Your boss tells you that water at 68 F is flowing in a cooling tower loop at a rate of 600 gpm, in an 8-inch inside diameter pipe. Your boss asks you whether this flow is the laminar or turbulent flow regime. Calculate the Reynolds number and state whether the flow is laminar or turbulent.

Answer: The correct answer is Option  d.

Explanation:

To calculate the molarity of base, we use the equation given by neutralization reaction:

[tex]n_1M_1V_1=n_2M_2V_2[/tex]

where,

[tex]n_1,M_1\text{ and }V_1[/tex] are the n-factor, molarity and volume of acid which is [tex]H_2SO_4[/tex]

[tex]n_2,M_2\text{ and }V_2[/tex] are the n-factor, molarity and volume of base which is KOH

We are given:

[tex]n_1=2\\M_1=0.543M\\V_1=72.1mL\\n_2=1\\M_2=?M\\V_2=39.0mL[/tex]

Putting values in above equation, we get:

[tex]2\times 0.543\times 72.1=1\times M_2\times 39.0\\\\M_2=2.01M[/tex]

Hence, the correct answer is Option d.

The concentration of the base is 2.01 M

A neutralization reaction is a reaction that occurs between an acid and a base to yield salt and water only;

This reaction occurs as follows; H2SO4 + 2KOH ----->K2SO4 + H2O

From the titration formula;

concentration of acid CA =  0.543 M

volume of acid VA = 72.1 mL

concentration of baseCB = ?

volume of base VB= 39.0 mL

Number of moles of acid = 1

Number of moles of base = 2

Given that;

CAVA/CBVB = NA/NB

CAVANB = CBVBNA

CB = 0.543 M * 72.1 mL * 2/39.0 mL * 1

CB = 2.01 M

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Answer:

8 drops of 1.00 M NaOH will be needed.

Explanation:

Concentration of [tex][OH^-][/tex] in bleach solution = 0.02 M

[tex]NaOH\rightarrow OH^-+Na^+[/tex]

[tex]NaOH=[OH^-]=0.02M[/tex]

Concentration of bleach solution we want ,[tex]M_1[/tex] = 0.02 M

Volume of the bleach solution,[tex]V_1[/tex] = 20 ml

Concentration of NaOH solution,[tex]M_2[/tex] = 1.00 M

Volume of the NaOH solution required ,[tex]V_2[/tex] = ?

[tex]M_1V_1=M_2V_2[/tex]

[tex]0.02 M\times 20 mL=1.00 M\times V_2[/tex]

[tex]V_2=\frac{0.02 M\times 20 mL}{1.00 M}=0.4 mL[/tex]

1 mL = 20 drops

0.4 mL = 0.4 × 20 drops = 8 drops

8 drops of 1.00 M NaOH will be needed.

Answer:

0.971 grams

Explanation:

Given:

Temperature = 3.0° C = 3 + 273 = 276 K

Volume, V = 5.0 L

Pressure, P = 0.100 atm

Now, from the relation

PV = nRT

where,

n is the number of moles,

R is the ideal gas constant  = 0.082057 L atm/mol.K

thus,

0.1 × 5 = n ×  0.082057 × 276

or

n = 0.022 moles

Also,

Molar mass of the Dinitrogen monoxide gas (N₂O)

= 2 × Molar mass of nitrogen + 1 × Molar mass of oxygen

= 2 × 14 + 16 = 44 grams/mol

Therefore, Mass of 0.022 moles of N₂O = 0.022 × 44 = 0.971 grams

Answer:

-0.93 °C

Explanation:

Hello,

The freezing-point depression is given by:

[tex]T_f-T_f^*=-iK_{solvent}m_{solute}[/tex]

Whereas [tex]T_f[/tex] is the freezing temperature of the solution, [tex]T_f^*[/tex] is the freezing temperature of the pure solvent (0 °C since it is water), [tex]i[/tex] the Van't Hoff factor (1 since the solute is covalent), [tex]K_{f,solvent}[/tex] the solvent's freezing point depression point constant (in this case [tex]1.86 C\frac{kg}{mol}[/tex]) and [tex]m_{solute}[/tex] the molality of the glucose.

As long as the unknown is [tex]T_f[/tex], solving for it:

[tex]T_f=T_f^*-iK_fm\\T_f=0C-1*1.86C\frac{kg}{mol}*0.5\frac{mol}{kg}  \\T_f=-0.93C[/tex]

Best regards.

Answer: The volume of solution is [tex]8.03\times 10^5mL[/tex]

Explanation:

The relationship between specific gravity and density of a substance is given as:

[tex]\text{Specific gravity}=\frac{\text{Density of a substance}}{\text{Density of water}}[/tex]

Specific gravity of sulfuric acid solution = 1.22

Density of water = 1.00 g/mL

Putting values in above equation we get:

[tex]1.22=\frac{\text{Density of sulfuric acid solution}}{1.00g/mL}\\\\\text{Density of sulfuric acid solution}=(1.22\times 1.00g/mL)=1.22g/mL[/tex]

We are given:

25% (m/m) sulfuric acid solution. This means that 25 g of sulfuric acid is present in 100 g of solution

Conversion factor:  1 kg = 1000 g

Mass of solution having 254 kg or 245000 g of sulfuric acid is calculated by using unitary method:

If 25 grams of sulfuric acid is present in 100 g of solution.

So, 245000 grams of sulfuric acid will be present in = [tex]\frac{100}{25}\times 245000=980000g[/tex]

To calculate volume of a substance, we use the equation:

[tex]\text{Density of substance}=\frac{\text{Mass of substance}}{\text{Volume of substance}}[/tex]

Density of solution = 1.22 g/mL

Mass of Solution = 980000 g

Putting values in above equation, we get:

[tex]1.22g/mL=\frac{980000g}{\text{Volume of solution}}\\\\\text{Volume of solution}=\frac{980000g}{1.22g/mL}=8.03\times 10^5mL[/tex]

Hence, the volume of solution is [tex]8.03\times 10^5mL[/tex]

Answer:

691.84g

Explanation:

I'm assuming that by CzHg, you mean C3H2

First, use the mole ratio in the equation to find the moles of CO2

n (CO2)= n ( C3H2) × 3

= 5.24 × 3

= 15.72

To find the mass of CO2 produced in grams, complete the following calculation

m= n × MM

where

m = mass

n= moles

MM= molecular mass

m= 15.72 × (12.01 +( 16×2))

m =691.8372

m= 691.84g

Explanation:

It is known that for [tex]NO_{2}[/tex], ppm present in 1 [tex]mg/m^{3}[/tex] are as follows.

                      1 [tex]\frac{mg}{m^{3}}[/tex] = 0.494 ppm

So, 150 [tex]pg/m^{3}[/tex] = [tex]\frac{150}{1000} mg/m^{3}[/tex]

                       = 0.15 [tex]mg/m^{3}[/tex]

Therefore, calculate the equivalent concentration in ppm as follows.

             [tex]0.15 \times 0.494 ppm[/tex]

              = 0.074 ppm

Thus, we can conclude that the equivalent concentration in ppm at STP is 0.074 ppm.  

Answer:

b) Counter current

Explanation:

In mechanical, chemical, nuclear and other systems, it happens that heat must be transferred from one place to another or from one fluid to another. Heat exchangers are the devices that allow you to perform this task  the types of exchangers are presented  of heat as a function of flow: parallel flow; counterflow; cross flow.

Among the main reasons why exchangers are used

Heat are as follows:

• Heat a cold fluid using a fluid with a higher temperature.

• Reduce the temperature of a fluid by means of a fluid with a lower temperature.

• Bring the fluid to the boiling point using a fluid with a higher temperature.

• Condense a fluid in a gaseous state by means of a cold fluid

A backflow occurs when the two fluids flow in the same direction but in  opposite way. Each of the fluids enters the exchanger through different ends Since the fluid with less  temperature goes backflow from the heat exchanger at the end where the fluid enters with higher temperature,  the temperature of the coldest fluid will approach the temperature of the inlet fluid.

This type of exchanger  turns out to be more efficient than the other two types mentioned above. In contract with the exchanger  parallel flow heat, the counterflow exchanger may have the highest temperature in the cold fluid and the  lower temperature in the hot fluid after heat transfer in the exchanger.

Be careful with turbulent that it is not a type of exchanger but a system in which a fluid is found.

Answer:

50 mL

Explanation:

Explanation:

Aldonic Acid:

Aldonic acids are suger acids.

General formula of aldonic acid = [tex]HOOC-(CHOH)_n-CH_2OH[/tex]

Aldonic acids are obtained by the oxidation of aldehydic group of suger.

So, aldonic acids have hydroxyl group at one terminal and carboxylic group at another terminal.

Gluconic acid is an example of aldonic acid.

Uronic Acid:

It is also a type of suger acid having carbonyl functional group at one terminal and carboxylic group at other terminal.

It is obtained by oxidation of hydroxyl group of the sugar.

Aldaric Acid:

Aldaric acid is also a type of sugar acid having carboxylic acid functional group at both the ends.

Both the hydroxyl group and aldehydic group are oxidized to form class of compound, called aldaric acid.

Answer:

a.

P = 3 , N = 4

b.

P = 8 , N = 8

c.

P = 90 , N = 142

d.

P = 94 , N = 145

Explanation:

Mass number  = Number of protons + Number of neutrons

Also,

Atomic number = Number of protons

Li - 7

Given, Mass number of Lithium = 7

For lithium, atomic number = 3

So,

Number of protons = 3

Number of neutrons = Mass number - Number of protons = 7 - 3 = 4

O - 16

Given, Mass number of oxygen = 16

For oxygen, atomic number = 8

So,

Number of protons = 8

Number of neutrons = Mass number - Number of protons = 16 - 8 = 8

Th - 232

Given, Mass number of Thorium = 232

For Thorium, atomic number = 90

So,

Number of protons = 90

Number of neutrons = Mass number - Number of protons = 232 - 90 = 142

Pu - 239

Given, Mass number of Plutonium = 239

For Plutonium, atomic number = 94

So,

Number of protons = 94

Number of neutrons = Mass number - Number of protons = 239 - 94 = 145

Answer: 1. The molecular weight of the compound is 222.8 g/mol

2. The probable molecular formula of the solute is [tex]InCl_3[/tex]

Explanation:

Elevation in boiling point is given by:

[tex]\Delta T_b=i\times K_f\times m[/tex]

[tex]\Delta T_b=T_b-T_b^0=(116.3-114.1)^0C=2.2^0C[/tex] = elevation in boiling point

i= vant hoff factor = 1 (for non electrolyte)

[tex]K_b[/tex] = boiling point constant = [tex]9.43^0Ckg/mol[/tex]

m= molality

[tex]\Delta T_b=i\times K_b\times \frac{\text{mass of solute}}{\text{molar mass of solute}\times \text{weight of solvent in kg}}[/tex]

Weight of solvent (tin chloride)= 50.0 g =0.05 kg

Molar mass of unknown solute = M g/mol

Mass of unknown solute = 2.6 g

[tex]2.2=1\times 9.43\times \frac{2.6g}{M g/mol\times 0.05kg}[/tex]

[tex]M=222.8g/mol[/tex]

The possible formula for the compound would be [tex]InCl_3[/tex] as indium has valency of 3 and chlorine has valency of 1 has molecular mass almost equal to 222.8.

Answer:

Maximum number of bonds each of the elements can form:

C: 4 bonds, H: 1 bonds, O: 2 bonds, N: 3 bonds, B: 3 bonds, S: 4 bonds.

Explanation:

The elements C, O, S and N follows the octet rule which establishes that every atom must have eight valence electrons to be stable. Thus, Carbon has 4 valence electrons, so could link 4 atoms. Nitrogen has 5 valence electrons, so could link 3 atoms. Oxygen and Sulfur have 6 valence electrons, so could link 2 atoms. Hydrogen and Boron are exceptions to the octet rule, therefore, the first one only needs 2 valence electron to be stable and the second one only needs 6 valence electron to be stable.

Final answer:

The number of covalent bonds an element can form generally corresponds with its group on the periodic table and its need to complete an octet, except for hydrogen which needs only two electrons. Group 4A elements like carbon form four bonds, Group 5A like nitrogen three, and Group 6A like oxygen and sulfur two. Boron typically forms three bonds but can form compounds or ions to achieve stability.

Explanation:

The number of covalent bonds an element can form is often related to its group number on the periodic table and its need to complete an octet of valence electrons. For example:

Carbon (C) is in group 4A, has four valence electrons, and tends to form four covalent bonds.

Hydrogen (H) needs two electrons for a full outer shell, so it forms one covalent bond.

Oxygen (O) is in group 6A with six valence electrons and forms two covalent bonds.

Nitrogen (N) is in group 5A, has five valence electrons, and forms three covalent bonds.

Boron (B) usually forms three covalent bonds, leaving it with six valence electrons.

Sulfur (S) is able to form two covalent bonds like oxygen, due to its position in group 6A.

Elements such as boron are unique in their bonding behaviors, often forming compounds or ions in order to achieve a more stable configuration, such as in the borohydride anion (BH4-). Transition elements and inner transition elements, with their d and f electrons, don't always follow the octet rule and can have variable bonding capacities.

Answer:

The correct option is: A. H₂SO₄

Explanation:

Acid is a charged or a neutral molecule that is a proton donor and electron pair acceptors.

Acids can be classified into monoprotic acids and polyprotic acids.

Monoprotic acids are the acids that can release only one proton on dissociation.

Whereas, polyprotic acids are the acids that can release more than one proton on dissociation.

Diprotic acid is a type of polyprotic acid that can release two protons on dissociation. Example: H₂SO₄

A diprotic acid is an acid that contains two ionizable hydrogen atoms per molecule. Among the provided options, H2SO4 or sulfuric acid is such a diprotic acid. It ionizes in two stages, forming sulfates and hydrogen sulfates.

The question asks about which of the given substances is a diprotic acid. Diprotic acids are those that contain two ionizable hydrogen atoms per molecule, which can release two protons or hydrogen ions. The ionization (release of protons) occurs in two steps: the first ionization generally takes place to a greater extent than the second.

By examining the chemical formulas of the options provided, we can identify H2SO4 (Sulfuric acid) as a diprotic acid. The ionization process works as following:

A significant attribute of diprotic acids like sulfuric acid is that they form both sulfates (e.g., Na2SO4) and hydrogen sulfates (e.g., NaHSO4).

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Explanation:

It is given that diameter of the pipe is 10 cm which is also equal to [tex]10 \times 10^{-2}m[/tex].

Velocity of water = 5 m/s

(a)   Formula to calculate volumetric flow rate is as follows.

                       Q = Area of the pipe (A) × Velocity of water (V)

                           = [tex]\frac{\pi}{4} \times 10 \times 10^{-2} \times 5 m^{3}/sec[/tex]

                           = 0.039 [/tex]m^{3}/sec[/tex]

                           = [tex]\frac{0.039 m^{3}/sec \times 60 sec}{1 min}[/tex]

                           = 2.36 [tex]m^{3} min^{-1}[/tex]

Hence, the volumetric flow rate is 2.36 [tex]m^{3} min^{-1}[/tex].

(b)    Formula to calculate mass flow rate is as follows.

                      [tex]Q \times \rho[/tex]

                     = [tex]2.36 m^{3} min^{-1} \times 1000 kg m^{-3}[/tex]

                     = 2356.19 kg/min

Therefore, the mass flow rate is 2356.19 kg/min.

Answer: The mass of proton is [tex]1.67\times 10^{-33}Gg[/tex]

Explanation:

Proton is one of the sub-atomic particle which is present in the nucleus of the atom.

We know that:

Mass of proton = [tex]1.67\times 10^{-27}kg[/tex]

To convert this into Giga grams, we use the conversion factor:

[tex]1Gg=1\times 10^6kg[/tex]

Converting the given value into Giga grams, we get:

[tex]\Rightarrow 1.67\times 10^{-27}kg\times \frac{1Gg}{1\times 10^6kg}=1.67\times 10^{-33}Gg[/tex]

Hence, the mass of proton is [tex]1.67\times 10^{-33}Gg[/tex]

Answer:

The air density in at points 1 is [tex]60.7 kg/m^3[/tex] and 2 is [tex]2060 kg/m^3[/tex].

Explanation:

Average molecular weight of an air ,M= 28.97 g/mol

[tex]PV=nRT[/tex]

or [tex] PM=dRT[/tex]

P = Pressure of the gas

n = moles of gas

T = Temperature of the gas

d = Density of the gas

M = molar mass of the gas

R = universal gas constant

Density at point-1 = [tex]d_1[/tex]

[tex]P_1 = 10,000 Pa=0.0986 atm[/tex]

[tex]1 Pa=9.86923\times 10^{-6} atm[/tex]

[tex]T_1 = 300^oC = 573.15 K[/tex]

M = 28.97 g/mol

[tex]d_1=\frac{PM}{RT}=\frac{0.0986 atm\times 28.97 g/mol}{0.0821 atm L/ mol K\times 573.15 K}[/tex]

[tex]d_1 =0.0607 g/ml[/tex]

1 g = 0.001 kg

[tex]1 mL = 10^{-6} m^3[/tex]

[tex]d_1=\frac{0.0607\times 0.001 kg}{10^{-6} m^3}=60.7 kg/m^3[/tex]

Density at point-2 = [tex]d_2[/tex]

[tex]P_2 = 575,000 Pa=5.67 atm[/tex]

[tex]T_2 = 700^oC = 973.15 K[/tex]

M = 28.97 g/mol

[tex]d_2=\frac{PM}{RT}=\frac{5.67 atm\times 28.97 g/mol}{0.0821 atm L/ mol K\times 973.15 K}[/tex]

[tex]d_2 =2.06 g/ml=2060 kg/m^3[/tex]

Answer: The number of electrons for n = 0, 1 and 2 are 2, 6 and 10 respectively.

Explanation:

Huckel's rule is used to determine the aromaticity in a compound. The number of delocalized [tex]\pi-[/tex] electrons are calculated by using the equation:

[tex]\text{Number of delocalized }\pi-\text{ electrons}=4n+2[/tex]

where,

n = 0 or any whole number

Putting values in above equation, we get:

[tex]\text{Number of delocalized }\pi-\text{ electrons}=4(0)+2=2[/tex]

Putting values in above equation, we get:

[tex]\text{Number of delocalized }\pi-\text{ electrons}=4(1)+2=6[/tex]

Putting values in above equation, we get:

[tex]\text{Number of delocalized }\pi-\text{ electrons}=4(2)+2=10[/tex]

Hence, the number of electrons for n = 0, 1 and 2 are 2, 6 and 10 respectively.

Answer:

Quantum mechanical atomic model.

Explanation:

The first model of electronic configuration was given by Bohr's model.

The most accurate model of electronic configuration is the quantum mechanical atomic model.

Bohr's model has various limitations:

1. It does not explain the Zeeman effect and stark effect.

2. It is not valid for multi-electron system.

3. Heisenberg uncertainty principle is not followed by this model

The quantum mechanical atomic model explains all the four quantum numbers for the electronic configuration of an atom in the periodic table.

The quantum mechanical atomic model considered the Heisenberg uncertainty principle.

Answer:

Quantum mechanical atomic model.

Explanation:

The atom model given by quantum mechanics is the most modern, precise and complex, based on the mathematical form of the atomic structure.

Quantum theory states that matter has properties associated with waves, which is why the atom model was based on this theory. The so-called “Uncertainty Principle” states that the electron has no exact position in the electrosphere, no definite speed and direction. This is why the Bohr atom, with electrons spinning in circular orbits, is surpassed by the quantum model.

Answer:

a) 7.1 x 10⁻⁵ : 2 significant figures

b) 0.00677 : 3 significant figures  

c) 750 : 2 significant figure  

Explanation:

The significant digits or figures refers to the digits of a given number that carry meaning and also contributes to precision of the given number.

a) 7.1 x 10⁻⁵ = 0.000071 : 2 significant figures, leading zeros are not significant.

b) 0.00677 : 3 significant figures, leading zeros are not significant.          

c) 750 : 2 significant figure, trailing zeros are not significant.        

Answer:

In the second step, the chemist must measure 8.3 ml of concentrated acid

Explanation:

The concentration of the final solution can be obtained using the pH value:

pH = -log[H] = 0.60

[H] = 10^(-0.60) = 0.25 M

Then, the final concentration of HCl will be 0.25 M because HCl is a monoprotic acid, which means that HCl only has one hydrolyzable proton. Therefore: [HCl] = [H].

The number of moles of HCl in the final solution will be equal to the number of moles present in the volume taken from the stock solution:

n° of moles in the volume taken from stock solution = n° moles in the final solution.

The number of moles can be calculated as follows:

number of moles = concentration * volume

Then:

Ci * Vi = Cf * Vf

where

Ci = concentration of the stock solution

Vi = volume taken from the stock solution

Cf = concentration of the final solution

Vf = volume of the final solution

Replacing with the data, we can obtain Vi:

6.0 M * Vi = 0.25 M * 200.0 ml

Vi = 8.3 ml

Answer:

The density of the metal is 21.675 g/mL.

The volume of metal with mass of 64.9 grams is 2.994 mL.

Explanation:

Density is defined as mass present in unit volume of the substance.

[tex]Density=\frac{Mass}{Volume}[/tex]

Mass of unknown metal = m = 427.0 g

Volume of the unknown metal = v = 19.7 mL

Density of the unknown metal = d

[tex]d=\frac{m}{v}=\frac{427.0 g}{19.7 mL}=21.675 g/mL[/tex]

Mass of the same unknown metal = M = 64.9 g

Volume of same unknown metal with mass M = V

Density of the metal  = d = 21.675 g/mL

[tex]21.675 g/ mL=\frac{64.9 g}{V}[/tex]

V = 2.994 mL

Answer: The molar solubility of carbon dioxide gas is 0.002 M

Explanation:

Henry's law states that the amount of gas dissolved or molar solubility of gas is directly proportional to the partial pressure of the liquid.

To calculate the molar solubility, we use the equation given by Henry's law, which is:

[tex]C_{CO_2}=K_H\times p_{liquid}[/tex]

where,

[tex]K_H[/tex] = Henry's constant = [tex]3.7\times 10^{-2}mol/L.atm[/tex]

[tex]p_{CO_2}[/tex] = partial pressure of carbonated drink = 0.51atm

Putting values in above equation, we get:

[tex]C_{CO_2}=3.7\times 10^{-2}mol/L.atm\times 0.51atm\\\\C_{CO_2}=1.887\times 10^{-2}mol/L=0.002M[/tex]

Hence, the molar solubility of carbon dioxide gas is 0.002 M

Answer:

0.019 mol/L

Explanation:

Given data

According to Henry's law, the solubility of a gas in a liquid is proportional to its partial pressure.

C = k × P

C = (3.7 × 10⁻² mol/L . atm) × 0.51 atm

C = 0.019 mol/L

Answer: Concentration of the chemist's sodium chloride solution is 34.4 mol/L.

Explanation:

Molarity of a solution is defined as the number of moles of solute dissolved per Liter of the solution.

[tex]Molarity=\frac{n\times 1000}{V_s}[/tex]

where,

n= moles of solute

[tex]V_s[/tex] = volume of solution in ml

Given : moles of [tex]NaCl[/tex] = 6.89

volume of solution = 200 ml

Putting in the values we get:

[tex]Molarity=\frac{6.89\times 1000}{200}=34.4mol/L[/tex]

Thus the concentration of the chemist's sodium chloride solution is 34.4 mol/L.

Answer:

The unit of A must be 'atm', and the units of B and C must be 'atmxK'.

If a system is at steady state it means the properties do not vary over time.

Explanation:

The units of pressure must be atm, bar, Pa or mmHg. If we use the atm unit the result of the equation should be the pressure in 'atm'. Thus, the unit of A must be 'atm', and the units of B and C must be 'atmxK'. So, If we replace the equation with the temperatures (T) in Kelvin (K) the result will be in 'atm'.

[tex]P (atm) = A(atm) + \frac{B(atm.K)}{T(K)} + \frac{C(atm.K)}{T(K)}[/tex]

Problem 2: If a system is at steady state it means the properties do not vary over time. This is the definition of a steady state. Also, every particular steady state will define their own properties but each steady state will no vary their properties over time.

Answer:

(CH₃)₃COCH3₃ and (CH₃)₂CHOCH₂CH₃

Explanation:

Isomers are compounds which have the same molecular formula. Constitutional isomers have different connectivity; the atoms are connected in different ways.

1. (CH₃)₃COCH₃

2. (CH₃)₂CHOCH3₃

3. (CH₃)₂CHOCH₂CH₃

Molecules 1 and 3 have the same formula (C₅H₁₂O) and are isomers. Molecule 2 is not an isomer. From the structural formula, it is clear that Molecules 1 and 3 have different connectivity.

Answer:

Explanation:

From literature, we know that the typical pka of a lysine side is 10.3.

Then we use the Henderson-Hasselbalch equation:

[tex]pH=pka+log\frac{[A^{-} ]}{[HA]}[/tex]

In this case, [A⁻] is the concentration of deprotonated lysine, and [HA] is the concentration of protonated lysine.

We put the data from the problem in the equation and calculate the ratio of deprotonated to protonated lysine:

[tex]7.5=10.5+log\frac{[A^{-} ]}{[HA]}\\-3.0=log\frac{[A^{-} ]}{[HA]}\\10^{-3.0}=\frac{[A^{-} ]}{[HA]}\\0.001=\frac{[A^{-} ]}{[HA]}[/tex]

Answer: This therapy is available for 15 days.

Explanation:

We are given:

Oral solution dosage = 75 mg/5 mL

To calculate the volume of oral situation for single dose per, we use unitary method:

The volume required for 75 mg of solution is 5 mL

So, the volume required for 300 mg of solution will be = [tex]\frac{5mL}{75mg}\times 300mg=20mL[/tex]

The total volume of the ranitidine bottle = 300 mL

To calculate the number of days, we divide the total volume of the bottle by the volume of dose taken per night, we get:

[tex]\text{Number of days}=\frac{\text{Total volume}}{\text{Volume of dose taken per night}}=\frac{300mL}{20mL}=15[/tex]

Hence, this therapy is available for 15 days.

Answer:

It is written differently.

Explanation:

The answer as given is not written correctly.

First, we must consider significant figures. Any non-zero number is a significant figure, and zeroes between significant figures are also significant, so 0.3065 has four significant figures and 138.03 has five significant figures. (Leading zeroes before the decimal point are not significant)

When two numbers are multiplied or divided, the answer has the same number of significant figures as the number that had the least number of significant figures. So in this case, the result will have four significant figures.

The result is written in scientific notation:

(0.3065)/(138.03) = 2.221 x 10⁻³

Answer:

A. The liquid propane in a gas grill burns in a flame.

Explanation:

Chemical changes is the change which occur when the substance combines with the another to form a completely new substance.

Considering Options B, C and D, the identity of each specie is not changed but the state is changed and thus, these are physical changes.

On the other hand, Option A, when propane is being burnt in the flame , it changes to gas and its identity is lost. Thus, is a chemical change.

The correct answer to the student's question is A, as the burning of liquid propane in a gas grill is a chemical process that results in the formation of new substances, which is the definition of a chemical change.

The student's question pertains to identifying a chemical process from a list of options. To differentiate between physical and chemical changes, we recall that a physical change is a change in the state or form of a substance without changing its chemical composition, whereas a chemical change results in the formation of one or more new substances with different properties.

Therefore, the correct answer to the question is option A, where the burning of liquid propane in a gas grill is a chemical process resulting in new substances.