Answer:
Ni2+ is reduced at the cathode.
The anode reaction could be Cr -> Cr3+ + 3e-
As the cell runs, anions will migrate from the Ni2+|Ni compartment to the other compartment.
Explanation:
As we know, in a galvanic cell, oxidation occurs at the anode and reduction occurs at the cathode. Hence at the cathode, nickel is reduced as follows;
Ni^2+(aq) + 2e ----> Ni(s)
Considering the reduction potential of the Ni2+ | Ni half cell (-0.25 V) and that of the Cr3+/Cr half cell (-0.74 V), the later has a more negative reduction potential and will most likely serve as the anode of the galvanic cell.
Lastly, the reduction of Ni^2+ leads to a build up of anions in the cathode compartment. To maintain neutrality in the cell, some anions migrate to the other compartment.
A 6.8 L sample of gas is collected at a pressure of 0.91 atm. What will the Volume of the gas occupy at 1.0 atm if the temperature remains constant?
Answer:
Explanation:
V1*P1= V2*P2
6.8L*0.91atm=1.0atm*x
x=6.188 L
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
HELPP! pls
Consider the following reaction: _2_ Al + _6_ HBr → _2_ AlBr3 + _3_ H2
When 3.22 moles of Al reacts with 4.96 moles of HBr, how many moles of H2 are formed?
What is the limiting reactant?
What is the excess reactant?
Answer:
"2.48 mole" of H₂ are formed. A further explanation is provided below.
Explanation:
The given values are:
Mole of Al,
= 3.22 mole
Mole of HBr,
= 4.96 mole
Now,
(a)
The number of mole of H₂ are:
⇒ [tex]\frac{Mole \ of \ H_2}{3} =\frac{Mole \ of HBr}{6}[/tex]
or,
⇒ [tex]Mole \ of \ H_2=\frac{1}{2}\times Mole \ of \ HBr[/tex]
⇒ [tex]=\frac{1}{2}\times 4.96[/tex]
⇒ [tex]=2.48 \ mole[/tex]
(b)
The limiting reactant is:
= [tex]HBr[/tex]
(c)
The excess reactant is:
= [tex]Al[/tex]
Calculate the osmotic pressure of 5 % glucose solution and the osmotic pressure of 0.2 %, 0.9 % and 10 % sodium chloride solutions on the base of Van’t Hoff’s law (d = 1.1 g/ml for 10 % NaCl).
Based on Van't Hoff's law, the osmotic pressure of 5% glucose solution with 0.2%, 0.9%, and 10% sodium chloride solutions is 0821 liter atm K1mol1).
What is the osmotic pressure Van t Hoff law?Boyle, Van't Hoff The rule of solution: In a delute solution, the osmotic pressure () is directly proportional to the molar concentration (C) or inversely proportional to the volume (V) of the solution at constant temperature. Reason: C but C = Vn.
What does class 12 osmotic pressure formula mean?Pi=iMRT is the formula for osmotic pressure. The osmotic pressure increases with a solution's concentration (M) or temperature (T).
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starting with calcium chloride describe how one can prepare calcium carbonate
0.0075mole of calcium trioxocrabonate IV is added to 0.015mole of a solution of hydrochloric acid .the volume of gas evolved at stp is
Answer:
1mole of gas at STP = 22.4dm3
0.0075 mole of CaCO3 = xdm3
cross multiply;
where 22.4dm3 = 22400cm3
x * 1 = 0.0075 * 22400 → 168cm3
the gas CO2 which evolved was gotten from CaCO3 so we use the number of moles of CaCO3 only
These are specially built to prevent waste chemicals from moving into the soil. As rainwater or groundwater moves through solid waste, it can dissolve or corrode some items. Plastic liners and compacted clay are used to prevent these solutions from entering the soil and the groundwater.
a
Sewage Treatment Facility
Sanitary landfill
c
Landfill
d
Effluent
Answer:
sanitary landfill is the answer
Two clear solutions are placed in separate beakers. The first solution has a pH = 4, and the pH of the second solution is unknown.
If the two solutions are mixed and the resulting solution has a pH = 7, describe the second solution.
A) The second solution has a higher pH level than the first solution. It has a
pH that is weaker but still neutralized the first solution. It also has a higher
concentration of hydronium ions compared to the first solution.
B) The pH of the second solution is higher than the pH of the first solution. It
is also acidic and, therefore, has a higher concentration of hydroxide ions
compared to the first solution.
C) The second solution has a basic pH level. It was strong enough to
neutralize the first solution. It also has a higher concentration of hydroxide
ions compared to the first solution.
D) The second solution has and equivalent number of hydroxide and
hydronium ions. It has a pH level that is higher (stronger) than the first
solution.
Answer:
C.
Explanation:
When the pH is 7 there is equal amount of H+ and OH so the solution added must be strong enough to nuetralize the acid. So option A is out B is wrong because adding a acidic solution to an acidic solution wont nuetralize it, D is wrong because if the 2 solution was already equal in both it would essentaly be water. ALthough water would raise the pH it would not nuetralize it to a even 7.
Calculate the molecular weight of chalk.Step by step
Answer:
100 g/mol
Explanation:
The chemical formula of chalk is CaCO3
So
1x Ca =40
1x C = 12
Ox 3 = 16
Meaning it has a molar mass of 100
Why is only a small amount of the energy stored in food available to the next organism in a food web or chain?
There are more producers than consumers.
There are fewer top consumers
Primary and secondary consumers compete for their food.
Most energy is used for life or released as heat before the organism is eaten.
Answer:
There is only a small amount of energy stored in food for the next organism because the other organisms have to share their food with other animals which will limit the amount of food if that makes sense. (Basically the primary and secondary consumers competing each other for food)
Explanation:
Answer:
There is only a small amount of energy stored in food for the next organism because the other organisms have to share their food with other animals which will limit the amount of food if that makes sense. (Basically the primary and secondary consumers competing each other for food)
Explanation:
3.
Find the kinetic energy of a 20,000-kg truck moving at 110 km/h (leave your answer in standard form
Answer:
9,339,136 J
Explanation:
Convert km/hr to m/s:
(110km/s)(1000m/km)(1hr/60min)(1min/60s) = 30.56m/s
KE = (1/2)mv^2 = (1/2)(20,000kg)(30.56m/s)^2 = 9,339,136 J
2. A small block of a metal with a mass of 223.1 grams when
submerged in a beaker containing water, the water level rises to
150.0 mL as shown in the figure here. If the density of the metal
block is 7.41 g/cm³ at 22°C, then what was the original water level
in the beaker?
Water leve
150 mL
The volume of the metal block can be calculated using the density and mass of the block is 30.0 cm³
What is metal block?A metal block is a solid piece of metal that is typically used for machining and other industrial applications. It is usually made from aluminum, steel, or other metals, and can be machined into a variety of shapes and sizes depending on the application. Metal blocks are also used for casting, forging, and other manufacturing processes. Metal blocks may also be used for decorative purposes, such as sculpture or engraving. They are also used in jewelry making and engraving, as well as in medical and dental applications.
The volume of the metal block can be calculated using the density and mass of the block:
Volume = Mass/Density = 223.1 g/7.41 g/cm³ = 30.0 cm³
Since the metal block was submerged in the water, the volume of the block will be added to the volume of water in the beaker. Therefore, the original water level in the beaker can be calculated using the following equation:
Original Water Level = 150 mL + (30.0 cm³/1000 cm³/mL) = 180.0 mL
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How many moles are in 18.3 grams of Carbon?
Answer:
1.5236414197340638
The graph represents the amount of energy in the
reactants and products of a chemical reaction.
If total energy is conserved, which statement
explains why the energy of the reactants does not
equal the energy of the products?
Energy
Energy of Energy of
Reactants Products
A.
The reaction is exothermic
B. The reaction is endothermic.
C. The reaction requires a catalyst.
D
The reaction has a low activation energy.
Answer: The correct answer is in an exothermic reaction the energy of the product is less than the energy of the reactants.
Explanation: got it
The energy of reactants is not equal to that of products as the reaction is an exothermic reaction.
What is an exothermic reaction?
An exothermic reaction is defined as a chemical reaction which involves release of energy in the form of light,heat .In these reactions, energy is transferred from system to surroundings rather than taking energy from surroundings into system as in endothermic reactions.
In an exothermic reaction,change in enthalpy is negative.Therefore, it can be inferred that net amount of energy which is required to start the exothermic reaction is less than the net amount which is released by the reaction.
Examples of exothermic reactions are combustion reactions, detonation of nitroglycerin , neutralization reactions and nuclear fission.
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What is the [H+] if [OH-] = 1 x 10-5 M?
why does water wet glass and not mercury
Can someone help me with this pls
Answer:
i think the correct answer is A
Manganese is a transition metal. Consider the isotope: Mn-53. How many protons are in an atom of Mn-53 if the atom has a charge of 5?
Answer:
25
Explanation:
Isotopes of an element are the same element with different mass numbers but the same atomic number or the number of protons.
we know that in a balanced atom
Number of electrons = Number of protons = Atomic number
Atomic number (z) of manganese = 25
For Mn+5, the number of protons remains the same = 25
However, the number of electrons on Mn+5 = 21
Answer: 25
Explanation:
Q1. Describe the term "Displacement reaction"
Given: Mg3N2 + 3 K2O → 3 MgO + 2 K3N
If 14 moles of potassium oxide, K2O, reacts, how many grams of potassium nitride, K3N, will be made? Show work
Explanation:
14 moles of potassium oxide, K2O, reacts, how many grams of potassium nitride, K3N, will be made? Show work
Which of the following statements is true?
A Protons are positively charged and have a mass of 1 amu.
B Electrons are negatively charged and have a mass of 1 amu
C. The nucleus of an atom is positively charged and never has a mass of 1 amu,
D. Neutrons are negatively charged and have a mass of 1 amu,
Answer: Correct option is (A)
Explanation:
Protons carry a single positive charge that have a mass of one approximately one atomic mass unit.
Answer:
B: its positively charged of 1 or 3 amu
Explanation:
Hope it works!!
HELP PLEASEUse the molar volume of a gas at SATP to determine the
following values at SATP:
(a) the amount of nitrogen in 44.8 L of pure gas
(b) the volume (in litres) of 4.8 mol of propane gas, C3H,(g)
(c) the mass of carbon dioxide in 34.6 L of carbon dioxide
gas, CO₂(g)
(d) the volume (in mL) of 1250 g of methane, CH₂(g)
(e) the amount of oxygen in 36.5 L of 02 gas
The most common example is the molar volume of a gas at standard temperature and pressure (STP), which is equal to 22.4 L for 1 mole of any ideal gas at 273.15 K and 1 atm of pressure.
What are the applications of the Ideal Gas Law- Molar Volume?Stoichiometry refers to the quantitative relationship between reactants and products. Calculating the quantities of reactants needed to make a given quantity of products, or the quantities of products resulting from a given quantity of reactants, is required in stoichiometric problems. Gas laws must be taken into account for the calculation if one or more reactants or products in a chemical reaction are gases. The findings of ideal gas law applications are often accurate to within 5%. We go over a few key ideas that are crucial for solving Stoichiometry Problems involving Gases in the sections below.
Stoichiometry and gas laws both rely on the mole notion as their foundation. A mole is an exact measurement of a substance. Based on the quantity of identities, a mole is a unit (i.e. atoms, molecules, ions, or particles). The number of identities in a mole of anything is equal to the number of atoms in exactly 12 grams of carbon-12, the most common isotope of carbon.
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Which of the following best represents the structure of an amino acid in basic solution (pH = 11)?
Answer:
Explanation:
In basic solution (pH = 11), an amino acid typically exists in its zwitterionic form. This means that the amino acid has both a positive and a negative charge, due to the presence of both a basic amino group (-NH2) and an acidic carboxyl group (-COOH).
The structure of an amino acid in basic solution (pH = 11) can be represented as follows:
The central carbon atom (also known as the alpha carbon) is bonded to a hydrogen atom, an amino group (-NH2), a carboxyl group (-COOH), and a side chain R group.
The amino group is positively charged due to the loss of a proton (H+).
The carboxyl group is negatively charged due to the gain of a proton (H+).
Overall, the amino acid has a net charge of zero, due to the equal and opposite charges of the amino and carboxyl groups. This is known as the zwitterionic form of the amino acid.
Here is a visual representation of the structure of an amino acid in basic solution (pH = 11):
H |
N-C-COOH
|
R
Regenerate response
A GC analysis of a oil containing the unknown diene produced a chromatogram with 3 distinct peaks. From the determination of peak area, you find that the percent compositions represented by the peaks are: peak A is 26.66 percent, peak B is 60 percent, and peak C is 13.33 percent. If the largest peak in the chromatogram corresponds to the diene, how many moles of diene are in the crude oil
Answer:
0.011 moles of diene are in the crude oil
Explanation:
The mass of the oil is 2.5g and the M.W. of the diene is 136g/mol
The largest peak is the peak that has the higher percent concentration: That is the peak B with 60% by mass.
Knowing this we can find the mass of the diene using its percentage and with the mass and the molecular weight we can find its moles:
Mass Diene:
2.5g Oil * (60g Diene / 100g Oil) = 1.5g Diene are in the oil
Moles:
1.5g Diene * (1mol / 136g) =
0.011 moles of diene are in the crude oil
The following statements are either true or false. Read each sentences carefully, then write TRUE faLSE
1. A force cannot be seen
2. A force cannot be felt.
3. A force always causes things to move
When an object is at rest, no gravitational force is acting on it
5 Gravitational force pulls all things downward
5. Mass and weight are the same quantities
7. All objects on Earth have weight
8 Some forces are useful to people
9. Gravity makes it easy for a person to ride a bicycle up
10. Weight is measured in grams (R) and kilograms
1) T
2) F
3) F
4) F
5) T
6) F
7) T
8) T
9) F
10) ...T... grams are usually in lowercase g
How to solve this problem? I am stuck
The functional group of molecules as follows :
Molecule 1. is aldehyde and ketone, Molecule 2 is acid and thio, Molecule 3 is acid and amide, Molecule 4 is alcohol and ether, Molecule 5 is Alcohol and acid. The image attached below show the functional group and molecules are labeled.
What is polar compound ?The polar compounds are those compound having different positive and negative charge, therefore the bonding with atoms such as nitrogen, oxygen, or sulfur.
A buffer is a solution the can control the pH change along with the addition of an acidic or basic substance. It is able to neutralize small amounts of added acid or base, So it maintains the pH of the solution. This is important to maintain pH ranges.
Thus, Molecule 1. is aldehyde and ketone, Molecule 2 is acid and thio, Molecule 3 is acid and amide, Molecule 4 is alcohol and ether, Molecule 5 is Alcohol and acid.
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А
A and B are forces acting on a falling object. Which
force, A or B, represents gravity in the diagram?
Force 1
is gravity because it attracts the ball
to the ground.
B
Ground
Answer:
Force B
Explanation:
Gravity pulls "down" :D
Hoped this helped!
Have a nice day!
Why Zinc is not really considered as member of the transition metals?
The definition of a transition metal is that it must have an incompleted sub-level in one or more of its oxidation states. As zinc has a completed sub-level at all oxidative states, so it can't be considered a transition metal.
What is the hybridization of all the atoms (other than hydrogen) in each of the following species?
Drag the appropriate items to their respective bins.
The hybridization of C in HCN is sp because, carbon is triple bonded to the nitrogen. Hybridization of N in HCN is also sp. Hybridization of nitrogen in NH₄ is sp³.
What is hybridization?When tow atoms combines to form a molecules, the energy of individual atomic orbitals redistribute to form hybrid orbitals of equivalent energy. The type of hybridization s based on the on the involvement of s, p or d orbitals of the atom.
In HCN, carbon is triple bonded to nitrogen. Here, both s and p orbital contribution is 50%. Hence, both C and N in HCN in sp hybridized.
In NH₄, the nitrogen is sigma bonded to each hydrogen and the hybridization of N is sp³ here since, 3 p orbitals of nitrogen and one s orbital are involved.
In CH₃-, C is sp² hybridized and in CH₃⁺ , C is sp³ hybridized. The C in C(CH₃)₄ is also sp³ hybridized where carbon involves sigma bonds with the methyl groups.
N in NH₃ is sp³ hybridized. Oxygen in water is sp² hybridized. When water abstracts one more proton forming H₃O⁺ , oxygen forms sp³ hybridized orbitals.
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If you get the question right i will give brainliest (HINT ITS NOT A)
Answer:
Explanation:
its b, i looked it up