Answer:
aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
Explanation:
A.
A 2.5 M solution of a weak acid is prepared. Using a pH meter, the pH is measured to be 5.1. Calculate the acid ionization constant, [tex]K_{a}[/tex] , of this weak acid.
Show your work
Molarity of acid=2.5M
pH=5.1.
ka=?
Now
We need to write an eqn to show the dissociation of the acid
HA + H2O === H3O+ + A-
Writing The Equilibrium(Or Acid dissociation constant) of this reaction
Ka =[H3O+] {A-]/ {HA].
The concept behind this is
concentration of Products divided by those of reactants. Water is not written because its a pure liquid and does not affect the Equilibrium constant.
Now If you have any Idea on ICE tables..
You'd know that the concentration of acid will decrease by 2.5-x
Whilst the products...will increase by x each
Note: This is when the ratio of their Moles are in 1:1
ka= x.x/2.5-x
Since the Moles of A- and H3O+ are in 1:1... Their concentrations at equilibrium will be the same
so
Ka= x²/2.5-x
Now what is x??
x is the Hydrozonium ion concentration.
we can get it from the pH formula
pH= -log (H3O+)
Making H3O+ subject by applying Logarithm Rules
H3O+ = 10^-ph
x=10^-5.1
=7.94x10^-6.
Now back to Ka
Ka= x²/2.5-x
Ka= (7.94x10^-6)²/2.5-(7.94x10^-6)
Ka= (7.94x10^-6)²/2.4999
Ka= 2.52x10^-11.
Was a Fun One
The ionization constant of this weak acid is [tex]2.52*10^{-11}[/tex]. The values can be substituted in dissociation formula.
What information do we have?
Molarity of acid=2.5M
pH=5.1
To find:
ka=?
Calculation of ionization constant:[tex]HA + H_2O < === > H_3O^+ + A^-[/tex]
The value of dissociation constant will be:
[tex]Ka =[H_3O^+] [A^-]/ {HA][/tex]
The Moles of A- and H3O+ are in 1:1.Their concentrations at equilibrium will be the same.
[tex]Ka= x.x/2.5-x\\\\Ka= x^2/2.5-x\\\\pH= -log (H_3O^+)\\\\H_3O^+ = 10^{-pH}\\\\x=10^{-5.1}\\\\x=7.94*10^{-6}[/tex]
[tex]Ka= x^2/2.5-x\\\\Ka= (7.94*10^{-6})^2/2.5-(7.94*10^{-6})\\\\Ka= (7.94*10^{-6})^2/2.4999\\\\Ka= 2.52*10^{-11}\\\\[/tex]
Thus, ionization constant of this weak acid is [tex]2.52*10^{-11}[/tex].
Find more information about ionization constant here:
brainly.com/question/2284518
HELP!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! Which of the following statements is true?
Some plants cannot reproduce.
Pollen contains male sperm cells.
Mitosis results in two non-identical cells.
Flowering plants reproduce using spores.
Answer:
errccvbnnbb
Explanation:
jjuxxxsyy
Answer:
i think it the third one
Explanation:
sorry if im wrong are u in biology?
how many cats are in the word
Answer: more than 70,00 and most of that population is living on the streets
When a lead acid car battery is recharged by the alternator, it acts essentially as an electrolytic cell in which solid lead(II) sulfate PbSO4 is reduced to lead at the cathode and oxidized to solid lead(II) oxide PbO at the anode.Suppose a current of 62.0 is fed into a car battery for 23.0 seconds. Calculate the mass of lead deposited on the cathode of the battery. Round your answer to 3 significant digits. Also, be sure your answer contains a unit symbol.
Answer: The mass of lead deposited on the cathode of the battery is 1.523 g.
Explanation:
Given: Current = 62.0 A
Time = 23.0 sec
Formula used to calculate charge is as follows.
[tex]Q = I \times t[/tex]
where,
Q = charge
I = current
t = time
Substitute the values into above formula as follows.
[tex]Q = I \times t\\= 62.0 A \times 23.0 sec\\= 1426 C[/tex]
It is known that 1 mole of a substance tends to deposit a charge of 96500 C. Therefore, number of moles obtained by 1426 C of charge is as follows.
[tex]Moles = \frac{1426 C}{96500 C/mol}\\= 0.0147 mol[/tex]
The oxidation state of Pb in [tex]PbSO_{4}[/tex] is 2. So, moles deposited by Pb is as follows.
[tex]Moles of Pb = \frac{0.0147}{2}\\= 0.00735 mol[/tex]
It is known that molar mass of lead (Pb) is 207.2 g/mol. Now, mass of lead is calculated as follows.
[tex]No. of moles = \frac{mass}{molar mass}\\ 0.00735 = \frac{mass}{207.2 g/mol}\\mass = 1.523 g[/tex]
Thus, we can conclude that the mass of lead deposited on the cathode of the battery is 1.523 g.
A substance in a specific state of matter with volume of 6 liters was transferred to a 12 liter container. The substance took up the
A. It is highly compressible.
B. It also has a definite shape.
C.Its particles slide past one another
D. Its intermolecular forces are of high strength.
[tex]\huge\color{yellow}\boxed{Answer:}[/tex]
My answer is C.Its particles slide past one another
[tex]\huge\color{yellow}\boxed{toshiro hitsugaya}[/tex]
When the 6 liters volume of the substance takes up 12 liter container, we conclude that the substace is highly compressible.
What is compressibility?
Compressibility is the measure of the relative volume change of a solid or a fluid with respect to pressure change.
Gases are the most compressible susbtance because most of the volume of a gas is composed of the large amounts of empty space between the gas particles.
Therefore, when the 6 liters volume of the substance takes up the entire volume of 12 liter container, we can conclude that the substace is highly compressible.
Learn more about compressibility here:https://brainly.com/question/1307771
describes the oil-free paint manufacturing process
Answer:
which account for over 60% of total resin use in the USA. The main pigment was titanium dioxide and the major solvents aliphatic hydrocarbons
Explanation:
12 points
Methyl methacrylate has a molar mass of 100 g/mole When a sample of methyl methacrylate weighing 3.14 g was completely combusted, the only products formed
were 6.91 g of CO2 and 2.26 g of water. What is methyl methacrylate's molecular formula?
O A C5H8O2
OBC6H120
OCC7H16
OD. None of the above
O E C4H403
Answer:
C₅H₈O₂
Explanation:
methyl methacrylate = 100 amu
6.91g CO₂ = 0.157 moles
2.26g H₂O = 0.125 moles
0.157 ÷ 0.125 = 1.256
{(CO₂)₁.₂₅₆ + (H₂O)₁} × 4 = (CO₂)₅ + (H₂O)₄
C₅H₈O?
C₅ = 60.05 amu H₈ = 8.064 amu
60.05 + 8.064 = 68.114 amu
100 amu - 68.114 amu = 31.886 amu
O = 16 amu
O = 2
The molecular formula of methyl methacrylate is C₅H₈O₂. The correct option is A, C₅H₈O₂.
What is methyl methacrylate?
Methyl methacrylate (MMA) is a colorless liquid monomer with a distinctive fruity odor. It is an organic compound that belongs to the family of acrylic esters.
We have to determine the empirical formula of methyl methacrylate first and then multiply it by the integer n to determine the molecular formula. Empirical formula:
CO₂ and H₂O are the combustion products of methyl methacrylate.
C₅H₈O₂ + (9n / 2)
O₂ → 5CO₂ + (n)H₂O
There are 5 C atoms and (8 + 2n), H atoms in the left and 5 C atoms, and n H atoms in the right.
5C = 5C, and 8 + 2n = nH.
n = 6
Molecular formula calculation is dividing the molecular weight by the empirical formula weight to determine the multiplication factor.
C₅HₙO₂ (empirical formula) has a weight of:
(5 x 12.011) + (8 x 1.008) + (2 x 15.999) = 100.12 g/mol
The actual molecular weight of methyl methacrylate is 100 g/mol.
Therefore, the molecular formula is (C₅H₈O₂) x 1, which is C₅H₈O₂, option A.
To know more about the molecular formula, Click here:
brainly.com/question/29435366
#SPJ2
What happens when an electron moves to a higher energy level?
A. It releases energy of a specific frequency
B. It gains energy in a quantized amount.
C. It loses energy in the form of light.
D. It absorbs photons of many energies
ANSWER: B. It gains energy in a quantized amount.
Answer:
B. It gains energy in a quantized amount.
How many ions are in 1
mole of potassium sulfate?
Answer:
We will need two potassium ions to balance the charge on the sulfate ion, so the proper chemical formula is K 2SO 4.
Explanation:
hope this helps
Astronauts must be protected from extreme heat while
reentering the Earth's atmosphere. Scientists can use the
engineering design process to help make reentry safer.
You have defined the problem as a need for heat shields to be stronger. What
should be your next step in using the engineering design process to solve the
problem?
O A. Communicate your solution to your team members.
O B. Update your initial design for the heat shield.
O C. Identify the criteria and constraints of the project.
O D. Build a prototype of a possible new type of heat shield.
The next engineering step to be taken is to update your initial design for the heat shield.
What is a heat sheild?The term heat sheild refers to a device that can be used to shield an from astronaut extreme heat especially as they re-enter the earth's atmosphere.
After you have identified the problem, the next engineering step to be taken is to update your initial design for the heat shield.
Learn more about heat sheild:https://brainly.com/question/21504467?
#SPJ2
What piece of apparatus could be used to measure the volume of gas produced in a reaction
1)beaker
2)gas syringe
3) top pan balance
Answer: 2)gas syringe
Explanation:
the volume of a gas is usually measured with a gas syringe (or sometimes with an upside-down measuring cylinder)
Answer:
top pan balance
Explanation:
In the calculations it was assumed that:
a. Before any acetic acid was added, essentially all the indicator was in the In-form.
b. After the HCl was added, essentially all the indicator was in the HIn form.
Required:
Justify these assumptions using the measured pH of these solutions and your experimental value for pKHIn to determine:
1. The fraction of the indicator in the HIn form in solution B before any of solution A was added.
2. The fraction of the indicator in the In- form after the HCl was added.
Answer:
Following are the responses to the given points:
Explanation:
Form the above-given question, it indicates that the bromate ion green ionizes in water to form a green-blue solution, therefore the before adding the HCL it indicator was in anionic from hence it is written as In^{-} therefore the HCL is mixed which the anion is protonated to give HIN
what are the products of this reaction
Cu+AgNO3
Answer:
1 Cu + AgNO3 → Ag + CuNO3
2 Cu + Ag(NO3)2 → Ag + CuNO3
Explanation:
plzzz mark me brainliest
A chemistry student needs 30.0 g of acetic acid for an experiment. He has available 1.2 kg of a 7.58% w/w solution of acetic acid in acetone.
Calculate the mass of solution the student should use. If there's not enough solution, press the "No solution" button.
Round your answer to 3 significant digits.
Answer:
The mass of solution will be "395.78 g".
Explanation:
Given:
Mass of acetic acid,
= 30 g
Percentage,
= 7.58% w/w
Now,
⇒ % [tex]=\frac{Mass \ of \ acetic \ acid}{Mass \ of \ solution}\times 100[/tex]
By putting the values, we get
⇒ [tex]7.58=\frac{30}{Mass \ of \ solution}\times 100[/tex]
⇒ [tex]Mass \ of \ solution=\frac{30\times 100}{7.58}[/tex]
⇒ [tex]=\frac{3000}{7.58}[/tex]
⇒ [tex]=395.78 \ g[/tex]
Questions
Determine the primary and secondary valencies of the following complexes and calculate their spin only magnetic
moment.
iii. [Cu(OH2)6]504
i. K[TI(CN).]
ii. [V(NH3)4Br2]
iv. K3 [Cr(CN)6]
Answer:
yes
Explanation:
yes
Will give brainliest
If it is 9 am in San Francisco, is it also 9 am in New York? Why or why not?
Answer:
no
Explanation:
Becasue time zones, San Fransico is in the west while New York is in the north New York is 3 hours ahead of California
Question 2 of 10
What is the purpose of the flame that is lit below a hot air balloon?
A. To increase enthalpy
B. To increase reduction
C. To decrease enthalpy
O D. To decrease specific impulse
Answer:
A is correct answer for your question. A
Explanation:
A P E X
The purpose of the flame that is lit below a hot air balloon is to Increase Enthalpy. Hence, Option (A) is Correct.
What is Enthalpy ?
A thermodynamic quantity equivalent to the total heat content of a system. It is equal to the internal energy of the system plus the product of pressure and volume.
A hot air balloon uses a burner to heat up the air inside the balloon. The burner is usually fueled by liquid propane. The burner mixes the fuel with air and ignites the mixture, which creates a flame directly underneath the bottom opening of the hot air balloon.
Once the air inside the balloon begins to get warm, the balloon will rise. The pilot controls the balloon’s altitude by releasing hot air from a vent at the top of the balloon, releasing the warmer air causes the balloon to descend.
Therefore, The purpose of the flame that is lit below a hot air balloon is to Increase Enthalpy. Hence, Option (A) is Correct.
Learn more about enthalpy here ;
https://brainly.com/question/13996238
#SPJ2
what volume of h2 can be produced at stp from 2 mol cah2 and excess water if the reaction goes 100% to completion?
Answer:
89.6 L of H₂ will be produced at STP from 2 moles of CaH₂ and excess water if the reaction goes to 100% completion.
Explanation:
The balanced chemical equation of the reaction between calcium hydride, CaH₂ and excess water to produce calcium hydroxide and hydrogen gas is given below:
CaH₂ (s) + 2H₂O (l) ----> Ca(OH)₂ (aq) + 2H₂ (g)
From the equation of the chemical reaction above, 1 mole of calcium hydride reacts with 2 moles of water to produce 2 moles of hydrogen gas.
Then, 2 moles calcium hydride will react with excess water to produce 2 × 2 -moles of hydrogen gas = 4 moles of hydrogen gas.
One mas a gas at STP has a volume of 22.4 L
4 moles of hydrogen gas will have a volume of 4 × 22.4 L = 89.6 L
Therefore, 89.6 L of H₂ will be produced at STP from 2 moles of CaH₂ and excess water if the reaction goes to 100% completion.
Hey duckers
Pp poopoo everyday
Answer:
So when a cat puts up its middle finger its usually trying to scare you off.
Explanation:
it's gonna kill you.
Which describes the burning of fossil fuels?
O A. Carbon dioxide is released into the atmosphere.
O B. Combustion causes greenhouse gases to break apart.
O C. It is an endothermic reaction.
O D. Crude oil forms during combustion,
Hi there! Let's tackle this together.
The answer to the question is option A.
When fossil fuels mined from the ground are burned with fire and sometimes crude oil, it releases toxic fumes which cause global warming. The same toxic fumes that come from these fossil fuels come from plastic.
The answer is option A.
The burning of fossil fuels yields carbon dioxide, water, and energy. The process of burning fossil fuels is known as “combustion”. So, option A describes the burning of fossil fuels.
What are fossil fuels?Fossil fuels are made from decomposing plants and animals. These fuels are found in the earth's crust and contain carbon and hydrogen, which can be burned for energy. Coal, Oil, and natural gas are examples of fossil fuels.
What is meant by combustion?Combustion is the chemical reaction that releases energy trapped in fossil fuels. Combustion is an exothermic reaction, which means that energy is released. Usually, heat and light are released during a combustion reaction. During exothermic reactions (like combustion), bonds are broken, which allows the energy trapped in the bonds to be released and do work.Combustion(burning) of fossil fuels:During the combustion of fossil fuels, the carbon compound in the fossil fuel reacts with oxygen in the presence of a heat source to form carbon dioxide (CO2) and water.Energy is also needed for the fossil fuel to react with oxygen, so the energy use portion of combustion is an endothermic reaction.Therefore, the burning of fossil fuels releases heat energy, and the primary byproduct of combustion is carbon dioxide (CO2).
Learn more about the combustion of fossil fuels here:
https://brainly.com/question/23992512
#SPJ2
A solution is prepared by dissolving solid ammonium nitrate, NH4NO3, in water. The initial temperature of the water was 25oC, but after the solid had dissolved, the temperature had fallen to 20oC. What conclusion may be made about delta H and delta S
Answer:
ΔH is positive, ΔS is positive
Explanation:
The enthalpy of reaction (ΔH) is positive in an endothermic reaction. An endothermic reaction leads to a decrease in temperature. Hence the fact that the temperature was decreased from 25oC to 20oC shows that the reaction is endothermic therefore ΔH is positive.
Also, the equation of the dissolution is;
NH4NO3(s) -----> NH4^+(aq) + NO3^-(aq)
This means that the number of particles in solution were increased. The entropy increases with increase in number of particles hence ΔS is positive.
When the ocean absorbs CO2, the pH of the ocean water drops. What's the
effect of this process?
A. The hydrogen ion concentration increases.
B. The amount of water in the ocean increases.
C. The hydroxide ion concentration increases.
O D. The balance of H+ and OH ions is the same.
SUBMIT
Answer:
the amount of water
in the ocean increases
Answer:
A. The hydrogen ion concentration increases.
Pls help I will give brainliest
Answer:
paki sagot naman pls para my isagot ako sa module ko ty
In science, we like to develop explanations that we can use to predict the outcome of events and phenomena. Try to develop an explanation that tells how much NaOH needs to be added to a beaker of HCl to cause the color to change. Your explanation can be something like: g
The question is incomplete. The complete question is :
In science, we like to develop explanations that we can use to predict the outcome of events and phenomena. Try to develop an explanation that tells how much NaOH needs to be added to a beaker of HCl to cause the color to change. Your explanation can be something like: The color change will occur when [some amount] of NaOH is added because the color change occurs when [some condition]. The goal for your explanation is that it describes the outcome of this example, but can also be used to predict the outcome of other examples of this phenomenon. Here's an example explanation: The color of the solution will change when 40 ml of NaOH is added to a beaker of HCl because the color always changes when 40ml of base is added. Although this explanation works for this example, it probably won't work in examples where the flask contains a different amount of HCl, such as 30ml. Try to make an explanation that accurately predicts the outcome of other versions of this phenomenon.
Solution :
Consider the equation of the reaction between NaOH and [tex]$HCl$[/tex]
NaOH (aq) + HCl (aq) → NaCl(aq) + [tex]$H_2O (l)$[/tex]
The above equation tells us that [tex]$1 \text{mole}$[/tex] of [tex]$NaOH$[/tex] reacts with [tex]$1 \text{mole}$[/tex] of [tex]$HCl$[/tex].
So at the equivalence point, the moles of NaOH added = moles of [tex]$HCl$[/tex]present.
If the volume of the [tex]$HCl$[/tex] taken = [tex]$V_1$[/tex] mL and the conc. of [tex]$HCl$[/tex] = [tex]$M_1$[/tex] mole/L
The volume of NaOH added up to the color change = [tex]$V_2 \text{ and conc of NaOH = M}_2$[/tex] mole/L
Moles of [tex]$HCl$[/tex] taken = [tex]$V_1 \ mL \times M_1 \ mol/100 \ mL = V_2M_2 \times 10^{-3}$[/tex] moles.
The color change will occur when the moles of NaOH added is equal to the moles of [tex]$HCl$[/tex] taken.
Thus when [tex]$V_1 M_1 \times 10^{-3} = V_2M_2 \times 10^{-3}$[/tex]
or when [tex]$V_1M_1 = V_2M_2$[/tex]
or [tex]$V_2=\frac{V_1M_1}{M_2}$[/tex] mL of NaOH added, we observe the color change.
Where [tex]$V_1, M_1$[/tex] are the volume and molarity of the [tex]$HCl$[/tex] taken.
[tex]$M_2$[/tex] is the molarity of NaOH added.
When both the NaOH and [tex]$HCl$[/tex] are of the same concentrations, i.e. if [tex]$M_1=M_2$[/tex], then [tex]$V_2=V_1$[/tex]
Or the 40 mL of [tex]$HCl$[/tex] will need 40 mL of NaOH for a color change and
30 mL of [tex]$HCl$[/tex] would need 30 mL of NaOH for the color change (provided the concentration [tex]$M_1=M_2$[/tex])
Ionic bonds result from elements ____.
A. that share electrons
B. with high electronegativity differences
C. That form polar bonds
D. That are only nonmetals
what is solubility? .
Which of the following are TRUE about why proteins are important for our body?
Group of answer choices
Proteins give structure to our hair and nails.
Proteins make up hormones and antibodies.
Proteins make up digestive enzymes, like lipase, amylase, and pepsin which aid in breaking down our food.
The protein, insulin, helps carry out muscle contraction.
The protein, myosin, helps carry out muscle contraction.
The protein, hemoglobin, carries substances throughout our body and is a key part of our ciruclatory system.
Answer:
The protein,hemoglobin,carries substances throughout our body and js a key part of our curuclatory syatem
Explanation:
yan lang po alam ko di ko po sure eh
4. What characteristic of an element differs between isotopes?
a. Negative charge
b. Mass
c. Positive charge
d. All of the Above
The characteristic of an element that differs between isotopes is the Mass (Option b).
What are isotopes?Isotopes are elements that exhibit an equal atomic number but distinct nucleonic number.
Isotopes contain different numbers of protons in their atomic nuclei (atomic weight).
In conclusion, the characteristic of isotopes is the Mass (Option b).
Learn more about isotopes here:
https://brainly.com/question/14220416
#SPJ1
What is the the heat of reaction, delta, in kJ/mol?
a) -26kJ/mol
b) -25kJ/mol
c) -10kJ/mol
d)-35kJ/mol
Answer:
b) -25 kJ/mol.
Explanation:
Hello there!
In this case, since the general definition of the enthalpy of reaction involves the subtraction of the energy of the products and the energy of the reactants:
[tex]\Delta H=H_{prod}-H_{react}[/tex]
Thus, since the graph shows that the energy of the products is 20 kJ/mol and that of reactants 45 kJ/mol, we will obtain:
[tex]\Delta H=20kJ/mol-45kJ/mol\\\\\Delta H=-25kJ/mol[/tex]
Which means it is exothermic.
Regards!
sodium is an inactive metal why
Answer:
Inactive metals are inert metals that doesn’t react with most of the chemicals.They are highly resistant to oxidation and corrosion when exposed to moisture.
Explanation: