Answer:
[tex]K=3.2[/tex]
Explanation:
Hello,
In this case, for the given equilibrium, we write the law of mass action:
[tex]K=\frac{[PCl_3][Cl_2]}{[PCl_5]}[/tex]
Next, in terms of the change [tex]x[/tex] due to the reaction extent (ICE procedure):
[tex]K=\frac{x*x}{1M-x}[/tex]
Clearly, the initial concentration phosphorous pentachloride is 1 M (one mole per litre), therefore, since the equilibrium concentration is 0.2 M (same volume) we can compute [tex]x[/tex]:
[tex]x=1M-0.2M=0.8M[/tex]
Thus, we compute the equilibrium constant:
[tex]K=\frac{0.8*0.8}{0.2} \\\\K=3.2[/tex]
Regards.
PLEASE HELPPPP!!!
diameter & volume question
Answer:
65450 in^3
Explanation:
Someone deleted my old answer
In the Hall-Heroult process, a large electric current is passed through a solution of aluminum oxide dissolved in molten cryolite , resulting in the reduction of the to pure aluminum. Suppose a current of is passed through a Hall-Heroult cell for seconds. Calculate the mass of pure aluminum produced. Round your answer to significant digits. Also, be sure your answer contains a unit symbol.
The given question incomplete, the complete question is:
In the Hall-Heroult process, a large electric current is passed through a solution of aluminum oxide (Al,03) dissolved in molten cryolite (Na, Alts).re in the reduction of the Al, o, to pure aluminum. Suppose a current of 1800. A is passed through a Hall-Heroult cell for 37.0 seconds. Calculate the mass of pure aluminum produced Be sure your answer has a unit symbol and the correct number of significant digits.
Answer:
The correct answer is 6.2114 grams.
Explanation:
Based on the given question, the value of current or I have given is 1800 amperes, the time given is 37 seconds, and there is a need to find the mass of the pure aluminum generated in the process. Mass or weight can be determined by using Faraday's first law equation, that is, w = MIt/nF.
Here, M is the atomic mass, w is the weight of the substance deposited, t is time, I is current, n is the number of moles of the electron, and F is the Faraday's constant, which is 96500 C. In the process mentioned in the question, aluminum oxide is reduced to give rise to pure aluminum, and in the process 3 electrons are gained. So, the value of n will be 3. The M or the atomic mass of Al is 27 gm per mole. Now putting the values in the equation we get,
w = 27*1800*37 / 3*96500
w = 1798200 / 289500
w = 6.2114 grams
Hence, pure aluminum produced in the process is 6.2114 grams.
Draw a chair conformation for cis-1-bromo-2,4-dimethylcyclohexane showing equatorial and axial positions at the carbon atoms bearing the substituents (all substituents are at cis configuration) g
Answer:
See attachment.
Explanation:
Mono-substituted cyclohexanes are more stable with their substituents in an equatorial position. However, with poly-substituted cyclohexanes, the situation is more complex since the steric effects of all substituents have to be taken into account. In this case, you can see that the interconversion is shifted towards the conformation in the bottom because there is less tension between the substituents.
Each of these geometric shapes has a different number of sides. Arrange the shapes in order from the shape with the greatest number of sides to the shape with the fewest number of sides. Rank these shapes from greatest to fewest number of sides. To rank items as equivalent, overlap them.
triangle , square, rectangle, octagon, hexagon, pentagon
1. Octagon (8 sides)
2. Hexagon (6 sides)
3. Pentagon (5 sides)
4. Square/Rectangle (4 sides)
5. Triangle (3 sides)
Hope this helps :)
There is a container on the lab bench containing some unknown chemical. You should:
a. Dump it, wash the glassware. Some people are slobs.
b. Move it out of the way in case it is dangerous. Otherwise, not your problem.
c. Leave it. The rightful owner will claim it eventually.
d. Tell your lab supervisor.
Answer:
D
Explanation:
Your supervisor is in charge of you so therefore you must always tell your supervisor first.
Answer:
C.
Explanation:
Because you might get hurt, could be dangerous.
A maple tree could be studied in many fields of science. What aspect of a maple tree might be studied in chemistry
Answer:
botany because a maple tree is a plant
Explanation:
The active ingredient in many commercial liquid bleaches is sodium hypochlorite. The bottle lists the percentage of sodium hypochlorite as 6.0%. If the density of commercial bleach is 1.084 g/mL, how many mL of 0.150 M sodium thiosulfate is required to reach the end point in a titration similar to the one performed in this experiment, if a student analyzed a 2.0 mL sample of bleach.
Answer:
23.3mL of 0.150M sodium thiosulfate
Explanation:
The net reaction of sodium hypochlorite (NaClO) with sodium thiosulfate (Na₂S₂O₃) is:
NaClO + 2 Na₂S₂O₃ + 2H₃O⁺ → NaCl + 3 H₂O + Na₂S₄O₆ + 2 Na⁺
2.0mL of the sample of bleach are:
2.0mL ₓ (1.084g / mL) ₓ (6 / 100) ₓ (1 mol / 74.44g) = 1.75x10⁻³ moles of NaClO
As 1 mole of NaClO reacts with 2 moles of thiosulfate:
1.75x10⁻³ moles of NaClO ₓ (2 mol Na₂S₂O₃ / 1 mol NaClO) =
3.50x10⁻³ moles of Na₂S₂O₃
If you have a 0.150M solution of thiosulfate, mL of this solution you need to reach the end point of the titration are:
3.50x10⁻³ moles of Na₂S₂O₃ ₓ (1L / 0.150mol) = 0.0233L =
23.3mL of 0.150M sodium thiosulfatethe amount of order in an isolated system cannot increase; it may only stay the same or decrease. This expresses which of the following?
Conservation of mass
The First Law of Thermodynamics
The second Law of Thermodynamics
Kinetic Theory
The definition of work
the definition of heat
Answer:
Second law of thermodynamics.
Explanation:
Second law of thermodynamics states the entropy or order in an isolated system always increases. The isolated system evolve spontaneously toward thermal thermal equilibrium.
For example if a room is untidy and dirty,it will become messy over time and disorder. So when the room is cleaned, there won't be disorderliness and entropy will decrease.
Erbium (Er) is element 68 on the periodic table. A sample contains 5.04×1023 atoms of Er. Calculate the amount of Er.
Answer:
139.98 g to nearest hundredth.
Explanation:
Using Avogadro's Number:
One mole (167.26 g) of Erbium equates to 6.022141 * 10^23 atoms.
So 5.04 * 10^23 = 167.26 * 5.04/6.022141
= 139,98 g.
Br2(g) + 3 F2(g) ⇄ 2 BrF3(g) Kp = 5.4 × 108 0.30 atm of Br2 and 0.60 atm of F2 are placed in a 3.0 L container and the system is allowed to reach equilibrium. Calculate the pressureof Br2 at equilibrium.
Answer:
The pressure at equilibrium of Br₂ is 0.10048 atm
Explanation:
Based on the reaction:
Br₂(g) + 3 F₂(g) ⇄ 2 BrF₃(g)
Kp is defined as:
[tex]Kp = \frac{P_{BrF_3}^2}{P_{Br_2}P_{F_2}^3}[/tex] = 5.4x10⁸
If initial pressures of Br₂ and F₂ are 0.30atm and 0.60atm respectively, the pressures in equilibrium are:
Br₂ = 0.30atm - X
F₂ = 0.60atm - 3X
BrF₃ = 2X
Replacing in Kp formula:
5.4x10⁸ = [2X]² / [0.30atm - X] [0.60atm - 3X]³
5.4x10⁸ = 4X² / [0.30 - X] [0.216 - 3.24 X + 16.2 X² - 27 X³]
5.4x10⁸ = 4X² / 0.0648 - 1.188 X + 8.1 X² - 24.3 X³ + 27 X⁴
Solving for X:
X = 0.3000 → False answer because produce negative concentrations.
X = 0.19952. Replacing in equation of Br₂:
Br₂ = 0.30atm - 0.19952atm = 0.10048 atm
When a 20.0 g sample of an unknown compound is dissolve in 500. G of benzene, the freezing point of the resulting solution is 3.77 o C. The freezing point 9f pure benzene is 5.48 o C and Kf for benzene is 5.12 o C/m. Calculate the molar mass of the unknown
Answer:
The correct answer is 116.3 g/mol
Explanation:
When a solute is added to a solvent, the freezing point decreases. That is called freezeing point depression and is given by the following expression:
ΔTf= Kf x m
Where ΔTf is the decrease in freezing point (final temperature - initial temperature), Kf is the freezeing point constant, m is the molality of the solution.
We have the following data:
Kf= 5.12ºC/m
ΔTf= 5.48ºC - 3.77ºC = 1.71ºC
We can calculate the molality of the solution from the mathematical expression for freezeing point as follows:
m = ΔTf/Kf = 1.71ºC/(5.12º C/m)= 0.334 m
The molality is the number of moles of solute in 1 kg of solvent. The solute was added to 500 g of solvent (benzene), so we can multiply the molality by the grams of solvent (500 g = 0.5 kg) to obtain the number of moles:
0.334 mol/kg x 0.5 kg = 0.172 moles
We know that the molar mass is equal to the mass of compound per mole, so we divide the mass into the moles to obtain the molar mass as follows:
MM = mass/moles= 20.0 g/0.172 moles = 116.3 g/mol
Sodium metal and water react to form hydrogen and sodium hydroxide. If 11.96 g of sodium react with water to form 0.52 g of hydrogen and 20.80 g of sodium hydroxide, what mass of water was involved in the reaction
Answer:
9.36g of H2O.
Explanation:
We'll begin by writing the balanced equation for the reaction.
2Na + 2H2O —> 2NaOH + H2
Next, we shall determine the mass of Na and H2O that reacted from the balanced equation.
This is illustrated below:
Molar mass of Na = 23g/mol
Mass of Na from the balanced equation = 2 x 23 = 46g
Molar mass of H2O = (2x1) + 16 = 18g/mol
Mass of H2O from the balanced equation = 2 x 18 = 36g
From the balanced equation above,
46g of Na reacted with 36g of H2O.
Now, we can determine the mass of H2O involved in reaction as follow:
From the balanced equation above,
46g of Na reacted with 36g of H2O.
Therefore, 11.96g of Na will react with = (11.96 x 36)/46 = 9.36g of H2O.
Therefore, 9.36g of H2O were used for the reaction.
The reaction described by H2(g)+I2(g)⟶2HI(g) has an experimentally determined rate law of rate=k[H2][I2] Some proposed mechanisms for this reaction are: Mechanism A (1) H2(g)+I2(g)−→k12HI(g)(one-step reaction) Mechanism B (1) I2(g)⥫⥬=k−1k12I(g)(fast, equilibrium) (2) H2(g)+2I(g)−→k22HI(g) (slow) Mechanism C (1) I2(g)⥫⥬=k−1k12I(g)(fast, equilibrium) (2) I(g)+H2(g)−→k2HI(g)+H(g) (slow) (3) H(g)+I(g)−→k3HI(g) (fast) Which of these mechanisms are consistent with the observed rate law? mechanism A mechanism C mechanism B In 1967, J. H. Sullivan showed that this reaction was dramatically catalyzed by light when the energy of the light was sufficient to break the I−I bond in an I2 molecule. Which mechanism or mechanisms are consistent with both the rate law and this additional observation? mechanism A mechanism C mechanism B
Answer:
Mechanism A and B are consistent with observed rate law
Mechanism A is consistent with the observation of J. H. Sullivan
Explanation:
In a mechanism of a reaction, the rate is determinated by the slow step of the mechanism.
In the proposed mechanisms:
Mechanism A
(1) H2(g)+I2(g)→2HI(g)(one-step reaction)
Mechanism B
(1) I2(g)⇄2I(g)(fast, equilibrium)
(2) H2(g)+2I(g)→2HI(g) (slow)
Mechanism C
(1) I2(g) ⇄ 2I(g)(fast, equilibrium)
(2) I(g)+H2(g) ⇄ HI(g)+H(g) (slow)
(3) H(g)+I(g)→HI(g) (fast)
The rate laws are:
A: rate = k₁ [H2] [I2]
B: rate = k₂ [H2] [I]²
As:
K-1 [I]² = K1 [I2]:
rate = k' [H2] [I2]
Where K' = K1 * K2
C: rate = k₁ [H2] [I]
As:
K-1 [I]² = K1 [I2]:
rate = k' [H2] [I2]^1/2
Thus, just mechanism A and B are consistent with observed rate law
In the equilibrium of B, you can see the I-I bond is broken in a fast equilibrium (That means the rupture of the bond is not a determinating step in the reaction), but in mechanism A, the fast rupture of I-I bond could increase in a big way the rate of the reaction. Thus, just mechanism A is consistent with the observation of J. H. Sullivan
A sample of sulfuryl fluoride, SO2F2, has a mass of 19.2 g. What amount, in moles, does this mass represent?
Answer:
0.188 moles
Explanation:
moles=mass/molar mass
moles= 19.2/ (32+32+38)
moles= 0.188
Answer:
0.188 moles.
Explanation:
Molar mass of SO2F2
= 32 + 2*16 + 2 * 19
= 102 g.
So 19.2g = 19.2 / 102
= 0.188 moles.
Aluminum has a density of 2.70 g/mL. Calculate the mass (in grams) of a piece of aluminum having a volume of 374 mL. Express your answer to three significant figures.
Answer:
Explanation:I don't say u must have to mark my ans as brainliest but if it has really helped u plz don't forget to thnk me...
1. Legătura covalentă este legătura chimică ce se stabileşte: a) prin punere în comun de electroni; b) prin transfer de electroni; c) prin punere în comun sau prin transfer de electroni. 2. Legătura covalentă se stabileşte între: a) două metale ; b) două nemetale; c) un metal şi un nemetal. 3. O legătură covalentă se stabileşte: a) între hidrogen şi sodiu ; b) între azot şi hidrogen; c) între aluminiu şi oxigen.. 4. Legăturile covalente sunt de două feluri: a) legături covalente simple si legaturi covalente duble; b) legături covalente polare şi legături covalente nepolare; c) nici un raspuns nu este corect. 5. Selectează substanțele în moleculele cărora atomii sunt uniți prin legătură ionică: a) oxid de fosfor P2O5; b)clorură de potasiu KCl; c) apă H2O
Answer:
1) Option A is correct.
The covalent bond is the chemical bond that is established by pooling of electrons.
2) Option B is correct.
The covalent bond is established between two non-metals.
3) Option B is correct.
A covalent bond is established between nitrogen and hydrogen.
4) Option B is correct.
Covalent bonds are of two types; polar covalent bonds and non-polar covalent bonds.
5) Option B is correct.
Select the substances in the molecules of which the atoms are united by ionic bond.
potassium chloride KCl
1) Opțiunea A este corectă.
Legătura covalentă este legătura chimică care se stabilește prin punerea în comun a electronilor.
2) Opțiunea B este corectă.
Legătura covalentă este stabilită între două nemetale.
3) Opțiunea B este corectă.
Se stabilește o legătură covalentă între azot și hidrogen.
4) Opțiunea B este corectă.
Legăturile covalente sunt de două tipuri; legături covalente polare și legături covalente nepolare.
5) Opțiunea B este corectă.
Selectați substanțele din moleculele cărora atomii sunt uniți prin legătură ionică. clorură de potasiu KCl
Explanation:
English Translation
1) The covalent bond is the chemical bond that is established: a) by pooling electrons; b) by electron transfer; c) by pooling or electron transfer.
2) The covalent bond is established between: a) two metals; b) two non-metals; c) a metal and a non-metal.
3) A covalent bond is established: a) between hydrogen and sodium; b) between nitrogen and hydrogen; c) between aluminum and oxygen.
4) Covalent bonds are of two types: a) single covalent bonds and double covalent bonds; b) polar covalent bonds and non-polar covalent bonds; c) no answer is correct.
5) Select the substances in the molecules of which the atoms are united by ionic bond: a) phosphorus oxide P2O5; b) potassium chloride KCl; c) H2O water
Solution
Covalent bonds are bonds that result from the sharing/pooling of electrons by two non-metallic atoms. When the electronegativity difference between the two atoms in a cobalent bond is substantial, a polar covalent bond results (in which the shared electrons are closer to the more electronegative atom of the pair). If the electronegativity difference isn't significant, a non-polar covalent bond ensues, in which the shared electrons are approximately equidistant from both atoms.
1) The covalent bond is the chemical bond that is established by pooling of electrons.
Already explained above.
2) The covalent bond is established between two non-metals.
Already explained too.
3) A covalent bond is established between nitrogen and hydrogen.
Of the three options, only option B contains two elements, nitrogen and hydrogen, which are both non-metals amd this satisfy the condition for the formation of a covalent bond.
4) Covalent bonds are of two types; polar covalent bonds and non-polar covalent bonds.
Already explained above.
5) Select the substances in the molecules of which the atoms are united by ionic bond.
potassium chloride KCl
Ionic bonds result from the transfer of electrons from metals (electropositive elements) to non-metals (electronegative elements). Of the 3 options provided, only potassium chloride is a coming together of a metal and a non metal.
In Romanian/In limba romana
Legăturile covalente sunt legături care rezultă din împărțirea / îmbinarea electronilor de către doi atomi nemetalici. Când diferența de electronegativitate între cei doi atomi dintr-o legătură cobalentă este substanțială, rezultă o legătură covalentă polară (în care electronii partajați sunt mai apropiați de atomul mai electronegativ al perechii). Dacă diferența de electronegativitate nu este semnificativă, apare o legătură covalentă non-polară, în care electronii partajați sunt aproximativ echidistanți de la ambii atomi.
Legăturile ionice rezultă din transferul electronilor de la metale (elemente electropozitive) la nemetalele (elemente electronegative).
Hope this Helps!!!
Sper că acest lucru vă ajută!!!!
Convert 3.4 x 10^23 molecules of NaCl to grams
Answer:
[tex]m_{NaCl}=33g[/tex]
Explanation:
Hello,
In this case, in order to compute the grams of sodium chloride starting by the molecules, the first step is to compute the moles contained in the given amount of molecules by using the Avogadro's number:
[tex]n_{NaCl}=3.4x10^{23}molecules*\frac{1mol}{6.022x10^{23}molecules} =0.56mol[/tex]
Then, by using the molar mass of sodium chloride (58.45 g/mol) we can directly compute the grams:
[tex]m_{NaCl}=0.56mol*\frac{58.45g}{1mol} \\\\m_{NaCl}=33g[/tex]
Regards.
1. An isotope of cesium-137 has a half-life of 30 years. If 5.0 g of cesium-
137 decays over 60 years, how many grams will remain?
Answer:
1.25 g
Explanation:
Now we have to use the formula;
N/No = (1/2)^t/t1/2
N= mass of cesium-137 left after a time t (the unknown)
No= mass of cesium-137 present at the beginning = 5.0 g
t= time taken for 5.0 g of cesium-137 to decay =60 years
t1/2= half life of cesium-137= 30 years
Substituting values;
N/5= (1/2)^60/30
N/5= (1/2)^2
N/5= 1/4
4N= 5
N= 5/4
N= 1.25 g
Therefore, 1.25 g of cesium-137 will remain after 60 years.
What volume of a 3.5 M LiOH solution is needed to titrate 253 ml of a 2.75 M HF solution?
Answer:
198.8mL
Explanation:
Step 1:
Data obtained from the question:
Molarity of base (Mb) = 3.5M
Volume of base (Vb) =..?
Molarity of acid (Va) = 2.75M
Volume of acid (Va) = 253mL
Step 2:
The balanced equation for the reaction.
HF + LiOH —> LiF + H2O
From the balanced equation above,
The mole ratio of the acid (nA) = 1
The mole ratio of the base (nB) = 1
Step 3:
Determination of the volume of the base, LiOH needed for the reaction.
The volume of the base needed for the reaction can be obtained as follow:
MaVa /MbVb = nA/nB
2.75 x 253 / 3.5 x Vb = 1
Cross multiply
3.5 x Vb = 2.75 x 253
Divide both side by 3.5
Vb = 2.75 x 253 / 3.5
Vb = 198.8mL
Therefore, the volume of the base needed for the reaction is 198.8mL
Aqueous solutions of ammonium oxalate and lithium acetate react.
Answer:
The reaction is a double displacement reaction
Explanation:
Let us consider the reaction equation of the reaction between ammonium oxalate and lithium acetate.
(NH4)2C2O4(aq) +2 CH3COOLi(aq) -------> 2NH4CH3CO2(aq) + Li2C2O4(s)
This is a displacement reaction. A double displacement reaction is a type of reaction in which two reactants exchange their ions to form two new compounds. Double displacement reactions usually lead to the formation of a solid product which is also called a precipitate.
The general form of a Double displacement reaction is of the format:
AB + CD → AD + CB
Where A,B,C and D represents different ions respectively.
A double displacement reaction can also be referred to as salt metathesis reaction, double replacement reaction, exchange reaction, or a double decomposition reaction, although the latter term is more strictly used when one or more of the reactants does not dissolve in the solvent.
Water is intentionally present in a state where its molecules are far apart during a change of state is molecule slow down which change of state has most likely taking place
Answer:
melting
Explanation:
Why we need blood cholesterol?
Answer:
We need blood cholesterol because our body uses it to build your structure of cell membranes, make hormones like oestrogen, and testosterone, and to help your metabolism work well.
Answer:
our cells need some cholesterol but too much cuz it can cause problems. HDL carries cholesterol to your liver, where it can be removed from the body.so it helps protect your heart from atherosclerosis
Explanation:
1. The chemical formula for sodium bromide is NaB.*
True
False
Answer:
NaBr
Explanation:
Bromine's symbol is Br, not B, for B is for Boron
Which evidence supports the idea that Cosmic Microwave Background radiation is a remnant of the Big Bang?
A. Its temperature is uniform.
B. Its temperature fluctuates greatly.
C. Its mass fluctuates greatly.
D. Its mass is uniform.
Answer:
A. Its temperature is uniform.
Explanation:
Cosmic Microwave Background radiation is a remnant of the Big Bang talks about the universe being very hot thereby causing its expansion with a corresponding cooling of the gases within it. The Cosmic Microwave Background radiation being what is left of the radiation after the Big Bang occurrence.
The temperature was uniform with very little fluctuations which makes the A the right choice.
Answer:
a
Explanation:
0.76 g of lead(2) nitrate was dissolvedin 50.00ml of water a d treated with 25.00 ml of 0.2010M sodium sulfate inoder to determine a content of lead 2 ion. A white precipitate was formed and it was collected and dried. Calculate the amount of precipitate formed in this reaction
Answer:
Mass of precipitate (PbSO₄) formed = 0.696 g
Explanation:
The reaction of Lead II Nitrate and Sodium Sulfate is given as
Pb(NO₃)₂ (aq) + Na₂SO₄ (aq) → 2NaNO₃ (aq) + PbSO₄ (s)
The precipitate from this reaction is the PbSO₄
0.76 g of Pb(NO₃)₂ is available for reaction, we convert to number of moles
Number of moles = (Mass)/(Molar Mass)
Mass = 0.76 g
Molar mass of Pb(NO₃)₂ = 331.2 g/mol
Number of moles of Pb(NO₃)₂ = (0.76/331.2) = 0.002294686 moles = 0.002295 moles
25.00 ml of 0.2010M sodium sulfate is available for the reaction, we also conert to number of moles.
Number of moles = (Concentration in mol/L) × (Volume in L)
Concentration of Na₂SO₄ in mol/L = 0.201 M
Volume of Na₂SO₄ in L = (25/1000) = 0.025 L
Number of moles of Na₂SO₄ = 0.201 × 0.025 = 0.005025 moles
From the stoichiometric balance of the reaction, 1 mole of Pb(NO₃)₂ reacts with 1 mole of Na₂SO₄
Hence, this indicates that Pb(NO₃)₂ is the limiting reagent as it is in short supply and it will therefore dictate the amount of precipitate (PbSO₄) formed.
1 mole of Pb(NO₃)₂ gives 1 mole of the precipitate (PbSO₄)
0.002295 mole of Pb(NO₃)₂ will give 0.002295 mole of the precipitate (PbSO₄)
Mass = (Number of moles) × (Molar mass)
Number of moles of precipitate (PbSO₄) formed = 0.002295 mole
Molar mass of PbSO₄ = 303.26 g/mol
Mass of precipitate (PbSO₄) formed = 0.002295 × 303.26 = 0.6958864734 = 0.696 g
Hope this Helps!!!
convert 4.56 cm to mm
Answer:
45.6 mm
Explanation:
1 centimeter = 10 millimeter
4.56 cm = x mm
x = 4.56 × 10
= 45.6 mm
The pressure gauge on a tank registers the gauge pressure, which is the difference between the interior pressure and exterior pressure. When the tank is full of oxygen (O2), it contains 15.0 kg of the gas at a gauge pressure of 36.0 atm. Determine the mass of oxygen that has been withdrawn from the tank when the pressure reading is 21.6 atm. Assume the temperature of the tank remains constant.
Answer:
GOOD DAY ON YOUR QUIZ
Explanation:
How much of a 0.250 M lithium hydroxide is required to neutralize 20.0 mL of 0.345M chlorous acid?
Answer:
27.6mL of LiOH 0.250M
Explanation:
The reaction of lithium hydroxide (LiOH) with chlorous acid (HClO₂) is:
LiOH + HClO₂ → LiClO₂ + H₂O
That means, 1 mole of hydroxide reacts per mole of acid
Moles of 20.0 mL = 0.0200L of 0.345M chlorous acid are:
0.0200L ₓ (0.345mol / L) = 6.90x10⁻³ moles of HClO₂
To neutralize this acid, you need to add the same number of moles of LiOH, that is 6.90x10⁻³ moles. As the LiOH contains 0.250 moles / L:
6.90x10⁻³ moles ₓ (1L / 0.250mol) = 0.0276L of LiOH =
27.6mL of LiOH 0.250MAshley notice that the mineral appear metallic under the light. What property was actually measuring?
Answer: The property is called Luster
Explanation:
Luster is a term used to describe the appearance of light from the surface of the mineral when it reflects light. The two types of classification of Luster is Mettalic or Non Mettalic.
some examples of minerals with mettalic lustre are --- Galena, graphite, Gold, Silver, Copper etc
Some examples of minerals with non mettalic lustre are--- Barite, Serpentine, Fluorite etc.
Answer:
Lustrous property
Explanation:
Materials like metals that have lustre usually glow or display sheen when light comes in contact with the surface of the material.
It is derived from the Latin word "lux" meaning "light", which is indicative of radiance or gloss.
Lustre is a common property of metals, including sonourousity, malleability and ductility amongst others.
Addition of an excess of lead (II) nitrate to a 50.0mL solution of magnesium chloride caused a formation of 7.35g of lead (II) chloride precipitate. What was the molar concentration of chloride ions in the solution (in mol/L)?
Answer:
[Cl⁻] = 0.016M
Explanation:
First of all, we determine the reaction:
Pb(NO₃)₂ (aq) + MgCl₂ (aq) → PbCl₂ (s) ↓ + Mg(NO₃)₂(aq)
This is a solubility equilibrium, where you have a precipitate formed, lead(II) chloride. This salt can be dissociated as:
PbCl₂(s) ⇄ Pb²⁺ (aq) + 2Cl⁻ (aq) Kps
Initial x
React s
Eq x - s s 2s
As this is an equilibrium, the Kps works as the constant (Solubility product):
Kps = s . (2s)²
Kps = 4s³ = 1.7ₓ10⁻⁵
4s³ = 1.7ₓ10⁻⁵
s = ∛(1.7ₓ10⁻⁵ . 1/4)
s = 0.016 M
