Calculate the pH at the equivalence point for the titration of 0.200 M 0.200 M methylamine ( CH 3 NH 2 ) (CH3NH2) with 0.200 M HCl . 0.200 M HCl. The K b Kb of methylamine is 5.0 × 10 − 4 . 5.0×10−4. pH =
Answer:
pH = 5.85
Explanation:
The reaction of methylamine with HCl is:
CH₃NH₂ + HCl → CH₃NH₃⁺ + Cl⁻
As the titration was made with two solutions with the same molarity, the final concentration of the CH₃NH₃⁺ ion is 0.100M ([CH₃NH₃⁺] = 0.100M)
Then, the conjugate acid will be in equilibrium with water as follows:
CH₃NH₃⁺(aq) + H₂O(l) ⇄ CH₃NH₂(aq) + H₃O⁺(aq)
And the equilibrium constant, Ka, of this reaction is:
Kw/Kb = Ka = 1.0x10⁻¹⁴ / 5.0x10⁻⁴= 2x10⁻¹¹
2x10⁻¹¹ = [CH₃NH₂] [H₃O⁺] / [CH₃NH₃⁺]
As both CH₃NH₂ and H₃O⁺ comes from the same equilibrium we can say:
[CH₃NH₂] = [H₃O⁺] = X
And as we know [CH₃NH₃⁺] = 0.100M:
2x10⁻¹¹ = [X] [X] / [0.100M]
2x10⁻¹² = X²
X = 1.414x10⁻⁶M = [H₃O⁺]
And as pH= -log [H₃O⁺]
pH = 5.85What do scientists mean when they refer to population
population is the number of species living in a given area if this is regarding biology or earth studies :)
Classify the following as either an element, compound, homogeneous mixture or
heterogeneous mixture:
sodium chloride
Sodium chloride is the chemical name for salt and is composed of sodium and chlorine, so it is a compound.
13. An aerosol spray can of deodorant with a volume of 0.410 L contains 3.0 g of propane gas (CH3) as propellant. What is the pressure in the can at 20°C? VRT 3. og festa
Answer: The pressure in the can is 4.0 atm
Explanation:
According to ideal gas equation:
[tex]PV=nRT[/tex]
P = pressure of gas = ?
V = Volume of gas = 0.410 L
n = number of moles = [tex]\frac{\text {given mass}}{\text {Molar mass}}=\frac{3.0g}{44.1g/mol}=0.068mol[/tex]
R = gas constant =[tex]0.0821Latm/Kmol[/tex]
T =temperature =[tex]20^0C=(20+273)K=293K[/tex]
[tex]P=\frac{nRT}{V}[/tex]
[tex]P=\frac0.068mol\times 0.0820 L atm/K mol\times 293K}{0.410L}=4.0atm[/tex]
Thus the pressure in the can is 4.0 atm
Acidic hydrolysis involves the nucleophilic addition of water to the protonated amide.
a. True
b. False
Answer:
a
Explanation:
dont have to explain
Using the periodic table, choose the more reactive nonmetal.
Te or O
Answer:
answer is TE
Explanation:
Answer:
Tellurium is more reactive than Oxygen
ionization of sodium dichromate
Explanation:
this is the answer of your question .
hope it helped you
3.0L of a gas is at a temperature of 78c. Find the volume of the gas at standard temperature
Answer:
V=2.33361811192L or 2.3x10
Explanation:
Using Charles law V1/T1=V2/T2 Remember to convert celcius to kelvin by using the standard temperature 273.15K
3L/(78C+273.15)=V/273.15
What is the molality of a solution containing 18.2 g HCl and 250. g of water?
Answer:
m=2.0mol/kg
Explanation:
Hello there!
In this case, according to the formula to compute molality, which requires moles of solute (HCl) and kilograms of solvent (water), we first compute the moles of the former with its molar mass as shown below:
[tex]n=\frac{18.2g}{36.46g/mol}= 0.50mol[/tex]
And then the kilograms of water:
[tex]\frac{250.g}{1000g/kg} =0.250kg[/tex]
Finally, the molality turns out to be:
[tex]m=\frac{0.50mol}{0.250kg}\\\\m=2.0mol/kg[/tex]
Best regards!
What is Tiny grains that contain sperm call
Answer:
Pollen
Explanation:
Pollen is a powdery substance consisting of pollen grains which are male microgametophytes of seed plants, which produce male gametes (sperm cells).
You have three containers each of which is connected to a fourth empty container. Three of the containers contain pure gases. In the first container oxygen is at 2 atm, nitrogen at 4 atm is in the second container, and argon at 1 atm is in the third. When you open the valve and mix the gases in the forth container, what is the pressure, PT, in the forth container
Answer: The total pressure is 7 atm
Explanation:
According to Dalton's law, the total pressure is the sum of individual pressures.
[tex]p_{total}=p_A+p_B+p_C...[/tex]
Given : [tex]p_{total}[/tex] =total pressure of gases = ?
[tex]p_{O_2}[/tex] = partial pressure of oxygen = 2 atm
[tex]p_{N_2}[/tex] = partial pressure of nitrogen = 4 atm
[tex]p_{Ar}[/tex] = partial pressure of argon = 1 atm
putting in the values we get:
[tex]p_{total}=2atm+4atm+1atm[/tex]
[tex]p_{total}=7atm[/tex]
Thus the total pressure is 7 atm
A hot metal plate at 150°C has been placed in air at room temperature. Which event would most likely take place over the next few minutes?
Molecules in both the metal and the surrounding air will start moving at lower speeds.
Molecules in both the metal and the surrounding air will start moving at higher speeds.
The air molecules that are surrounding the metal will slow down, and the molecules in the metal will speed up.
The air molecules that are surrounding the metal will speed up, and the molecules in the metal will slow down.
Answer:
The air molecules that are surrounding the metal will speed up, and the molecules in the metal will slow down.
Explanation:
There will be a transfer of thermal energy (heat) from the hot metal plate to the surrounding air. This transfer of energy equates to a transfer of kinetic energy in the molecules. As the plate loses heat, the molecules in the plate will lose kinetic energy and slow down. As the surrounding air gains heat, the molecules will gain kinetic energy and speed up.
Answer: C
Explanation:
write the value of atmosphere pressure at sea level .
Answer:
standard sea- level pressure,by definition,equals 760 mm of Mercury,14.70 pounds per square inch, 1,013.25x10³ dynes per square centimetre, 1,013.25 millibars,one standard atmosphere,or 101.325 kilopascale
Here's your answerl hope it's helpful for u....
Predict the product of this reaction
Al(s) + N2(g)—->
Name the following straight-chain
alkane.
CH3CH2CH2CH3
Answer:
[tex]\huge\boxed{BUTANE}[/tex]
Explanation:
Since it is alkane, The suffix used will be "-ane".
Prefix for 4 carbons => "but-"
Hence, the name:
BUTANE
[tex]\rule[225]{225}{2}[/tex]
Hope this helped!
~AH1807
Which general equation represents an endothermic reaction?
A. reactants - energy - products + energy
B. reactants
products + energy
C. reactants + products - energy
D. reactants + energy
products
Explanation:
The general equation for an endothermic reaction is: Reactants + Energy → Products.
Hope it helps :)❤
The equation represents an endothermic reaction is reactants + energy
products.
What is an endothermic reaction?
Endothermic reactions are chemical reactions in which the reactants soak up warm strength from the surroundings to form products.
net energy is not released.heat is not evolved with the product.heat is required to start the reaction.increase with the increase in temperature.decrease with a decrease in temperature.Learn more about the endothermic reaction here:-https://brainly.com/question/6506846
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How to balance NaOH+CO2=Na2CO3+H2O by algebraic method?
anyone help with the percent yield questions?
Answer:
oof this is way to hard sry man
Explanation:
What is the pressure inside a balloon that contains 10.0 g of helium at 25.0°C when the helium occupies a volume of 56.0 L?
A 10.9 atm
B 0.916 atm
C 11.1 atm
D 1.09 atm
Explanation is in the file
tinyurl.com/wpazsebu
How many grams of ( S ) - 1 - chloro - 4 - ethyl - 2 - methylhexane and triphenylphosphine would you need to create 4 . 1 5g of ( S ) - 1 - chloro - 4 - ethyl - 2 - methyl triphenylphosphonium assuming an 8 1 % yield for the reaction?
Answer:
Explanation:
The standard molar mass is:
For (S )-1-chloro-4-ethyl-2-methylhexane = 162.5 g/mol
For triphenylphosphine = 262 g/mol
For ( S )-1-chloro-4-ethyl-2-methyl triphenylphosphonium = 424.5 g/mol
The mass required for 81% yield = [tex]\dfrac{81}{100} \times Theoretical \ yield = 4.15 g[/tex]
Theoretical yield = [tex]\dfrac{4.15}{0.81}[/tex]
= 5.1235 g
thus, since 424.5 g yield produce from 162.5 g
∴
5.1235 g yield will produce = [tex]\dfrac{162.5}{424.5}\times 5.1235 \ g[/tex]
= 1.9613 g of alkyl halide (-chloro) required.
Also, since 424.5 g yield produce from 262 g phosphine
∴
5.1235 g yield will produce = [tex]\dfrac{262}{424.5}\times 5.1235 \ g[/tex]
= 3.1622 g of triphenylphosphine required.
A certain metal M forms a soluble nitrate salt M NO Suppose the left half cell of a galvanic cell apparatus is filled with a 3.00 mM solution of M(NO) and the right half cell with a 3.00 M solution of the same substance. Electrodes made of M are dipped into both solutions and a voltmeter is connected between them. The temperature of the apparatus is held constant at 20.0 °C.
1. Which electrode will be positive? What voltage will the voltmeter show?
a. left
b. right
2. Assume its positive lead is connected to the positive electrode. Be sure your answer has a unit symbol, if necessary, and round it to 2 significant digits.
Answer:
Explanation:
From the information given:
left half-cell = 3.00 mM M(NO)
right half-cell = 3.00 M M(NO)
Since the electrode are the same in both cells, then the concentration for the cell are also the same.
Negative electrode = Anode = lower concentration = 3.00 mM
Positive electrode = cathode = higher concentration = 3.00 M
Thus, right half cell will be postive electrode.
To determine the concentration cell:
[tex]Ecell =\Big( \dfrac{2.303\times R\times T}{nF} \Big)log\Big(\dfrac{[cathode]}{[anode]}\Big)[/tex]
SInce [Cathode] > [anode],
[tex]R = 8.314 J/K/mol, \\ \\ T = 273+20 = 293 K \\ \\ Faraday's constant (F)= 96500 C/mol[/tex]
n = 3
[tex]Ecell ={ \dfrac{2.303\times 8.314\times 293 }{(3\times 96500)}} log\dfrac{3}{0.003}[/tex]
[tex]\mathbf{E_{cell} = 0.0582 V } \\ \\ \mathbf{E_{cell} = 0.06 V}[/tex]
Would you rather wear
Socks in sandals or wear shoes without socks
Answer:
i always wear shoes without socks
Explanation:
You have 281 kilojoules how many kilocalories is it need to know ASAP
Explain what method you would use to obtain
Petrol (boiling point 20
60 C) from a mature of petrol and kerosene (boiling point 180 220 C)
Answer:
Fractional distillation of crude oil in laboratory
Explanation:
In general, we can sort them according to their boiling point.
We should first place a ball of mineral wool soaked with petroleum into a boiling tube and heat it with a Bunsen flame. At the beginning of the experiment, heat the mineral with a gentle flame, and then more strongly later. The fraction with a lower boiling range will distil out first. Since petrol is quite volatile, it should be condensed by cooling with water or an ice-water bath.
Petrol will be collected first, as it has a lower boiling point than kerosene. It will turn into vapour and condense again in the receive tub in the beaker.
An unknown concentration of sodium thiosulfate, Na2S2O3, is used to titrate a standardized solution of KIO3 with excess KI present. Suppose 15.65 mL of the Na2S2O3 solution is required to titrate the iodine formed from 21.55 mL of 0.0131 M KIO3. What is the molarity of the Na2S2O3 solution
Answer: The molarity of [tex]Na_2S_2O_3[/tex] is 0.108 M
Explanation:
[tex]KIO_3+5KI+3H_2SO_4\rightarrow 3K_2SO_4+3H_2O+3I_2[/tex]
[tex]2Na_2S_2O_3+I_2\rightarrow Na_2S_4O_6+2NaI[/tex]
To calculate the number of moles for given molarity, we use the equation:
[tex]\text{Molarity of the solution}=\frac{\text{Moles of solute}}{\text{Volume of solution (in L)}}[/tex]
[tex]\text{Moles of }KIO_3=\frac{0.0131mol/L\times 21.55}{1000}=2.8\times 10^{-4}mol[/tex]
1 mole of [tex]KIO_3[/tex] produces = 3 moles of [tex]I_2[/tex]
[tex]2.8\times 10^{-4}[/tex] moles of [tex]KIO_3[/tex] produces = [tex]\frac{3}{1}\times 2.8\times 10^{-4}=8.4\times 10^{-4}[/tex] moles of [tex]I_2[/tex]
Now 1 mole of [tex]I_2[/tex] uses = 2 moles of [tex]Na_2S_2O_3[/tex]
[tex]8.4\times 10^{-4}[/tex] moles of [tex]I_2[/tex] uses = [tex]\frac{2}{1}\times 8.4\times 10^{-4}=1.69\times 10^{-3}[/tex] moles of [tex]Na_2S_2O_3[/tex]
[tex]\text{Molarity of the solution}=\frac{\text{Moles of solute}}{\text{Volume of solution in L}}=\frac{1.69\times 10^{-3}\times 1000}{15.65}=0.108M[/tex]
The molarity of [tex]Na_2S_2O_3[/tex] is 0.108 M
How many moles of water will be produced from the reactions 3.25 moles of hydrochloric acid react with excess calcium hydroxide
Answer:
3.25 moles of H2O
Explanation:
We'll begin by writing the balanced equation for the reaction. This is given below:
2HCl + Ca(OH)2 —> CaCl2 +2H2O
Now, we can obtain the number of mole H2O produced from the reaction as follow:
From the balanced equation above,
2 moles of HCl reacted to produce 2 moles of H2O.
Therefore, 3.25 moles of HCl will also react to produce 3.25 moles of H2O.
Therefore, 3.25 moles of H2O were produced from the reaction.
im not sure if it is a molecule or an atom
Answer:
the first one
Explanation:
I looked it up:P
Only the 2nd answer is right, uncheck the 1st one
Explanation:
If we had a chemical formula like [tex]3(O_{2} )[/tex] the 3 means there are 3 molecules of [tex]O_{2}[/tex]. The 2 means there are two atoms of oxygen in each molecule.
calculate the number of moles of chloride needed to form 14.0 moles of iron lll chloride. 2Fe+3Cl2=2FeCl3 ?
Explanation:
The reaction is
2Fe+3Cl2
→2FeCl3
So the mol ratio
Cl2÷FeCl3=3÷2
So for 14 mols of F
eCl3
we need 32×14=21
mols of Cl2
What is the correct chemical name for N3H4
Answer:
Molar mass of N3H4 name is 84.0761 g/mol
Convert between N3H4Na(CH3) weight and moles
The chemical name for the formula N₃H₄ is Trinitrogen Tetrahydride
How a chemical compound is named ?The first element is named by simple using the name of the element. The second element is named by taking the stem of the element name and adding the suffix -ideThe element that is less electronegative is written first ,there are exceptions like , Carbon is always first in a formula and hydrogen is after nitrogen in a formula such as NH3 . The sequence of common nonmetals in binary compound is
C , P , N , H , S , I , Br , Cl , O , F .
So Now for N₃ = Tri Nitogen
and for H₄ = Tetra Hydride
Therefore the chemical name is Trinitogen Tetrahydride.
To know more about Chemical Compound
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depression How does a person get the disorder (causes) - it might be genetic, the result of an injury, or possibly the factors are unknown.
Answer:
There's no single cause of depression. It can occur for a variety of reasons and it has many different triggers. For some people, an upsetting or stressful life event, such as bereavement, divorce, illness, redundancy and job or money worries, can be the cause. Different causes can often combine to trigger depression. For example, you may feel low after being ill and then experience a traumatic event, such as a bereavement, which brings on depression.