Answer:
d and e
Explanation:
We have 5 solutions with different molar concentrations, that is, the quotient between the number of moles of solute and the liters of solution. This can be expressed as mol/L or M. The most dilute would be the one having the less number of moles of solute per liters of solution, that is, solution d or e, which have the same concentration. If we order them from the most diluted to the most concentrated, we get:
d = e < a < b < c
In today's experiment, Solutions A and B are prepared as follows.
Solution A: Solution B:
2.0 mL of 3.00 x 10-4 M bromcresol green 2.0 mL of 3.00 x 10-4 M bromcresol green
5.0 mL of 1.60 M acetic acid (HAc) 2.0 mL of 0.160 M sodium acetate (NaAc)
2.0 mL of 0.200 M KCl diluted to a total volume of 50 mL
diluted to a total volume of 50 mL
What is the molarity of HAc in Solution A?
A. 6.4x 10-3
B. 3.20 x 10-4
C. 8.0 x 10-3
D. 0.160
E. 1.60
Answer:
D. 0.160
Explanation:
The solution A is obtained adding 2.0mL of a solution of bromocresol green, 5.0mL of 1.60M HAc and 2.0mL of a solution of KCl. The solution is diluted to 50mL
That means the HAc is diluted from 5.0mL to 50.0mL, that is:
50.0mL / 5.0mL = 10 times.
And the final concentration of HAc must be:
1.60M / 10 times =
0.160M
Right answer is:
D. 0.160Phenylephrine is a nasal decongestant and is the active ingredient in Sudafed, which contains phenylephrine hydrochloride (PEHCl).
a. True
b. False
Answer:
True
Explanation:
It is TRUE that Phenylephrine is a nasal decongestant and is the active ingredient in Sudafed, which contains phenylephrine hydrochloride (PEHCl).
Phenylephrine is considered a prescription formula that is used in the production of Sudafed. Due to its direct-acting sympathomimetic amine property, it is used as a significant ingredient in the formation of Sudafed, a drug usually prescribed for nasal decongestion from regular cold, upper respiratory allergies, hay fever, etc.
What are greenhouse gases?
structure of potassium trioxalatoaluminate(iii)?
Answer:
K3[Al(C2O4)3] is the answer
nitrogen dioxide does not rekindle a glowing splinter but support the combustion of carbon, phosphorus, lead etc, explain why given the equation of the reaction
Answer:
Nitrogen dioxide does not rekindle a glowing splinter becuase it is a not a very good oxidant. However, it will support the combustion of burning substances that are able to decompose it into nitrogen and oxygen gas.
NO₂ (g) ----> N₂ (g) + O₂
The oxygen then produced will go ahead to rekindle the glowing splinter.
Explanation:
Nitrogen dioxide isa reddish brown gas that is given when trioxiponitrate (v) salts, for example Lead (ii) trioxonitrate (v) of heavy metals are heated.
It is an mild oxidizing agent due to the presence of oxygen in the molecule of the compound.
It does not support combustion and does not burning air because of the inertnesss of the nitrogen atom. However, it will support the combustion of burning substances that are able to decompose it into nitrogen and oxygen gas.
For example, phosphorus is a very combustible material due to its low ignition temperature of 35°C. It catches fire spontaneously in air. Nitrogen dioxide is decomposed by burning phosphorus to nitrogen and oxygen. The oxygen produced supports further combustion of the burning phosphorus.
NO₂ (g) ----> N₂ (g) + O₂
Which of the following microorganisms is most likely to get its main source of nutrition from a host?
Bacteria
Parasite
T-cell
Virus
Answer:
A Parasite.
Explanation:
Viruses and bacteria can survive in most areas without a host. Parasites however need a host to survive. Some parasites include: tapeworm, roundworms, flukes, and protozoa.
If you get the question right i will give brainliest (HINT ITS NOT A)
Answer:
Explanation:
its b, i looked it up
Cells grouped together to make a specific part of the body of a plant or animal are called:
A. an organism
B. photosynthesis
C. a tissue
Help!!!
1.
Q: How does the distillation apparatus remove impurities from water?
Q: Why does water vapour condense in the condenser tube?
Q: As the boiling animation neared the end, what does the change in the proportion of particle types in the boiling flask indicate about the impurities?
Answer:
Q1) Distillation relies on evaporation to purify water
Explanation:
contaminated water is heated to form steam. inorganic compounds and large non-volatile organic molecules do not evaporate with the water and are left behind. The steam then cools and condenses to form purified water
What problems did Haber face? Think about equilibrium!
In your
explanation include the words nitrogen, hydrogen, ammonia, equilibrium, and
pressure.
State the number of protons, electrons and neutron
Answer:
You didn't show which element it is. The proton is the atomic number, the electron is the same number of protons, and the neutron is the atomic mass rounded to the nearest whole number minus the proton.
Explanation:
How many grams of KCl, are soluble in 100 g of water at 60 ºC?
a)15g
b)35g
c)45g
d)90g
45 g
the solubility of KCl in water at 60 degree c is 45.5g per 100g of water
Within an ecosystem,there are levels of organization. Which levels are missing from the diagram below?
Answer:
the missing levels are "population, community"
A 81 gram solution of silver nitrate contains
16 grams of AgNO3. What is the percent by
mass of silver nitrate in this solution?
Answer in units of %.
Answer:
19.75 %
Explanation:
The percent by mass of silver nitrate in the solution can be calculated using the following formula:
% AgNO₃ = Mass of AgNO₃ / Mass of solution * 100%As all the required data is already given by the problem, we can now proceed to calculate the percent by mass:
% AgNO₃ = 16 g / 81 g * 100 %% AgNO₃ = 19.75 %Select the correct answer. Which is true according to the law of conservation of energy? A. In a closed system, the total amount of energy in the universe keeps on changing. B. The supply of energy is limited, so it is essential to conserve it. C. In a closed system, energy can be created and destroyed. D. In a closed system, energy cannot be used faster than it is created. E. In a closed system, the total energy always remains constant.
in the image there is answer okk
Q1. Describe the term "Displacement reaction"
A 27 kg iron block initially at 375 C is quenched in an insulated tank that contains 130kg of water at 26 C. Assume the water that vaporizes during the process condenses back in the tank and the surroundings are at 12 C and 125 kPa. The specific heats of iron and water are 0.45 kJ/kgK and 4.18 kJ/kgK, respectively. a: Determine the final equilibrium temperature. b: Determine the entropy change of the combined system at the initial state. c: Determine the exergy of the combined system at the initial state. d: Determine the waste work potential during this process.
Solution :
a). Applying the energy balance,
[tex]$\Delta E_{sys}=E_{in}-E_{out}$[/tex]
[tex]$0=\Delta U$[/tex]
[tex]$0=(\Delta U)_{iron} + (\Delta U)_{water}$[/tex]
[tex]$0=[mc(T_f-T_i)_{iron}] + [mc(T_f-T_i)_{water}]$[/tex]
[tex]$0 = 27 \times 0.45 \times (T_f - 375) + 130 \times 4.18 \times (T_f-26)$[/tex]
[tex]$t_f=33.63^\circ C$[/tex]
b). The entropy change of iron.
[tex]$\Delta s_{iron} = mc \ln\left(\frac{T_f}{T_i} \right)$[/tex]
[tex]$ = 27 \times 0.45\ \ln\left(\frac{33.63 + 273}{375 + 273} \right)$[/tex]
= -9.09 kJ-K
Entropy change of water :
[tex]$\Delta s_{water} = mc \ \ln\left(\frac{T_f}{T_i} \right)$[/tex]
[tex]$ = 130 \times 4.18\ \ln\left(\frac{33.63 + 273}{26 + 273} \right)$[/tex]
= 10.76 kJ-K
So, the total entropy change during the process is :
[tex]$\Delta s_{tot} = \Delta s_{iron} + \Delta s_{water} $[/tex]
= -9.09 + 10.76
= 1.67 kJ-K
c). Exergy of the combined system at initial state,
[tex]$X=(U-U_{0}) - T_0(S-S_0)+P_0(V-V_0)$[/tex]
[tex]$X=mc (T-T_0) - T_0 \ mc \ \ln \left(\frac{T}{T_0} \right)+0$[/tex]
[tex]$X=mc\left((T-T_0)-T_0 \ ln \left(\frac{T}{T_0} \right)\right)$[/tex]
[tex]$X_{iron, i} = 27 \times 0.45\left(((375+273)-(12+273))-(12+273) \ln \frac{375+273}{12+273}\right)$[/tex]
[tex]$X_{iron, i} =63.94 \ kJ$[/tex]
[tex]$X_{water, i} = 130 \times 4.18\left(((26+273)-(12+273))-(12+273) \ln \frac{26+273}{12+273}\right)$[/tex]
[tex]$X_{water, i} =-13.22 \ kJ$[/tex]
Therefore, energy of the combined system at the initial state is
[tex]$X_{initial}=X_{iron,i} +X_{water, i}$[/tex]
= 63.94 -13.22
= 50.72 kJ
Similarly, Exergy of the combined system at initial state,
[tex]$X=(U_f-U_{0}) - T_0(S_f-S_0)+P_0(V_f-V_0)$[/tex]
[tex]$X=mc\left((T_f-T_0)-T_0 \ ln \left(\frac{T_f}{T_0} \right)\right)$[/tex]
[tex]$X_{iron, f} = 27 \times 0.45\left(((33.63+273)-(12+273))-(12+273) \ln \frac{33.63+273}{12+273}\right)$[/tex]
[tex]$X_{iron, f} = 216.39 \ kJ$[/tex]
[tex]$X_{water, f} = 130 \times 4.18\left(((33.63+273)-(12+273))-(12+273) \ln \frac{33.63+273}{12+273}\right)$[/tex]
[tex]$X_{water, f} =-9677.95\ kJ$[/tex]
Thus, energy or the combined system at the final state is :
[tex]$X_{final}=X_{iron,f} +X_{water, f$[/tex]
= 216.39 - 9677.95
= -9461.56 kJ
d). The wasted work
[tex]$X_{in} - X_{out}-X_{destroyed} = \Delta X_{sys}$[/tex]
[tex]$0-X_{destroyed} = $[/tex]
[tex]$X_{destroyed} = X_{initial} - X_{final}$[/tex]
= 50.72 + 9461.56
= 9512.22 kJ
What is the molarity of the solution formed by mixing 0.2 moles of NaOH with enough water to make 0.15 L of solution?
Answer: 0.5
Explanation:
A molecule or ion that donates the hydrogen in a hydrogen bond is a hydrogen bond donor.
a. True
b. False
Answer: The statement 'a molecule or ion that donates the hydrogen in a hydrogen bond is a hydrogen bond donor' is true.
Explanation:
A molecule or ion that donates hydrogen in a hydrogen bond is called a hydrogen donor.
For example, [tex]NH_{3} + H_{2}O \rightarrow NH^{+}_{4} + OH^{-}[/tex]
Here, [tex]NH_{3}[/tex] is donating the hydrogen ion to water molecule. Whereas water is accepting the hydrogen ion so water is a hydrogen bond acceptor. Therefore, hydrogen bond is formed by [tex]NH_{3}[/tex].
Thus, we can conclude that the statement 'a molecule or ion that donates the hydrogen in a hydrogen bond is a hydrogen bond donor' is true.
Two metals (Metal A and Metal B) are both exposed to a laser which emits photons that have a greater energy than the work function of both metals. Metal A has a smaller work function than Metal B. Therefore, The de Broglie wavelength of the electrons produced from metal A will be ____________ those from metal B.
The number of electrons produced from metal A will be ____________ the number produced from metal B.
Answer:
shorter than
equal to
Explanation:
Let us go back to the Einstein photoelectric equation;
KE = E - Wo
Where
KE = kinetic energy of the photoelectron
E = energy of the incident photon
Wo = work function of the metal
But KE = 1/2mv^2
Thus the velocity of the emitted photoelectron is determined by the kinetic energy of the emitted photoelectron.
Since the work function of metal A is smaller than that of metal B, the kinetic energy of photoelectrons emitted from metal A is greater than that of photoelectrons emitted from metal B . Therefore, the velocity of electrons from metal A is greater than those from metal B.
From de Broglie relation;
λ = h/mv
Where;
λ = de Broglie wavelength
h = Plank's constant
m = mass
v = velocity
Metal A producing electrons with greater velocity will lead to a shorter de Broglie wavelength compared to those from metal B.
The number of photoelectrons ejected is determined by the intensity of the photons and not the energy of the incident photons or the work function of the metals. Since the two metals are exposed to the the same laser, equal number of photoelectrons are produced for metals A and B.
How many molecules of H2O are equivalent to 98.2 g of H2O
Answer:
Demo Mole Quantities
58.5g NaCl(mol/58.5g)(6.02 x 1023/mol) = 6.02 x 1023 Na
+
Cl21 pre-1982 pennies (after 1982 pennies are mostly zinc with copper coating)
63.5g Cu( mol/ 63.5g)(6.02 x 1023/mol) = 6.02 x 1023 Cu
19.0g Al (mol/27.0g)(6.02 x 1023/mol) = 4.24 x 1023 Al
Explanation:
What is higher boiling point alkyne or alkyl halides??
Answer: alkyl halide
Explanation: brianlist please?
State Faraday's 2nd law of electrolysis
Answer:
[tex]{\huge\red{\fbox{{Faraday's 2nd Law of Electrolysis :-}}}}[/tex]
According to the second law of electrolysis, the same quantity of electricity will produce or dissolve chemically equivalent amounts of all the substances. This quantity of electricity is called Faraday (F). One Faraday is equal to 96487 coulombs per mole of electronic charges.
Match each phylum with the correct description
cnidarians
internal skeletons made of hardened plates
echinoderms
radial symmetry and stinging cells
arthropods
jointed body parts and an external skeleton
annelids
segmented body and closed circulatory
system
Answer:
:) Here
Explanation:
A reservoir is filled with 4 billion cubic feet of polluted water that initially contains 0.4% pollutant. Every day 400 million cubic feet of pure water enters the reservoir and the well-mixed solution flows out at the same rate. When will the pollutant concentration in the lake be reduced to 0.2%
Answer:
Thus, the pollutant concentration in lake will be reduced to 0.2% after 6.931471 days
Explanation:
From the information given:
A(t) = amount of pollutant for time (t)
A 4 billion cubic ft is the same as 4000 million cubic ft:
∴
The Initial amount of pollutant is [tex]A_o = (\dfrac{0.4}{100})\times 4000[/tex]
[tex]A_o = 16 \ million \ cubic \ feet[/tex]
However;
the pollutant rate (input) = 400 × 0 = 0
the pollutant rate (output) = [tex]400( \dfrac{A(t)} {4000})[/tex]
[tex]= 1( \dfrac{A(t)} {10})[/tex]
The net rate = [tex]A'(t) = 0 - 1( \dfrac{A(t)} {10})[/tex]
[tex]\implies A'(t) = - 1( \dfrac{A(t)} {10})[/tex]
[tex]\implies \dfrac{1}{A(t)}A'(t) = -(\dfrac{1}{10})[/tex]
[tex]\implies \int (\dfrac{1}{A(t)}A'(t) ) dt = \int -(\dfrac{1}{10}) dt[/tex]
[tex]\implies In (A(t)) = -(\dfrac{1}{10})t + c[/tex]
[tex]\implies A(t) = e^{-(\dfrac{1}{10})t+c}[/tex]
[tex]\implies A(t) = Ce^{-\dfrac{1}{10}^t}[/tex]
A(0) = 16
[tex]\implies Ce^{ -(1/20)^0} = 16 \\ \\ C = 16[/tex]
[tex]\implies A(t) = 16e^{(-1/10)t}[/tex]
[tex]0.2\% \ pollutant = (\dfrac{0.2}{100})*4000 =8 \ million \ cubic \ feet[/tex]
A(t) = 8
[tex]\implies 16e^{(-1/10)t}= 8 \\ \\ \implies e^{1/10)t} = 2 \\ \\ (\dfrac{1}{10} )^t = In(2) \\ \\ t = 10\ In(2) \\ \\ \mathbf{ t = 6.931471}[/tex]
5. True or False: If one thing in a food web is affected, it will only probably affect the organism that directly relies on it for energy. *
1 point
A. True
B. False
1. Which of the following is a mechanical mixture?
A. shampoo
B. chocolate chip cookie dough
C. tap water
D. air
The explosion of a bomb and the toxicity of a deadly poison are both chemical reactions.
•True
•False
Answer:
True
Explanation:
both are chemical, got it right on my test
what is the molar mass of barium hydroxide
Answer:
171.34 g/mol
Explanation:
Ba molar mass = 137.328 g/mol
O molar mass = 15.999 g/mol * 2 = 31.9980 g/mol
H molar mass = 1.008 g/mol * 2 = 2.0160 g/mol
137.328 + 31.9980 + 2.0160 = 171.3420 = 171.34 g/mol
Ca(OH)2 + 2HNO3 → Ca(NO3)2 + 2H2O
Answer: You have it right
Explanation:
you put the two on the H2O to make it 2H2O and A two on the HNO3 to make it 2HN03 To make it balanced, good job