5.00 mL is withdrawn from a 1.00L solution of NaCl and diluted to 100.00 mL. If the concentration of the NaCl in the 100.00 mL solution is 0.076, what is the concentration of NaCl in the original 1.00 L solution? answers

Answer: There are now 2.07 moles of gas in the flask.

Explanation:

[tex]PV=nRT[/tex]

P= Pressure of the gas = 697 mmHg = 0.92 atm  (760 mmHg= 1 atm)

V= Volume of gas = volume of container = ?

n = number of moles = 1.9

T = Temperature of the gas = 21°C=(21+273)K= 294 K   (0°C = 273 K)

R= Value of gas constant = 0.0821 Latm\K mol

[tex]V=\frac{nRT}{P}=\frac{1.9\times 0.0821 \times 294}{0.92}=49.8L[/tex]

When more gas is added to the flask. The new pressure is 775 mm Hg and the temperature is now 26 °C, but the volume remains same.Thus again using ideal gas equation to find number of moles.

[tex]PV=nRT[/tex]

P= Pressure of the gas = 775 mmHg = 1.02 atm  (760 mmHg= 1 atm)

V= Volume of gas = volume of container = 49.8 L

n = number of moles = ?

T = Temperature of the gas = 26°C=(26+273)K= 299 K   (0°C = 273 K)

R= Value of gas constant = 0.0821 Latm\K mol

[tex]n=\frac{PV}{RT}=\frac{1.02\times 49.8}{0.0821\times 299}=2.07moles[/tex]

Thus the now the container contains 2.07 moles.

To find the new amount of moles after adding gas to the flask, the combined gas law was used, leading to the calculation that there are now 2.126 moles of gas in the flask.

The subject of the student's question is Chemistry, and it involves applying the ideal gas law to determine the amount of gas in moles after a change in pressure and temperature. To solve the problem, we can use the combined gas law which is derived from the ideal gas law: PV = nRT. Considering that the volume and the R (ideal gas constant) do not change, we can compare the two states of the gas with the formula P1/T1 = P2/T2. Here, pressure is given in mm Hg and temperature in degrees Celsius, which we need to convert to Kelvin by adding 273.15.

First state (before adding more gas):

P1 = 697 mm Hg

T1 = 21°C + 273.15 = 294.15 K

n1 = 1.9 moles

Second state (after adding more gas):

P2 = 775 mm Hg

T2 = 26°C + 273.15 = 299.15 K

The number of moles in the second state (n2) is what we want to find. Using the combined gas law:

P1 / T1 = P2 / T2 × (n2 / n1)

n2 = P1 × T2 / (P2 × T1) × n1

n2 = (697 mm Hg × 299.15 K) / (775 mm Hg × 294.15 K) × 1.9 mol

n2 = 2.126 mol

There are now 2.126 moles of gas in the flask.

Answer: 0.028 grams

Explanation:

Depression in freezing point :

Formula used for lowering in freezing point is,

[tex]\Delta T_f=k_f\times m[/tex]

or,

[tex]\Delta T_f=k_f\times \frac{\text{ Mass of solute in g}\times 1000}{\text {Molar mass of solute}\times \text{ Mass of solvent in g}}[/tex]

where,

[tex]\Delta T_f[/tex] = change in freezing point

[tex]k_f[/tex] = freezing point constant  (for benzene} =[tex]5.12^0Ckg/mol[/tex]

m = molality

Putting in the values we get:

[tex]0.400^0C=5.12\times \frac{\text{ Mass of solute in g}\times 1000}{354.5\times 209.0}[/tex]

[tex]{\text{ Mass of solute in g}}=0.028g[/tex]

0.028 grams of DDT (solute) must be dissolved in 209.0 grams of benzene to reduce the freezing point by 0.400°C.

Answer:

6.9

Explanation:

A weak acid dissociates in an equilibrium reaction, thus, it is in equilibrium with its conjugate base:

HA ⇄ H⁺ + A⁻

The equilibrium constant (Ka) can be calculated, where Ka = [H⁺]*[A⁻]/[HA]. Using the -log form, we can also have pKa = -logKa. By the Handerson-Halsebach (HH) equation, the relation between pH and pKa is:

pH = pKa + log[A⁻]/[HA]

So, when pH = 5.7, for this acid, the ratio of [acid]/[base] ([HA]/[A-]) is:

5.7 = 6.3 + log[A⁻]/[HA]

log[A⁻]/[HA] = -0.6

log[HA]/[A⁻] = 0.6

[HA]/[A⁻] = [tex]10^{0.6}[/tex]

[HA]/[A⁻] = 3.98 = 4.0

If the ratio of acid and base is 4 to 1, it means that 80%(4/5) of the acid is protonated after the addition of the HCl.

The initial number of moles of the weak acid was: 100 mL * 0.10 M = 10 mmol, so after the addition of HCl, 8 mmol is in the acid form (80% of 10). It was added 6.0 mmol of HCl (6.0 mL*1.0M). Thus, 6.0 mmol of H+ was added and reacted with the conjugate base of the weak acid.

For the mass conservation, the initial amount of the protonated weak acid must be 2.0 mmol (8 - 6), and the number of moles of the conjugate base was 8.0 mmol. Using the HH equation:

pH = 6.3 + log(8/2)

pH = 6.3 + 0.6

pH = 6.9

The original pH of the weak acid solution was 6.3 which can be determined using the pKa value and the Henderson-Hasselbalch equation. The addition of HCl does not affect this original pH.

A weak acid's initial pH can be calculated using the pKa of the acid and its initial concentration (0.10 M in this case) through the Henderson-Hasselbalch equation: pH = pKa + log ([A-]/[HA]). However, a weak acid exists in equilibrium with its conjugate base and there is no added base here initially, so the pH equals the pKa, making the original pH 6.3. The addition of HCl doesn't matter in this context because the question asks for the original pH, not the final pH.

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In the redox reaction, Mg gets oxidized and Cl2 gets reduced. The oxidizing agent is Cl- and the reducing agent is Mg.

In the redox reaction: Mg(s) + Cl2(g) → Mg2+(aq) + 2Cl-(aq), the substance that gets oxidized is Mg(s) and the substance that gets reduced is Cl2(g). The oxidizing agent is Cl- and the reducing agent is Mg(s).

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Answer:

[tex]\boxed{1.33 \times 10^{-5}\, \text{mol/L}}}[/tex]

Explanation:

Data:

           c₀ = 1.33 mol·L⁻¹

Dilutions = 2 mL stock + 18 mL water

            n = five dilutions

Calculations:

The general formula is for calculating a single dilution ratio (DR) is

[tex]DR = \dfrac{V_{i}}{V_{f}}[/tex]

For your dilutions,

[tex]V_{i} = \text{2 mL}\\V_{f} = \text{20 mL}\\DR = \dfrac{ \text{2 mL}}{\text{20 mL}} = \dfrac{1}{10}[/tex]

(Note: This is the same as a dilution factor of 10:1)

The general formula for the concentration cₙ after n identical serial dilutions is

[tex]c_{n} = c_{0}(\text{DR})^{n}[/tex]

So, after five dilutions

[tex]c_{5} =1.33 \left (\dfrac{1}{10} \right )^{5}=1.33\left ( \dfrac{1}{10^{5}} \right ) = \mathbf{1.33 \times 10^{-5}}\textbf{ mol/L}\\\\\text{The final concentration is $\boxed{\mathbf{1.33 \times 10^{-5}\, mol/L}}$}[/tex]

Answer : The amount of air added to the tank will be, 1.2062 Kg.

Explanation :

First we have to calculate the volume of air by using ideal gas equation.

[tex]P_1V_1=\frac{m_1RT_1}{M}[/tex]

where,

[tex]P_1[/tex] = initial pressure of air = [tex]20psia=1.36atm[/tex]

conversion used : [tex]1psia=0.068046atm[/tex]

[tex]T_1[/tex] = initial temperature of air = [tex]70^oF=294.261K[/tex]

conversion used : [tex](70^oF-32)\frac{5}{9}+273.15=294.261K[/tex]

[tex]V_1[/tex] = initial volume of air = ?

[tex]m_1[/tex] = initial mass of air = [tex]20Ibm=9071.85g[/tex]

conversion used : [tex]1lbm=453.592g[/tex]

R = gas constant = 0.0821 L.atm/mole.K

M = molar mass of air

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

[tex](1.36atm)\times V_1=\frac{(9071.85g)\times (0.0821L.atm/mole.K)\times (294.261K)}{M}[/tex]

[tex]V_1=\frac{161150.9299}{M}L[/tex]

Now we have to calculate the final amount of air by using ideal gas equation.

[tex]P_2V_2=\frac{m_2RT_2}{M}[/tex]

where,

[tex]P_2[/tex] = final pressure of air = [tex]23.5psia=1.599atm[/tex]

[tex]T_2[/tex] = final temperature of air = [tex]90^oF=305.37K[/tex]

[tex]V_2[/tex] = final volume of air = [tex]V_1=\frac{161150.9299}{M}L[/tex]

[tex]m_2[/tex] = final mass of air = ?

R = gas constant = 0.0821 L.atm/mole.K

M = molar mass of air

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

[tex](1.599atm)\times (\frac{161150.9299}{M}L)=\frac{m_2\times (0.0821L.atm/mole.K)\times (305.37K)}{M}[/tex]

[tex]m_2=10278.074g[/tex]

Now we have to calculate the amount of air added to the tank.

[tex]m_2-m_1=10278.074g-9071.85g=1206.224g=1.2062Kg[/tex]

conversion used : (1 Kg = 1000 g)

Hence, the amount of air added to the tank will be, 1.2062 Kg.

The relation between the volume, the pressure, and the temperature is PV = mRT. Then the amount of air added to the tank is 1.2062 kg.

What is thermodynamics?

It is a branch of science that deals with heat and work transfer.

A rigid tank contains 20 lbm of air at 20 psi and 70°F. More air is added to the tank until the pressure and temperature rise to 23.5 psi and 90°F, respectively.

The ideal gas equation is

[tex]PV = \dfrac{mRT}{M}[/tex]

[tex]P_1 = 20 \ psi = 1.36 \ atm\\\\T_1 = 70 ^oF = 294.261\ K\\\\V_1 = \ \ ? \\\\m_1 = 20 \ lbm = 9071.85 \ kg[/tex]

R = 0.0821 L atm/mole K

M = molar mass of air

Now put all the given values in the ideal gas equation, we have

[tex]\rm V_1 = \dfrac{9071.85*0.0821*294.261}{1.36M}\\\\\\V_1 = \dfrac{161150.8299}{M}[/tex]

Now we have to calculate the final amount of air by using an ideal gas equation, we have

[tex]P_2 = 23.5 \ psi = 1.599\ atm\\\\T_2 = 90^oF = 305.37\ K\\\\V_2 = V_1\\\\m_2 = \ \ ?[/tex]

Then we have

[tex]m_2 = \dfrac{1.599M* \dfrac{161150.9299}{M}}{0.0821*305.37}\\\\m_2 = 10278.074 \ g[/tex]

Now we have to calculate the amount of air added to the tank will be

⇒ m₂ - m₁ = 10278.074 - 9071.85 = 1206.244 g = 1.12062 kg

Hence, the amount of air added to the tank is 1.2062 kg.

More about the thermodynamics link is given below.

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Explanation:

It is known that acetic acid is a weak acid. It's equilibrium of dissociation will be represented as follows.

          [tex]CH_{3}COOH(aq) + H_{2}O(l) \rightleftharpoons CH_{3}COO^{-}(aq) + H_{3}O^{+}(aq)[/tex]

On the other hand, sodium acetate ([tex]CH_{3}COONa[/tex]) is a salt of weak acid, that is, [tex]CH_{3}COOH[/tex] and strong base, that is, NaOH. Therefore, aqueous solution of sodium acetate will be basic in nature.

Since, acetic acid is a weak acid but still it is an acid. So, when methyl orange is added in a solution of acetic acid then it given a reddish-orange color because of its acidity.

When sodium acetate is mixed into this solution then it will dissociate as follows.

            [tex]CH_{3}COO^{-}Na^{+}(aq) \rightleftharpoons CH_{3}COO^{-}(aq) + Na^{+}(aq)[/tex]

As both solutions are liberating acetate ion upon dissociation. Hence, it is the common ion.

So, when more acetate ions will increase from dissociation of sodium acetate the according to Le Chatelier's principle the equilibrium will shift on left side.

As a result, there will be decrease in the concentration of hydronium ions. As a result, there will be increase in the pH of the system.

Hence, color of methyl orange will change from reddish orange to yellow. This shift in equilibrium is due to the common ion which is [tex]CH_{3}COO^{-}[/tex] ion.

Answer:

At high temperature the enzyme becomes denatured.

Lower temperature the enzymes become inactive.

Explanation:

Enzymes do not work at high temperature since the temperature kills the cells. And at LOW temperature enzymes have no energy to perform their work hence becomes inactive.

Substance X is the substrate for the initial enzyme in the metabolic pathway. The sequence represents a process known as feedback inhibition, where the end product (A) inhibits an enzyme early in the pathway, thus controlling the production rate.

In the provided sequence X → Y → Z → A, product A inhibits the enzyme that catalyzes the reaction converting X to Y. In this scenario, substance X is the substrate for the initial enzyme in this metabolic pathway. Enzymes, which are usually proteins, catalyze biochemical reactions by forming temporary and reversible complexes with their substrates at the enzyme's active site. They do this by lowering the activation energy for a chemical reaction to occur. Substrate X gets converted to Y, Y then converts to Z, and finally, Z gets converted to A.

This process is an example of feedback inhibition, a regulatory mechanism in cells. Feedback inhibition involves the end product of a metabolic pathway, in this case substance A, binding to an enzyme that acts early in the pathway (converting X into Y). This binding typically occurs at a position remote from the enzyme's active site (an allosteric site), and it inhibits the enzyme's activity, thereby reducing the speed of production when the levels of the end product (A) are high. This mechanism prevents the unnecessary accumulation of product A when it is already abundant.

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hey there!:

H2S(aq) <=> H⁺(aq) + HS⁻(aq)

K'c = [H⁺][HS⁻]/[H₂S] = 9.5*10⁻⁸

HS⁻(aq) <=> H⁺(aq) + S²⁻(aq)

K"c = [H⁺][S²⁻]/[HS⁻] = 1.0*10⁻¹⁹

H₂S(aq) <=> 2 H⁺(aq) + S²⁻(aq)

Kc = [H⁺]²[S²⁻] / [H₂S]

= [H+][HS⁻] / [H₂S] * [H⁺][S²⁻]/[HS⁻]

= K'c *K"c

= ( 9.5*10⁻⁸ ) * ( 1.0 x 10⁻¹⁹ )

= 9.5*10⁻²⁷

Hope this helps!

The equilibrium constants the following reaction at the same temperature is 9.5*10⁻²⁷.

Equilibrium is the state that is in control, a balance state in which no changes occur.

The calculation of equilibrium constants is

[tex]H_2S(aq) < = > H^+(aq) + HS^-(aq)[/tex]

K'c = [H⁺] [HS⁻] / [H₂S] = 9.5 * 10⁻⁸

HS⁻ (aq) <=> H⁺(aq) + S²⁻(aq)

K"c = [H⁺] [S²⁻]/[HS⁻] = 1.0 * 10⁻¹⁹

H₂S (aq) <=> 2 H⁺(aq) + S²⁻(aq)

Kc = [H⁺]²[S²⁻] / [H₂S]

= [H+] [HS⁻] / [H₂S] * [H⁺] [S²⁻] / [HS⁻]

= K'c *K"c

= ( 9.5*10⁻⁸ ) * ( 1.0 x 10⁻¹⁹ )

= 9.5*10⁻²⁷

Thus, the equilibrium constants of the following reaction at the same temperature is 9.5*10⁻²⁷.

Learn more about equilibrium

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Answer:

B. Carbon dioxide

Explanation:

A catalytic converter is designed and placed in the exhaust of most automobiles to remove harmful gases from escaping into the environment.

The converter uses palladium and platinum which are both catalyst to reduce harmful gases such as nitrogen oxide which causes acid rain, carbon monoxide which affects human haemoglobin and other hydrocarbons into less harmful ones.  

The catalytic converter helps to convert carbon monoxide, a product of incomplete combustion of hydrocarbons into less harmful carbondioxde. Carbon monoxide is a very toxic gas. It causes harm to both plants and animals as well.

Final answer:

Intensive properties are constant regardless of the amount of substance, while extensive properties depend on the amount. Temperature and density are examples of intensive properties, whereas mass and volume are extensive properties.

Explanation:

The difference between an intensive property and an extensive property is fundamental in chemistry and relates to how properties of matter are defined in relation to the amount of substance present. Extensive properties are those that depend on the amount of matter, such as mass and volume. For instance, a larger amount of substance will have a greater mass and volume than a smaller amount. In contrast, intensive properties do not depend on the amount of matter. These properties, such as temperature and density, remain consistent regardless of how much substance you have.

For example, whether you have a gallon or a cup of milk at 20 °C, the temperature is the same because temperature is an intensive property. Similarly, the density of a material is an intensive property because it is defined as the mass per unit volume, a ratio of two extensive properties which effectively 'cancels out' the dependence on quantity.

Answer: Yes

Explanation:

Limiting reagent is the reagent which limits the formation of product as it gets completely consumed in the reaction.

Excess reagent is the reagent which is left unreacted in the reaction.

For example:  [tex]2HCl+Ca\rightarrow CaCl_2+H_2[/tex]

If there are 2 moles of [tex]HCl[/tex] and 2 moles of [tex]Ca[/tex]

As can be seen from the chemical equation,

2 moles of hydrochloric acid react with 1 mole of calcium.

Thus 2 moles of [tex]HCl[/tex] will completely react with 1 mole of calcium and (2-1)=1 mole of calcium will remain as such.

Thus HCl is the limiting reagent as it limits the formation of product and calcium is the excess reagent as it is left unreacted.

Final answer:

The limiting reactant is the reactant that determines the amount of product that can be formed in a chemical reaction. It is completely consumed in the reaction.

Explanation:

The limiting reactant (or limiting reagent) is the reactant that determines the amount of product that can be formed in a chemical reaction. The reaction proceeds until the limiting reactant is completely used up. The other reactant or reactants are considered to be in excess. To determine the limiting reactant, you need to compare the amount of each reactant present in the reaction to the stoichiometric ratios in the balanced chemical equation. The reactant with the smallest amount is the limiting reactant.

Answer: a) 18.3 grams

b) [tex]CaCO_3[/tex] is the excess reagent and 16.5g of [tex]CaCO_3[/tex] will remain after the reaction is complete.

Explanation:

[tex]CaCO_3+2HCl\rightarrow CaCl_2+H_2O+CO_2[/tex]

[tex]\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}[/tex]

[tex]\text{Number of moles of calcium carbonate}=\frac{26g}{100g/mol}=0.26moles[/tex]

[tex]\text{Number of moles of hydrochloric acid}=\frac{12g}{36.5g/mol}=0.33moles[/tex]

According to stoichiometry:

2 mole of [tex]HCl[/tex] react with 1 mole of [tex]CaCO_3[/tex]

0.33 moles of [tex]HCl[/tex] will react with=[tex]\frac{1}{2}\times 0.33=0.165moles[/tex] of [tex]CaCO_3[/tex]

Thus [tex]HCl[/tex] is the limiting reagent as it limits the formation of product and [tex]CaCO_3[/tex] is the excess reagent.

2 moles of [tex]HCl[/tex] produce = 1 mole of [tex]CaCl_2[/tex]

0.33 moles of [tex]HCl[/tex] produce=[tex]\frac{1}{2}\times 0.33=0.165moles[/tex] of [tex]CaCl_2[/tex]

Mass of [tex]CaCl_2=moles\times {\text{Molar Mass}}=0.165\times 111=18.3g[/tex]

As 0.165 moles of [tex]CaCO_3[/tex] are used and (0.33-0.165)=0.165 moles of [tex]CaCO_3[/tex] are left unused.

Mass of [tex]CaCO_3[/tex] left unreacted =[tex]moles\times {\text {Molar mass}}=0.165\times 100=16.5g[/tex]

Thus 18.3 g of [tex]CaCl_2[/tex] are produced. [tex]CaCO_3[/tex] is the excess reagent and 16.5g of [tex]CaCO_3[/tex] will remain after the reaction is complete.

Answer : The concentration of [tex]COF_2[/tex] remains at equilibrium will be, 0.37 M

Explanation :  Given,

Equilibrium constant = 4.90

Initial concentration of [tex]COF_2[/tex] = 2.00 M

The balanced equilibrium reaction is,

                       [tex]2COF_2(g)\rightleftharpoons CO_2(g)+CF_4(g)[/tex]

Initial conc.    2 M                 0             0

At eqm.         (2-2x) M          x M         x M

The expression of equilibrium constant for the reaction will be:

[tex]K_c=\frac{[CO_2][CF_4]}{[COF_2]^2}[/tex]

Now put all the values in this expression, we get :

[tex]4.90=\frac{(x)\times (x)}{(2-2x)^2}[/tex]

By solving the term 'x' by quadratic equation, we get two value of 'x'.

[tex]x=1.291M\text{ and }0.815M[/tex]

Now put the values of 'x' in concentration of [tex]COF_2[/tex] remains at equilibrium.

Concentration of [tex]COF_2[/tex] remains at equilibrium = [tex](2-2x)M=[2-2(1.219)]M=-0.582M[/tex]

Concentration of [tex]COF_2[/tex] remains at equilibrium = [tex](2-2x)M=[2-2(0.815)]M=0.37M[/tex]

From this we conclude that, the amount of substance can not be negative at equilibrium. So, the value of 'x' which is equal to 1.291 M is not considered.

Therefore, the concentration of [tex]COF_2[/tex] remains at equilibrium will be, 0.37 M

Answer:

The chef can be able to make 36 sandwiches.

Explanation:

3 slices of jalapeno cheddar cheese + 5 slices of honey ham → 1 sandwich

According to information, 3 slices of jalapeno cheddar cheese will combine with 5 slices of  honey ham to give 1 sandwich.

180 slices of jalapeno cheddar cheese will combine with:

[tex]\frac{5}{3}\times 180=300 [/tex] slices of honey ham

But we are having only 180 slices of honey ham. tghe number of sandwiches will depend upon number of slices of honey ham.

180 slices of honey ham will combine with:

[tex]\frac{3}{5}\times 180=108 [/tex] slices of jalapeno cheddar cheese

From 5 slices of honey ham we can make 1 sandwich,then from 180 slices of hinry ham we will be able make:

[tex]\frac{1}{5}\times 180=36 sandwiches[/tex]

The chef can be able to make 36 sandwiches.

Answer:

answer is 12.18

Explanation:

(C2H5NH2, Kb = 5.6 x 10-4.)

Answer:

pH = 10.1

Explanation:

For weak base solutions [OH] = SqrRt([Base]·Kb

Then, from pH + pOH = 14 => pH = 14 - pOH

[OH} = SqrRt[(0.22)(5.6 x 10⁻⁴)] = 3.91

pH = 14 - 3.91 = 10.1

Answer: False

Explanation:

Viscosity is defined as the resistance to the flow of a fluid. More are the inter molecular forces between the particles of a liquid, the more the viscosity of the liquid and thus it will flow slowly.

Example: Oil is more viscous than water and thus flows slowly than water.

Effect of temperature: Viscosity decreases with increase in temperature as the forces among particles decrease due to increase in kinetic energy and thus they offer less resistance to flow.

Thus viscosity of liquids will decrease with increasing temperature.

Hey there!:

Aqueous ethanol contains water , sodium borohydride will react with water and decompose to give hydrogen gas :

NHB4 + 2 H2O => NaBO2 + 4 H2

thus a large excess of borohydride should be used used to take into account losses from the reaction with water , so that there is sufficient sodium borohydride left for the reduction of the chemical compound os interest .

Hope this helps!

The importance of using a large excess of sodium borohydride in a reduction in aqueous ethanol lies in its role as a reducing agent that donates hydrogen ions. However, in an aqueous solution, some of the sodium borohydride may react with water in a hydrolysis reaction, forming hydrogen gas and borate ions. Using an excess ensures an ample amount for the intended reaction.

It's important to use a large excess of sodium borohydride when doing a reduction in aqueous ethanol because sodium borohydride (NaBH₄) is an excellent reducing agent. It donates hydrogen ions (H⁻) which do not survive in an acidic medium. The H⁻ ions react initially, and then the acid is added to donates a proton to oxygen (O) in the second step.

However, the aqueous environment complicates this process because water can react with sodium borohydride in a hydrolysis reaction. Water acts as an incoming nucleophile, and in the presence of water, NaBH4 may end up reducing water molecules, forming hydrogen gas (H₂) and borate ions (BO3⁻). Using an excess of sodium borohydride ensures that there's enough of it to react with the intended substance, even when a portion of it reacts with water.

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Answer : The mass of the water in two significant figures is, [tex]3.0\times 10^1g[/tex]

Explanation :

In this case the heat given by the hot body is equal to the heat taken by the cold body.

[tex]q_1=-q_2[/tex]

[tex]m_1\times c_1\times (T_f-T_1)=-m_2\times c_2\times (T_f-T_2)[/tex]

where,

[tex]c_1[/tex] = specific heat of iron metal = [tex]0.45J/g^oC[/tex]

[tex]c_2[/tex] = specific heat of water = [tex]4.18J/g^oC[/tex]

[tex]m_1[/tex] = mass of iron metal = 32.3 g

[tex]m_2[/tex] = mass of water = ?

[tex]T_f[/tex] = final temperature of mixture = [tex]59.2^oC[/tex]

[tex]T_1[/tex] = initial temperature of iron metal = [tex]21.9^oC[/tex]

[tex]T_2[/tex] = initial temperature of water = [tex]63.5^oC[/tex]

Now put all the given values in the above formula, we get

[tex]32.3g\times 0.45J/g^oC\times (59.2-21.9)^oC=-m_2\times 4.18J/g^oC\times (59.2-63.5)^oC[/tex]

[tex]m_2=30.16g\approx 3.0\times 10^1g[/tex]

Therefore, the mass of the water in two significant figures is, [tex]3.0\times 10^1g[/tex]

The mass of the water in the insulated container is 30.04 g

Heat loss = Heat gain

MᵥᵥC(Tᵥᵥ – Tₑ) = MᵢC(Tₑ – Mᵢ)

Mᵥᵥ × 4.184 (63.5 – 59.2) = 32.2 × 0.45(59.2 – 21.9)

Mᵥᵥ × 4.184(4.3) = 14.49(37.3)

Clear bracket

Mᵥᵥ × 17.9912 = 540.477

Divide both side by 17.9912

Mᵥᵥ = 540.477 / 17.9912

Mᵥᵥ = 30.04 g

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First we need to calculate the number of moles of NaOH titrated.

molar concentration = number of moles / solution volume (liter)

number of moles = molar concentration × solution volume

number of moles of NaOH = 1.5 × 0.0075 = 0.01125 moles

Then we look at the chemical reaction:

CH[tex]_{3}[/tex]-COOH +  NaOH = CH[tex]_{3}[/tex]COONa + H[tex]_{2}[/tex]O

We can see that 1 mole of acetic acid is reacting with one mole of sodium hydroxide. Then we can conclude that 0.01125 moles of sodium hydroxide reacts with 0.01125 moles of acetic acid.

Now we can get the mass of acetic acid:

number of moles = mass (grams) / molecular mass (g/mol)

mass = number of moles × molecular mass

mass of acetic acid = 0,01125 × 60 = 0.675 g

We assume that the density of the vinegar = 1 g/mL, so the mass percent of acetic acid is:

concentration of acetic acid = (mass of acetic acid / mass of vinegar) × 100

concentration of acetic acid = (0.674 / 7) ×  100 = 9.6 %

The mass percent of acetic acid in the vinegar sample 9.6 %.

The reaction will be,

[tex]\rm \bold { CH_3-COOH + NaOH \leftrightharpoons CH_3COONa + H_2O}[/tex]

Means 1 mole  acetic acid is reacting with one mole of sodium hydroxide.

Number of moles of NaOH titrated,

Number of moles of  [tex]\rm \bold{ NaOH = 1.5 \times 0.0075 = 0.01125 moles}[/tex]

number of moles of [tex]\rm \bold { CH_3COOH}[/tex]  = 0.01125 moles

Mass of [tex]\rm \bold { CH_3COOH}[/tex]  = [tex]\rm \bold{ 0.01125 \times 60 = 0.675 g}[/tex]

Assume that the density of the vinegar is  1 g/mL

The mass percent of acetic acid can be calculated,

The mass percent of acetic acid = (mass of acetic acid / mass of vinegar) 100

The mass percent of acetic acid = [tex]\rm \bold{\frac{0.674}{7} \times 100 = 9.6 } \\[/tex]

Hence, we can conclude that  the mass percent of acetic acid in the vinegar sample 9.6 %.

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hey there!:

In the case of ammonia, the hydrogen bond is formed using the lone pair present in nitrogen and the hydrogen having δ+ charge (due to bonding with electronegative N) of another ammonia molecule. Thus the inter molecular attraction increases which in turn increases the boiling point .

Option B is the correct answer.

Hope this helps!

The intermolecular force or bond which  is responsible for the high boiling point of NH₃ relative to PH₃ and AsH₃ is covalent bonding.

Covalent bonding is defined as a type of bonding which is formed by the mutual sharing of electrons to form electron pairs between the two atoms.These electron pairs are called as bonding pairs or shared pair of electrons.

Due to the sharing of valence electrons , the atoms are able to achieve a stable electronic configuration . Covalent bonding involves many types of interactions like σ bonding,π bonding ,metal-to-metal bonding ,etc.

Sigma bonds are the strongest covalent bonds while the pi bonds are weaker covalent bonds .Covalent bonds are affected by electronegativities of the atoms present in the molecules.Compounds having covalent bonds have lower melting points as compared to those with ionic bonds.

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Answer : The answer in standard form is, 0.00318 mg.

Explanation :

Significant figures : The figures in a number which express the value -the magnitude of a quantity to a specific degree of accuracy is known as significant digits.

The rule apply for the addition and subtraction is :

The least precise number present after the decimal point determines the number of significant figures in the answer.

As we are given :

[tex](3.26\times10^{-3})mg-(7.88\times 10^{-5})mg[/tex]

First we have to convert scientific notation into standard form.

[tex]\Rightarrow 0.00326mg-0.0000788mg[/tex]

[tex]\Rightarrow 0.00318mg[/tex]

As per rule, the least precise number present after the decimal point is 5. So, the answer will be, 0.00318 mg.

Answer : The DePriester K-value for the species in the mixture is, 0.4

Explanation :

According to the Dalton's Law, the partial pressure exerted by component 'i' in a gas mixture is equal to the product of the mole fraction of the component and the total pressure.

[tex]p_i=X_i\times p[/tex]   ........(1)

According to the Raoult's law, the partial pressure exerted in gas phase by a component  is equal to the product of the vapor pressure of that component and its mole fraction for an ideal liquid solution.

[tex]p_i=Y_i\times p_v[/tex]   ........(2)

When the gas and the liquid are in equilibrium then these partial pressures must be the same.

[tex]X_i\times p=Y_i\times p_v[/tex]

or,

[tex]\frac{X_i}{Y_i}=\frac{p_v}{p}[/tex]

This ration is called as equilibrium ratio [tex]K_i[/tex] of the i-th component.

[tex]K_i=\frac{X_i}{Y_i}=\frac{p_v}{p}[/tex]    .......(3)

As we are given that,

Total pressure = [tex]p=50psia[/tex]

The vapor pressure = [tex]p_v=20psia[/tex]

According to the relation (3), we get

[tex]K_i=\frac{X_i}{Y_i}=\frac{p_v}{p}=\frac{20}{50}=0.4[/tex]

Therefore, the DePriester K-value for the species in the mixture is, 0.4

Final answer:

To calculate the equilibrium concentrations of reactants and product, we need to use the given equilibrium constant, Kc, and the initial concentrations of the reactants.

Explanation:

To calculate the equilibrium concentrations of reactants and product, we need to use the given equilibrium constant, Kc, and the initial concentrations of the reactants. The balanced equation for the reaction is CH4 (g) + CCl4 (g) ⇌ 2 CH2Cl2 (g).

First, calculate the initial moles of each reactant by multiplying the initial concentration by the volume of the vessel. Then, we can set up an ICE (Initial-Change-Equilibrium) table to find the change in concentration of each species and the equilibrium concentrations.

Using the ICE table and the equilibrium constant expression, we can solve for the equilibrium concentrations of CH4, CCl4, and CH2Cl2.

Answer:The molecular formula of the oxide of metal be [tex]X_2O_3[/tex]. The balanced equation for the reaction is given by:

[tex]X_2O_3+3CO\rightarrow 3CO_2+2X[/tex]

Explanation:

Let the molecular formula of the oxide of metal be [tex]X_2O_y[/tex]

[tex]X_2O_y+yCO\rightarrrow yCO_2+2X[/tex]

Mass of metal product = 1.68 g

Moles of metal X =[tex]\frac{1.68 g}{55.9 g/mol}=0.03005 mol[/tex]

1 mol of metal oxide produces 2 moles of metal X.

Then 0.03005 moles of metal X will be produced by:

[tex]\frac{1}{2}\times 0.03005 mol=0.01502 mol[/tex] of metal oxide

Mass of 0.01502 mol of metal oxide = 2.40 g (given)

[tex]0.01502 mol\times (2\times 55.9 g/mol+y\times 16 g/mol)=2.40 g[/tex]

y = 2.999 ≈ 3

The molecular formula of the oxide of metal be [tex]X_2O_3[/tex]. The balanced equation for the reaction is given by:

[tex]X_2O_3+3CO\rightarrow 3CO_2+2X[/tex]

Final answer:

To show the simplest formula of the oxide is X2O3, we calculate the moles of metal (X) and oxygen from given masses, find their ratio, and deduce the empirical formula. The balanced equation for the reaction with carbon monoxide is X2O3(s) + 3CO(g) → 2X(s) + 3CO2(g).

Explanation:

To prove that the simplest formula of the oxide is X2O3, first we need to calculate the moles of metal X produced. Since the molar mass of X is given as 55.9 g/mol, we divide the mass of metal product (1.68 g) by the molar mass of X to obtain the number of moles:

moles of X = 1.68 g / 55.9 g/mol = 0.03005 mol

We know that the initial mass of the oxide is 2.40 g and the product (X) is 1.68 g, so the mass of oxygen in the oxide is:

mass of O = 2.40 g - 1.68 g = 0.72 g

rationalizing the ratio, we get approximately 2:3

Thus, the empirical formula of the oxide is X2O3.

Balanced Equation for the Reaction

The balanced equation for the reaction of metal X's oxide with carbon monoxide to obtain metal X and carbon dioxide is:

X2O3(s) + 3CO(g) → 2X(s) + 3CO2(g)

This equation shows that the oxide of metal X reacts with carbon monoxide in a 1:3 mole ratio to produce the pure metal and carbon dioxide in a 2:3 mole ratio.

Hey there!:

Henry law solubility proportional to partial pressure of gas over a solvent  :

for pressure of 1 atm s = 0.034

fro partial pressure of =0 .0003

Therefore :

Solubility = 0.0003 / 1 * 0.034

Solubility = 1.02 * 10⁻⁵ mol/L

Hope this helps!

Answer:

Explanation:

From Henry's law

c = kP

where

c = molar concentration

k = proportionality constant

P = pressure

Hence, solubility in water

[tex]k = \frac{c}{P}\\\\k = \frac{0.34}{1}\\\\k = 0.034mol/L-atm[/tex]

The solubility of [tex]CO_2[/tex] under atmospheric conditions in air is

[tex]c = kP\\\\c = 0.034 * 0.0003\\\\c = 1.02*10^{-5} mol/L[/tex]

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Answer:

The concentration of the solution, [tex]C=7.2992\times 10^{-6} M[/tex]

Explanation:

The absorbance of a solution can be calculated by Beer-Lambert's law as:

[tex]A=\varepsilon Cl[/tex]

Where,  

A is the absorbance  of the solution

ɛ is the molar absorption coefficient ([tex]L.mol^{-1}.cm^{-1}[/tex])

C is the concentration ([tex]mol^{-1}.L^{-1}[/tex])

l is the path length of the cell in which sample is taken (cm)

Given,

A = 0.20

ɛ = 27400 [tex]M^{-1}.cm^{-1}[/tex]

l = 1 cm

Applying in the above formula for the calculation of concentration as:

[tex]A=\varepsilon Cl[/tex]

[tex]0.20= 27400\times C\times 1[/tex]

[tex]C = \frac{0.20}{27400\times 1} M[/tex]

So , concentration is:

[tex]C=7.2992\times 10^{-6} M[/tex]

The concentration of the yellow dye solution as obtained is 7.29 × 10-⁶M.

BEER-LAMBERT EQUATION:

A = εbc

Where;

c = A ÷ εb

c = A ÷ εb

c = 0.20 ÷ (27400 × 1)

c = 0.20 ÷ 27400

c = 7.29 × 10-⁶M

Therefore, the concentration of the yellow dye solution as obtained is 7.29 × 10-⁶M.

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Answer:

Explanation:

0 degrees kelvin is mighty cold. It should be 0 degrees Celsius.

The answer is false.

Answer:

18.700 g

Explanation:

As the urea is a nonvolatile and nonelectrolyte solute, it will reduce the vapor pressure of the solution according to:

[tex]P_{vs} =P_{w} *x_{w}[/tex]

Where [tex]P_{vs}[/tex] is the vapor pressure of the solution, [tex]P_{w}[/tex] is the vapor pressure of the pure water, and [tex]x_{w}[/tex] is the molar fraction of water. This equation applies just for that kind of solutes and at low pressures (23.76 mmHg is a low pressure).

From the equation above lets calculate the water molar fraction:

[tex]23.22mmHg=23.76mmHg*x_{w}\\ x_{w}=\frac{23.22mmHg}{23.76mmHg}=0.977[/tex]

So, the molar fraction of the urea should be: [tex]x_{urea}=1-x_{w}=0.023[/tex]

Then, calculate the average molecular weight:

[tex]M=x_{w}*MW_{w}+x_{urea}*MW_{urea}\\ M=0.977*18.02+0.023*60.10=18.989[/tex]

The molar fraction of urea is:

[tex]0.023=\frac{X urea mol}{S solution moles}=\frac{x urea grams}{238.2+x (solution grams)}*\frac{1 urea mol}{60.10 g}*\frac{18.989 solution grams}{1 solution mol}[/tex]

Solving for x,

[tex]x=18.700g[/tex]