Answer: Avogadro's Hypothesis simply states that all gases of equal volume have the same number of molecules.
Explanation: Avogadro's Hypothesis is an experimental gas law and it serves as a specific case of the ideal gas law. Mathematically,
Volume (V) is proportional to the Number of mole (n) of the gas
V/n = K
Where K is the constant of proportionality.
Avogadro's hypothesis states that equal volumes of gases contain the same number of particles. It is an important concept in the study of gases.
Explanation:Avogadro's hypothesis states that equal volumes of gases, at the same temperature and pressure, contain the same number of particles. This hypothesis helps explain the concept of molar volume and is a fundamental principle in the study of gases. For example, 1 mole of any gas occupies the same volume as 1 mole of any other gas at the same temperature and pressure.
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Transportation is the largest single source of air pollution in the United States. Air pollution can harm the environment and human health. Which technology could offer a solution to this problem? mufflers that reduce noise motors that run on electricity tires that improve gas mileage
Answer:
- motors that run on electricity
- tires that improve gas mileage
Explanation:
The transportation is a major polluter of the air. The big problem with it is that it is necessary for the humans to be able to live and function properly, as the trade is happening through it, thus it is crucial for the economy. In order to stop or reduce the negative impact on the air quality, there are some solutions which can help. The motors that can run on electricity are an excellent method, as the production of electricity is not polluting the are as the fossil fuels are. The only problem is that this type of motors are still very expensive, so once their price is on pair with the combustion motors they can be used. Tires that are able to increase the efficiency of the transportation means can also be useful, as they will be able to reduce the amount of pollutants released into the atmosphere, because the transportation will use less fossil fuels for the same mileage.
Answer:
Explanation:
Under the sector of transportation passenger vehicles are the major contributor to the pollution. Emission from cars and two-wheeler is the leading cause of increasing level of carbon dioxide, sulfur content and other greenhouse gases.
Solution to this problem include:
Increase in usage of electric vehicles as seen in Norway.Better tires which can improve the fuel mileage.Encourage usage of public transport.why are halogens kept in the group 17 of modern peroidic table?
Halogens are in Group 17 of the periodic table because they have seven valence electrons, making them highly reactive as they seek one more electron to achieve a full octet. Their ability to readily form singly negative ions and salts when reacting with metals further characterizes their group placement.
Halogens are kept in Group 17 (also known as Group VIIA) of the modern periodic table because of their distinctive chemical properties. Each halogen has seven valence electrons (a p⁵ configuration in their outermost p subshell), which is just one electron short of completing their outer shell. Thus, they are highly reactive, as they need only one additional electron to achieve a stable, noble gas electron configuration.
The reactivity of halogens also allows them to form singly negative ions, such as Cl-, by accepting an extra electron into the vacancy in their outer p subshell. This contrasts with alkali metals that reside in Group 1, which easily give up their single s electron to form singly positive ions like Na+. Because halogens readily combine with metals to form salts, such as sodium chloride, they are known as "salt-forming" or halogens.
Moreover, the physical states of halogens at room temperature are diverse: chlorine is a gas, bromine is a liquid, and iodine and astatine are solids. This variation doesn't affect their placement in Group 17, which is based on their shared electronic configuration and chemical properties.
Element
Mass Number
Atomic Number
Aluminum
27
13
Nitrogen
14
7
Helium
4
2
Fluorine
19
9
Which element has the most neutrons in the nucleus?
Aluminum
Nitrogen
Helium
Fluorine
Answer:
Aluminum
Explanation:
An atom of any elements has an outer electron and a proton and neutron located in the nucleus . The proton and neutron found in the nucleus of an atom determine the mass number of an element. The mass number of an element is the sum of the proton(atomic number) and the neutron number.
Mathematically,
Mass number = proton number(atomic number) + neutron number
Therefore,
neutrons number = mass number - proton number
Aluminium has the highest neutron
neutron = 27 - 13 = 14
Neutron of aluminium = 14
Final answer:
Aluminum, with a mass number of 27 and an atomic number of 13, has the most neutrons in its nucleus among the given elements, totaling 14 neutrons.
Explanation:
To determine which element has the most neutrons in its nucleus, we need to subtract the atomic number from the mass number for each element. The atomic number represents the number of protons, and the mass number is the sum of protons and neutrons in the nucleus.
Aluminum has a mass number of 27 and an atomic number of 13, resulting in 27 - 13 = 14 neutrons.
Nitrogen has a mass number of 14 and an atomic number of 7, resulting in 14 - 7 = 7 neutrons.
Helium has a mass number of 4 and an atomic number of 2, resulting in 4 - 2 = 2 neutrons.
Fluorine has a mass number of 19 and an atomic number of 9, resulting in 19 - 9 = 10 neutrons.
Comparing the number of neutrons calculated for each element, we can see that Aluminum has the most neutrons in its nucleus.
Which of the following lists the atmospheric layers in the correct order beginning at the Earth's surface?
Answer:Troposphere, Stratosphere, Mesosphere and Thermosphere
Explanation:
Once formed how are coordinates covalent bonds different for other covalent bonds?
Answer:
Explanation:
Coordinate covalent bonds differs from other types of covalent bonds in that the two atoms bonds in such a way that one member of the bonding pair supplies both electrons to be shared. In normal covalent bonds, both atoms supplies the electrons to be shared.
This type of bond is used to join two covalent compounds together. They can also be used in joining protons to neutral covalent molecules together.
Final answer:
Once established, coordinate covalent bonds are indistinguishable in strength and function from other covalent bonds.
Explanation:
The question asks about the difference between a coordinate covalent bond and other covalent bonds once they are formed. A coordinate covalent bond is a type of covalent bond where a single atom provides a pair of
electrons for the bond, while a regular covalent bond involves each atom contributing one electron to the shared pair. A classic example of a coordinate covalent bond is found in the carbon monoxide molecule (CO), where one of the three bonds between carbon and oxygen is a coordinate covalent bond because oxygen donates both electrons for that bond.
However, once formed, a coordinate covalent bond is just as strong and behaves in the same way as any other covalent bond.
Atoms typically form a characteristic number of covalent bonds that can include double bonds or triple bonds, as depicted in Lewis electron dot diagrams. Whether a bond is a coordinate covalent bond or not does not affect the eventual strength or final properties of the bond.
The pressure on 7.0 L of gas is increased from 15 psi to 1420 torr, at constant
temperature. What is the new volume of the gas?
Answer:
3.85L
Explanation:
Given parameters:
Initial pressure P₁ = 15psi (1psi = 52mmHg)
converting to mmHg gives (15x52)mmHg = 780mmHg
Initial volume V₁ = 7.0L
Final pressure P₂ = 1420torr= 1420mmHg
Unknown:
Final volume V₂ = ?
Condition of the process: Constant temperature
Solution
To solve this problem, we simply apply Boyle's law. Boyle's law states that "The volume of a given mass of gas varies inversely as the pressure changes, if the temperature is constant".
It is mathematically expressed as ;
P₁V₁ = P₂V₂
The unknown here is V₂ and we simply express it as the subject of the formula:
V₂ = [tex]\frac{P_{1} V_{1} }{P_{2} }[/tex]
V₂ = [tex]\frac{780 x 7 }{1420}[/tex]
V₂ = [tex]\frac{5460}{1420}[/tex] = 3.85L
why is radioactive dating important when approximating the age of earth?
Answer:
So, we rely on radiometric dating to calculate their ages. Radiometric dating, or radioactive dating as it is sometimes called, is a method used to date rocks and other objects based on the known decay rate of radioactive isotopes.
Explanation:
radiometric dating is a very accurate way to date the Earth.We know it is accurate because radiometric dating is based on the radioactive decay of unstable isotopes. When an unstable Uranium (U) isotope decays, it turns into an isotope of the element Lead (Pb).
Answer:
The radioactive dating method is one of the efficiently used methods in order to calculate the age of the rocks, meteorites, fossils and various other objects, depending upon the rate at which radioactive isotopes decay. In this method, an unstable element changes into a stable one, releasing some amount of radiation and losing a certain amount of energy.
This is efficient in determining the age of the earth. The earth is comprised of rocks that are present from the time of its formation. These rocks can be dated using this method and the approximate age of the rock is evaluated.
The Uranium-Lead dating (²³⁸U-²⁰⁶Pb) method was used to date the smaller zircon crystals of Australia that are about 4.4 billion years old. The half-life of U-238 is approximately 4.5 billion years, which shows that these are one of the oldest rocks on earth and helps in understanding how old the earth is.
Half-life is defined as the time required by a radioactive isotope to decay half of its atoms.
So the radioactive dating method is one of the common method gives the approximate age of the earth.
An object was measured by a worker as
14.6cm long, however, the manufacturer
specifications list the length of the object at
14.4cm. What is the percent error in the
worker's measurement?
The percent error in the worker's measurement, when compared to the manufacturer's specifications, is 1.39%.
To calculate the percent error in the worker's measurement, we need to compare the measured value to the accepted value given by the manufacturer's specifications. The formula to determine percent error is:
[tex]Percent\ Error = |\frac{Measured\ Value\ -\ True\ Value}{True\ Value}| \times 100\%[/tex]
In this case:
Measured Value = 14.6 cmTrue Value = 14.4 cmApplying the values to the formula, we get:
[tex]Percent\ Error = |\frac{14.6 cm - 14.4 cm}{14.4 cm}| \times 100\% = |\frac{0.2 cm}{14.4 cm}| \times 100\% = 0.0139 \times 100\% \\ = 1.39\%[/tex]
Therefore, the percent error in the worker's measurement is 1.39%.
The Δ symbol in a chemical equation means _____.
Answer:
heat is supplied to the reaction
Answer:
The Δ symbol in a chemical equation means energy in form of heat is provided to the system.
Explanation:
When the Δ symbol is above or under the arrow of a chemical reaction representation it is indicating that the reagents must be heated to obtain the products. i.e. is representing an endothermic reaction in which energy must be provided to the system for the reaction to occur.
What is the morality of 2.50 L of solution that contains 1.85 mol of anhydrous sodium tetraborate?
The morality, or molarity, of a 2.50 L solution containing 1.85 mol of anhydrous sodium tetraborate is calculated by dividing the amount of solute by the volume, yielding a concentration of 0.74 M.
The morality of a 2.50 L solution containing 1.85 mol of anhydrous sodium tetraborate refers to its molar concentration, which is expressed in moles per liter (mol/L). To find the morality, also known as molarity, you would divide the number of moles of solute by the volume of the solution in liters.
Molarity (M) = moles of solute / volume of solution in liters
Therefore, the molarity of the sodium tetraborate solution is:
M = 1.85 mol / 2.50 L
M = 0.74 M
How is an endothermic reaction identified
Answer:
An endothermic reaction is identified by noting the drop in temperature in the system.
Explanation:
An endothermic reaction occurs by absorbing heat energy from the environment( apparatus and solution). Once the energy in the surrounding reduces the temperature drops. The energy absorbed is used to form new bonds. The energy absorbed is directly proportional to the temperature drop.
Answer:
An endothermic reaction absorbs heat from its surroundings.
Explanation:
An example is the reaction of acetic acid with baking soda.
Three ways to tell if a reaction is endothermic:
Do the experiment. The system cools down, and you can use a thermometer or your hand to tell that the flask becomes colder .Heat will appear as a reactant in the chemical equation:CH₃COOH + NaHCO₃ + heat ⟶ CH₃COONa + H₂O + CO₂ The sign of ΔH is positive. N₂ + 2O₂ ⟶ 2NO₂ ; ΔH = +33.1 kJ·mol⁻¹The molar volume of a gas at STP, in liters, is
define molecules as it relates to molecular substances and compounds
Answer:
molecules are 2 atoms held together by chemical bonds, compunds are 2 atoms from more than one element held together by chemical bonds.
Molecule is the combination of two or more different atoms and Group of similar molecules forms compound.
What are the properties of a Molecule ?
Molecule is an electrically neutral group of two or more atoms held together by chemical bonds.
A molecule is the smallest particle into which an element or a compound can be divided without changing its chemical and physical properties.
Therefore, Molecule is the combination of two or more different atoms and Group of similar molecules forms compound.
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Both amines and amides are derivatives of ammonia. True False
It is true that both amides and amine are the derivatives of ammonia.
Explanation:Amines are the derivatives of ammonia [tex]\text{(NH_3)}[/tex] where nitrogen atom makes bond to 1, 2, or 3 alkyl or aromatic groups of compounds. Amides are the amino group [tex]\text{(-NH_2)}[/tex], which is derived from ammonia, replaces the hydroxyl group [tex]\text{(-OH)}[/tex] in a carboxylic acid.
The simplest amides are the proper derivation of ammonia whereas the higher degree amides are the derivation of secondary amine.
The statement is correct. Amines and amides are in fact derivatives of ammonia. Amines are derived from ammonia by replacing hydrogen atoms by alkyl or aryl groups, while amides are derived by replacing one hydrogen with an acyl group.
Explanation:Yes, the statement is correct. Amines and amides are indeed derivatives of ammonia.
Amines are organic compounds which are derived from ammonia by replacing one or more hydrogen atoms by alkyl or aryl group. For example, methylamine CH3NH2 is an amine where one hydrogen atom is replaced by a methyl group.
Amides, on the other hand, are organic compounds derived from ammonia by replacing one hydrogen atom by an acyl group. An example of an amide is acetamide CH3CONH2 where one hydrogen atom of ammonia is replaced by an acetyl group.
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A solution is made by dissolving 19.5 grams of glucose (C6H12O6) in 0.245 kilograms of water. If the molal freezing point constant for water (Kf) is -1.86 °C/m, what is the resulting Δtf of the solution? Show all he steps taken to solve this problem.
Will make brainliest!!
20 points!!
Answer:
- 0.8217°C.
Explanation:
We can solve this problem using the relation:ΔTf = Kf.m,
ΔTf is the depression in the freezing point.
Kf is the molal freezing point constant for water (Kf = -1.86 °C/m).
m is the molality of glucose.
We need to calculate the molality:Molality (m) is the no. of moles of solute in 1.0 kg of solvent.
∴ m = (mass/molar mass) of glucose/(mass of water (kg))
∴ m = (19.5 g/180.156 g/mol)/(0.245 kg) = 0.4418 m.
∴ ΔTf = Kf.m = (-1.86 °C/m)(0.4418 m) = - 0.8217°C.
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Which of the following is an element???
Answer:
B) C2
Explanation:
C2 is oxygen and oxygen is an element :)
Answer:
A is water
B is an oxygen molecule
C is an organic compound
The answer is B
Which of the following elements would you expect to have the lowest ionization energy value? Fluorine, lithium, neon, nitrogen
Answer:
Lithium (Li)
Explanation:
Lithium had the lowest ionization energy value because it has a low effective nuclear charge and a large radius
Answer:
lithium
Explanation:
Write the balanced
chemical equation for the reaction. If a plant has 88.0 g carbon diox-
ide and 64.0 g water available for photosynthesis, determine
a. the limiting reactant.
b. the excess reactant and the mass in excess.
c. the mass of glucose produced.
The balanced chemical equation for photosynthesis is 6CO2(g) + 6H2O(l) → C6H12O6(s) + 6O2(g), with water being the limiting reactant and carbon dioxide in excess. The mass of excess CO2 and the mass of glucose produced is determined by stoichiometric calculations.
Explanation:The balanced chemical equation for photosynthesis is 6CO2(g) + 6H2O(l) → C6H12O6(s) + 6O2(g). This shows that carbon dioxide (CO2) and water (H2O) react to form glucose (C6H12O6) and oxygen (O2). To find the limiting reactant, you convert the masses given for CO2 and H2O to moles using their respective molar masses (44.01 g/mol for CO2 and 18.02 g/mol for H2O). You would find that water is the limiting reactant because there are fewer moles of H2O than CO2 when compared to the stoichiometric coefficients in the balanced equation.
To find the excess reactant, subtract the amount of CO2 that would react with the available H2O from the initial amount of CO2 to determine the mass in excess. For the mass of glucose produced, use the mole ratio from the balanced equation, multiplied by the number of moles of the limiting reactant and then by the molar mass of glucose (180.16 g/mol).
How many grams of aluminum will there be in 98g of Al2O3?
Answer:
51.88 grams
Explanation:
make it in ratio form
Al=27×2=54.
54:48
(54/102)×98
=51.88 grams
O=16×3=48
(48/102)×98
=46.12 grams
how many molecules of water are in 345g
Answer:
1.15 molecules
Explanation:
To get to molecules, you need to first convert grams into moles, then moles into molecules.
345g of water x [tex]\frac{1 mol }{18.02g}[/tex]
This will get you the moles of water. (The number 18.02 came form the molar mass of water which is H2O)
I MOLE EQUALS AVOGADRO'S NUMBER
19.15 mol of water x[tex]\frac{6.022*10^{23}molecules }{1 mol}[/tex]
= 1.15
Answer:
There are [tex]1.1542\times 10^{25} [/tex] molecules of water are in 345 grams.
Explanation:
[tex]n=\frac{m}{M}[/tex]
[tex]N=n\times N_A[/tex]
Where:
m = mass of compound
M = Molar mass of compound
N = Number of particles / atoms/ molecules
n = Number of moles
[tex]N_A=6.022\times 10^{23} mol^{-1}[/tex] = Avogadro's number
Mass of water = m = 345 g
Molar mas of water = M = 18 g/mol
[tex]n=\frac{345 g}{18 g/mol}=19.167 mol[/tex]
Number of molecules of water = N
[tex]N=19.167 mol\times 6.022\times 10^{23}mol^{-1}[/tex]
[tex]N = 1.1542\times 10^{25} molecules[/tex]
There are [tex]1.1542\times 10^{25} [/tex] molecules of water are in 345 grams.
Where are the products in a chemical equation located
A On the left side of the snow in the equation
. On the night wide of the arrow in the equation
C. Between the reactants of the chemical equation
. At the beginning of the chemical equation
O
O
Answer:
the answer is B
Explanation:
reactants are on the left because they are the ones reacting. products are on the right because they are the final products.
How do you identify the anode on a power source such as a battery? How do you identify the cathode? How are terms anion and cation?
Answer:
On a power source such as a battery, the anode is labelled with a + (plus)
The cathode on the other side is labelled with a - (minus)
When ionic compounds ionize, they produce both positive and negative ions.
Anion- This is a negatively charged ion for example chloride ion (Cl⁻)
Cation- This is a positively charged ion for example sodium ion (Na⁺)
Express the following number in scientific notation.
0.026890 =
To express 0.026890 in scientific notation, it is written as 2.6890 x [tex]10^{-2}[/tex].
Express the following number in scientific notation:
0.026890 = 2.6890 x [tex]10^{-2}[/tex]
Scientific notation is a way to represent very large or very small numbers more concisely. It is written as a number between 1 and 10 multiplied by a power of 10.
Which of the following is an example of point-source pollution? A. Salt from roads B. Water from a sewage treatment plant C. Fertilizer from agricultural runoff D. Acid from abandoned mines
Answer:
Acid from abandoned mines- D.
Answer:
Water from a sewage treatment plant
Explanation:
Water from a sewage treatment plant is an example of point-source pollution.
When the pressure that a gas exerts
on a sealed container changes from
22.5 psi to_ psi, the
temperature changes from 110°C to
65.9°C.
The answer is:
When the pressure that a gas exerts on a sealed container changes from
22.5 psi to 19.86 psi, the temperature changes from 110°C to
65.9°C.
Why?To calculate which is the last pressure, we need to use Gay-Lussac's law.
The Gay-Lussac's Law states that when the volume is kept constant, the temperature (absolute temperature) and the pressure are proportional.
The Gay-Lussac's equation states that:
[tex]\frac{P_1}{T_1}=\frac{P_2}{T_2}[/tex]
We are given the following information:
We need to remember that since the temperatures are given in Celsius degrees, we need to convert it to Kelvin (absolute temperature) before use the equation, so:
[tex]P_1=22.5Psi\\T_1=110\°C=110\°C+273.15=383.15K\\T_1=65.9\°C=65\°C+273.15=338.15K[/tex]
Now, calculating we have:
[tex]\frac{P_1}{T_1}*(T_2)=P_2\\\\P_2=\frac{P_1}{T_1}*(T_2)=\frac{22.5Psi}{383.15}*338.15=19.86Psi[/tex]
Hence, the final pressure is equal to 19.86 Psi.
Have a nice day!
Answer:
The final pressure at 65.9°C is 19.91 psi.
Explanation:
To calculate the final pressure of the system, we use the equation given by Gay-Lussac Law.
This law states that pressure of the gas is directly proportional to the temperature of the gas at constant pressure.
Mathematically,
[tex]\frac{P_1}{T_1}=\frac{P_2}{T_2}[/tex] (at constant Volume)
where,
[tex]P_1\text{ and }T_1[/tex] are the initial pressure and temperature of the gas.
[tex]P_2\text{ and }T_2[/tex] are the final pressure and temperature of the gas.
We are given:
[tex]P_1=22.5 psi\\T_1=110^oC=383.15 K\\P_2=?\\T_2=65.9^oC=339.05 K[/tex]
Putting values in above equation, we get:
[tex]\frac{22.5 psi}{383.15 K}=\frac{p_2}{339.05 K}[/tex]
[tex]P_2=\frac{22.5 psi}{383.15 K}\times 339.05 K=19.91 psi[/tex]
The final pressure at 65.9°C is 19.91 psi.
If a simple machine aduces the strength of a force, what must be increased?
the speed of the input force
the work the simple machine performs
the size of the simple machine
the distance over which the force is applied
Answer:
the work the simple machine performs (second choice)
3. How many electrons are present in 1.6 g of methane?
Answer:
They present 1 electron
Complete the paragraph to describe the characteristics of a silicon tetrahydride molecule (SiH4). The Lewis structure and table of electronegativities are given.
The bond polarities of SiH4 are , the molecular shape is , and the molecule is .
Answer:
PLATO: Polar, Tetrahedral, NonPolar
Explanation:
Blood serum is typically about 0.0044 M in K+ (aq). Calculate the mass of the potassium ions in 4,785. mL of blood serum. The molar mass of potassium is 39.10 g/mol
Answer:
0.823 g.
Explanation:
Molarity (M) is defined as the no. of moles of solute dissolved in a 1.0 L of the solution.M = (no. of moles of K⁺)/(Volume of the solution (L).
∵ no. of moles of K⁺ = (mass/molar mass) of K⁺.
∴ M = (mass/molar mass) of K⁺/(Volume of the solution (L).
M = 0.0044 M.
Volume of the solution = 4785.0 mL = 4.785 L.
mass of K⁺ = ??? g.
molar mass of K⁺ = 39.01 g/mol.
∴ mass of K⁺ = (M)((molar mass of K⁺)(volume of the solution (L)) = (0.0044 M)(39.10 g/mol)(4.785 L) = 0.823 g.
The following questions A24 - A26 relate to 100 ml of 0.0150 M solution of benzoic acid
(C6H3COOH). Ka(C6H3COOH) = 6.4 x 10^-5.
What is the pH of the solution after the addition of 1 x 10^-3 moles of NaOH? You may assume no volume change to the solution upon addition of the NaOH.
Answer:
PH of the weak acid: approximately 2.513.
PH of the buffer solution: approximately 4.495.
Explanation:
The Ka value of benzoic acid is much smaller than 1. Benzoic acid will dissociate but only partially when dissolved in water. Construct a RICE table for this process. Let the equilibrium of [tex]\rm H^{+}[/tex] be [tex]x\; \rm mol\cdot L^{-1}[/tex]. Note that [tex]x \ge 0[/tex].
[tex]\displaystyle \begin{array}{c|ccccc}\textbf{R}&\mathrm{C_6H_5COOH} & \rightleftharpoons & \mathrm{C_6H_5COO^{-}} & + &\mathrm{H^{+}}\\\textbf{I} & 0.015 & & 0 & & 0\\\textbf{C} & -x & & +x & & +x\\\textbf{E} & 0.015-x & & x & & x\end{array}[/tex]
[tex]\displaystyle \frac{[\mathrm{C_6H_5COO^{-}}]\cdot [\mathrm{H^{+}}]}{[\mathrm{C_6H_5COOH}]} = \mathrm{pK}_{a}[/tex].
[tex]\displaystyle \frac{x^{2}}{0.015 - x} = 6.4\times 10^{-5}[/tex].
Solve this quadratic equation for [tex]x[/tex]:
[tex]x^{2}+ 6.4\times 10^{-5}\;x - 6.4\times 10^{-5}\times 0.150 = 0[/tex].
[tex]\displaystyle x = \frac{-6.4\times 10^{-5} \pm \sqrt{(6.4\times 10^{-5})^{2} - 4\times (- 6.4\times 10^{-5}\times 0.150)}}{2}[/tex].
Take only the non-negative root. [tex]x \approx 0.00306655[/tex].
[tex]\rm [H^{+}] = 0.00306655\; mol\cdot L^{-1}[/tex].
[tex]\displaystyle \mathrm{pH} = -\log_{10}{[\mathrm{H^{+}}]} = 2.513[/tex].
Each benzoic acid contains only one carboxyl group [tex]\mathrm{-COOH}[/tex]. Benzoic acid is thus a monoprotic acid. Each mole of the acid will react with only one mole of [tex]\rm NaOH[/tex]. The 100 mL solution initially contains [tex]1.50\times 10^{-3}[/tex] moles of benzoic acid. The [tex]1\times 10^{-3}[/tex] moles of [tex]\rm NaOH[/tex] will neutralize only part of the acid. The solution will eventually contain [tex]1\times 10^{-3}[/tex] moles of [tex]\mathrm{C_6H_5COO^{-}}[/tex] (from the salt [tex]\mathrm{C_6H_5COONa}[/tex]) and [tex]0.50\times 10^{-3}[/tex] moles of [tex]\mathrm{C_6H_3COOH}[/tex].
Both the acid [tex]\mathrm{C_6H_5COOH}[/tex] and the conjugate base of the acid [tex]\mathrm{C_6H_5COO^{-}}[/tex] exist in large amounts in the solution. Apply the Henderson-Hasselbalch equation for weak acid buffers to find the pH of this buffer solution.
[tex]\mathrm{pK}_{a} = -\log_{10}{\mathrm{K}_{a}} \approx 4.19382[/tex] for benzoic acid.
[tex]\begin{aligned}\mathrm{pH} &= \mathrm{pK}_{a} + \log{\frac{{[\text{Conjugate Base}]}}{[\text{Weak Acid}]}} \\ &= \mathrm{pK}_{a} + \log{\frac{{[\mathrm{C_6H_5COO^{-}}]}}{[\mathrm{C_6H_5COOH}]}}\\ &= 4.19382 + \log{\frac{0.01}{0.005}}\\ &\approx 4.495 \end{aligned}[/tex].