⇒ [tex]V_{2}[/tex] = 0.094 [tex]m^{3}[/tex]

This is the volume at final condition.

Thus the work done is given by W = P [[tex]V_{2}[/tex] - [tex]V_{1}[/tex] ]

⇒ W = 101325 × [ 0.094 - 0.054]

⇒ W = 4053 J

This is the work done in that process.

Explanation:

Answer:

Photosynthesis

Explanation:

As the plants are converting the CO2 into O2... So the photosynthesis reduce the amount of CO2...

Answer:

The answer is photosynthesis

Explanation:

The key processes of the carbon cycle are when the carbon dioxide from the atmosphere is changed into plant material in the biosphere by photosynthesis.

Then organisms in the biosphere obtain energy from respiration and releases carbon dioxide that was orignally changed by photosynthesis.