Answer:
uty tyuuuuuuuuuA) 1,280
B) 320
C) 144
C) 80
Explanation:
A) 1,280
B) 320
C) 144
C) 80
If 21.00 mL of a 0.68 M solution of C6H5NH2 required 6.60 mL of the strong acid to completely neutralize the solution, what was the final pH at the equivalence point
Answer:
pH = 2.46
Explanation:
Hello there!
In this case, since this neutralization reaction may be assumed to occur in a 1:1 mole ratio between the base and the strong acid, it is possible to write the following moles and volume-concentrations relationship for the equivalence point:
[tex]n_{acid}=n_{base}=n_{salt}[/tex]
Whereas the moles of the salt are computed as shown below:
[tex]n_{salt}=0.021L*0.68mol/L=0.01428mol[/tex]
So we can divide those moles by the total volume (0.021L+0.0066L=0.0276L) to obtain the concentration of the final salt:
[tex][salt]=0.01428mol/0.0276L=0.517M[/tex]
Now, we need to keep in mind that this is an acidic salt since the base is weak and the acid strong, so the determinant ionization is:
[tex]C_6H_5NH_3^++H_2O\rightleftharpoons C_6H_5NH_2+H_3O^+[/tex]
Whose equilibrium expression is:
[tex]Ka=\frac{[C_6H_5NH_2][H_3O^+]}{C_6H_5NH_3^+}[/tex]
Now, since the Kb of C6H5NH2 is 4.3 x 10^-10, its Ka is 2.326x10^-5 (Kw/Kb), we can also write:
[tex]2.326x10^{-5}=\frac{x^2}{0.517M}[/tex]
Whereas x is:
[tex]x=\sqrt{0.517*2.326x10^{-5}}\\\\x=3.47x10^-3[/tex]
Which also equals the concentration of hydrogen ions; therefore, the pH at the equivalence point is:
[tex]pH=-log(3.47x10^{-3})\\\\pH=2.46[/tex]
Regards!
what happened to Jodys
father
Answer:
Jody's father was bitten by a poisonous snakes name rattle snake
Where do most of the visible electromagnetic waves on Earth come from?
Question 3 options:
x-rays
the sun
radio waves
florescent lights
Answer:
the sun
Explanation:
hope this helps. :) brainlyest would be nice as well but it's ok if not, thank you!
Answer: the sun
Explanation:
In the combustion of gasoline, shown below, if 15.0 g of CO2 is produced, what volume of oxygen gas would be consumed? Assume STP. You must show your work.
Answer:
Depends on what you are burning. If it is carbon (ie coal), the answer is 15 (one liter CO2 for each liter of oxygen. Simply add a C onto an O2.) If you are burning octane, (C8H18), for each carbon you would you would have 1 1/8 H2Os and one CO2. To round off slightly (as I do not feel like getting out my calculator) we would have about twice as much oxygen tied up in CO2 as H20 (as there is only one O in H2O vs 2 in CO2). Therefore, in this case, it is ~10 l of CO2 for 15 l of oxygen. Propane will be different again, as will natural gas, etc.
Explanation:
B) Which of these is NEVER an example of freshwater? A) Pacific Ocean B) Okefenokee Swamp Mississippi River Lake Pontchartrain.
Answer:
Lake pontchartrain
Explanation:
Which is not true of the cell theory?
which is NOT true about the cell theory?
A:all living organisms are composed of cells
B:all cells have a nucleus, which acts like the brain of the cell
C:all cells come preexisting living cells
D:the cell is the most basic part of a living organism
You have a container which has the capacity to hold 3 L water. If it already has 2.25 L water in it, how much more water in mL can you still add to fill it completely?
When a solid turns into a liquid what is happening to the relationship between the forces?
what is the definition of drugs
Answer:
Drugs is a type of medication
Another meaning for it is something that makes you feel drunk such as wine, alcohol and as such that causes addiction.
The equilibrium constant, Kc, is calculated using molar concentrations. For gaseous reactions another form of the equilibrium constant, Kp, is calculated from partial pressures instead of concentrations. These two equilibrium constants are related by the equation Kp=Kc(RT)Δn where R=0.08206 L⋅atm/(K⋅mol), T is the absolute temperature, and Δn is the change in the number of moles of gas (sum moles products - sum moles reactants). For example, consider the reaction N2(g)+3H2(g)⇌2NH3(g) for which Δn=2−(1+3)=−2. Part A For the reaction 2A(g)+3B(g)⇌C(g) Kc = 63.2 at a temperature of 81 ∘C . Calculate the value of Kp. Express your answer numerically.
Answer:
Kp = 1.41 x 10⁻⁶
Explanation:
We have the chemical equation:
2 A(g) + 3 B(g)⇌ C(g)
In which A and B are the reactants and C is the product. We calculate first the change in the number of moles of gas (Δn or dn):
dn= (sum moles products - sum moles reactants)
= (moles C - (moles A + moles B))
= (1 - (2+3))
= 1 - 5
= -4
We have also the following data:
Kc = 63.2
T= 81∘C + 273 = 354 K
R = 0.082 L.atm/K.mol (it is a constant)
Thus, we introduce the data in the mathematical expression for the relation between Kp and Kc:
[tex]Kc = (RT)^{dn}[/tex]= (0.082 L.atm/K.mol x 354 K)⁻⁴ = 1.41 x 10⁻⁶
Which describes the proper way to use an eye wash station?
Keep your contact lenses in place.
Press on your eyelids firmly.
Rinse your eyes for fifteen minutes.
Call the paramedics for instructions.
Answer:
C
Explanation:
Rinsing your eyes thoroughly is the proper way to was your eyes out.
1. Take your contacts out as they can get stuck in your eye.
2. Don’t press on your eyes as you will just rub in the chemical substance more.
3. Can’t call the paramedics as you should rinse your eyes immediately.
If 4.52g of the precipitate is formed, how many grams of sodium chloride reacted?
The question is incomplete, the complete question is;
AgNO3(aq)+NaCl(aq)→AgCl(s)⏐↓+NaNO3(aq)
1- If 4.52g of the precipitate is formed, how many grams of sodium chloride reacted?
Answer:
1.8 g
Explanation:
Given the equation;
AgNO3(aq)+NaCl(aq)→AgCl(s)↓+NaNO3(aq)
We can see that the reaction is 1:1 Hence, 1 mole of sodium chloride yielded 1 mole of the precipitate(AgCl).
If this is so,
Number of moles of precipitate formed = 4.52g/143.32 g/mol
Number of moles of precipitate formed = 0.0315 moles
Hence, 0.0315 moles of precipitate was formed by 0.0315 moles of NaCl
Therefore;
Mass of NaCl reacted = 0.0315 moles * 58.5 g/mol = 1.8 g
How many grams of phosphorous is in the human skeleton if its average
weight is 11 kg and contains 58% of calcium phosphate (Ca3(PO4)2)?
Scientists examine fossils from three different animals. They determine that all three animals share similar structures and
record their observations as follows
• Animal A and animal B have somewhat similar structures
• Animal A and animal C have very similar structures
• Animal B and animal C have very similar structures
The scientists use the similarities to determine the order in which the fossils should appear in the fossil record. Based on the
scientists' observations, which order is the most reasonable?
ABC
ACB
С, В, А
В, А С
Answer:
C,B,A
Explanation:
C has the most similar structure
B has the second most similar structure
A has the least similair structure
Based on the scientists' observations, the order which is the most reasonable is C,B,A.
What are observations?Observations are defined as a set of statements or facts which are recorded while conducting an experiment.Observations are made through sensing changes in the variables of the experiment.
It is specifically defined as an act of knowing or recording the changes in the variables of the experiment.Recording observations holds importance as recording observations avoid the experiment to be repeated over and over again.
It is important to note down observations so that the testing of hypothesis is made easier.There are four types of observations .Observations need to be descriptive and must be written in complete sentences and should include all the numerical data of the experiment.
Learn more about observations,here:
https://brainly.com/question/14897780
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What is the noble gas configuration of Oganesson?
Answer:
5f14 6d10 7s2 7p6
Explanation:
This is because oganesson is a noble gas and element of group 18 which does not occur or is not produced naturally. It is produced in an experiment. It is a gas at room temperature and it has atomic number of 118. It is harmful and a radioactive gas due to it's radioactive properties and it is produced in small amound
how many grams are there in 3400 moles of tetranitrogen dicarbide?
Explanation:
molar mass of tetranitrogen dicarbide S4N4= 4×32+4×14
128+56
184 g/mol
no.of moles =given mass/ molar mass
3400= given mass / 184
3400×184 =given mass.
625600 g
Diffusion is the movement of water between the cell membrane.
O True
O False
it is true good friend chip chip cherrio
0.254g lead(ii)ethanoate, on adding excess K2CrO4 solution, gave 0.130g of lead(ii)chromate precipitate. what is the percentage composition of Pb in the organic salt? (O = 16, Cr = 52, Pb = 207).
Answer:
32.8%
Explanation:
All of the Pb⁺² species precipitated as lead(II) cromate, PbCrO₄ (we know this as excess K₂CrO₄ was used).
First we convert 0.130 g of PbCrO₄ into moles, using its molar mass:
0.130 g ÷ 323 g/mol = 4.02x10⁻⁴ mol PbCrO₄There's 1 Pb⁺² mol per PbCrO₄ mol, so in total 4.02x10⁻⁴ moles of Pb⁺² were in the ethanoate sample.
We convert those 4.02x10⁻⁴ moles of Pb into grams:
4.02x10⁻⁴ mol * 207 g/mol = 0.083 g PbFinally we calculate the percentage composition of Pb:
0.083 g Pb / 0.254 g salt * 100% = 32.8%name this structure
Answer:
The fourth one- bromo trifluoro methane
Explanation:
Answer:
D
Explanation:
I believe the answer is the 4th option, bromo-trifluoro-methane
Please help me thanks:)
Answer:
where it goes
Explanation:
Answer:
I didn't do the observation that the question said so I can't help sorry
Help me with this question
Answer:
your cool
Explanation:
owa owa owa owa owa bob
why is weather forecasting important to the people
Answer:
Weather forecasting is important to the people since it helps determine future climate expectations .
A cell is placed in a salt solution that has the same concentration as the inside of the cell. What will happen to the cell
A. The cell will contract
B. The cell will expand slightly
C. The cell will burst
D. The cell will remain the same size
By the way I had to ask again because I f forgot to put the answer choices
Answer:
B
Explanation:
If not B then its d
Answer:
D
Explanation:
This would be an isotonic solution. If a cell is placed in a solution of salt with the same concentration of salt in the cell, nothing will happen.
How does a computer's ability to perform so many calculations in a very short time affect how people communicate (pls help)
Answer:
A computer's ability to perform so many calculations in a very short time affects how people communicate by stopping them from talking actually. We no longer talk verbally. We don't go out and socialize, we always talk from the phone or text. We have lost our inner touch with talking.
Explanation:
3x + 4y - 3z) - (2x - 6y + 7z)
x + 10y - 10z
x + 10y - 10z
x -10y - 10z
Answer: x + 10y - 10z is the answer
Explanation:
How does the reactivity of nonmetals change as you move from left to right across the periodic table?
Answer:
Metallic character refers to the level of reactivity of a metal. Non-metallic character relates to the tendency to accept electrons during chemical reactions. Metallic tendency increases going down a group. Non-metallic tendency increases going from left to right across the periodic table.
Explanation:
I hope this helps :)
Answer:
Explanation:
Non metals increases in reactivity!
Four stereoisomers exist for 4-hexen-3-ol. Draw the structure of the isomer that has the Z configuration around the double bond and the R configuration at the chiral center.
Answer:
Following are the solution to the given question:
Explanation:
Please find the complete question and its graph file in the attachment file.
The isomer having Z specification from around dual connector as well as the chiral center S structure is:
[tex](3S,4Z)-4-Hexen-3-ol[/tex]
An 'H' atom has been at the level of 3rd carbon, and we need to change its configuration, through 'R' to 'S' by CIP notation (under contrast to -OH group).
Answer:
The double bond can have either the E or the Z configuration.
Each of these stereoisomers can exist in either the R or the S configuration at the chiral center for a total of four possible stereoisomers.
Hayley woke up to a hot and humid day but knows it is going to cool off later. What should she expect the weather to be like tonight?
Answer:
It will most likely rain because cool air cannot hold as much moisture as warm air.
Explanation:
I did the quiz !! :)
I really hope this helps!!!!!!!!!!!! :)
Is cheese melting on a hamburger conduction, convection, or radiation?
Answer:
convection
Explanation:
Answer:
Conduction
Explanation:
What is conduction? It is that heat is transferred from one particle of matter to another. It involves contact
A 0.00215-g sample of polystyrene, a polymer composed of carbon and hydrogen, produced 0.00726 g of CO2 and 0.00148 g of H2O in a combustion analysis. What is the empirical formula for polystyrene?
Answer:
CH
Explanation:
Polystyrene is composed only by C and H.
We can calculate the number of C moles contained in the original sample mass (0.00215 g), using the produced mass of CO₂:
0.00726 g CO₂ ÷ 44 g/mol = 1.65x10⁻⁴ mol CO₂As 1.65x10⁻⁴ moles of CO₂ were produced, in the polystyrene sample there were 1.65x10⁻⁴ moles of C.
Now we calculate how many moles of H₂O were produced:
0.00148 g H₂O ÷ 18 g/mol = 8.22x10⁻⁵ mol H₂OThe number of H moles produced is double the amount of H₂O moles, so in the polystyrene sample there were 1.64x10⁻⁴ moles of H.
The number of C and H moles are the same, this means the empirical formula is CH.