Answer:
b. a compound.
Explanation:
Electrolysis is described as a mechanism in which ionic compounds are decomposed into their elements by transmitting a direct electric current via the compound in a liquid state. At the cathode, the cations are reduced and anions at the anode are oxidized. There is an exchange between ions and atoms in the electrolysis process caused by the addition or removal between electrons from the external circuit. As per the question, the original substance is a compound because the electrolysis method is used to obtain pure elements from their respective compound.
Next, break down the equation shown into the skeletal half-reactions for oxidation and reduction. Which of
these pairs shows the two skeletal half-reactions with their correct assignments?
reduction half reaction: HNO, NO
oxidation half reaction SH,SO,
oxidation half reaction: HNO3 -> NO
reduction half reaction: SH2SO,
reduction half reaction: HNO3 -H,SO,
oxidation half reaction S -> H2SO4
Answer:
Its answer A
Explanation:
I just took the test
Answer:
A:
reduction half reaction: HNO3-> NO
oxidation half reaction S->H2SO4
Explanation:
I really need help with these chemistry questions pleasee
Answer:
The answer to your question is given below
Explanation:
8. The equation for the reaction is given below:
Mg3N2 + H2O –> Mg(OH)2 + NH3
Number of reactant atoms before balancing:
Mg = 3
N = 2
H = 2
O = 1
Number of product atoms before balancing:
Mg = 1
N = 1
H = 5
O = 2
Now, let us balanced the equation.
Mg3N2 + H2O –> Mg(OH)2 + NH3
There are 3 atoms of Mg on the left side and 1 atom on the right side. It can be balance by putting 3 in front of Mg(OH)2 as shown below:
Mg3N2 + H2O –> 3Mg(OH)2 + NH3
There are 2 atoms of N on the left side and 1 atom on the right side. It can be balance by putting 2 in front of NH3 as shown below:
Mg3N2 + H2O –> 3Mg(OH)2 + 2NH3
There 2 atoms of H on the left side and a total of 12 atoms on the right side. It can be balance by putting 6 in front of H2O as shown below:
Mg3N2 + 6H2O –> 3Mg(OH)2 + 2NH3
Now the equation is balanced.
Number of reactant atoms after balancing:
Mg = 3
N = 2
H = 12
O = 6
Number of product atoms after balancing:
Mg = 3
N = 2
H = 12
O = 6
9. When methane react with steam, carbon dioxide and hydrogen gas are produced as shown below:
CH4 + H2O –> CO + H2
Now, let us balance the equation. This is illustrated below:
There are a total of 6 atoms of H on the left side and 2 atoms on the right side. It can be balance by putting 3 in front of H2 as shown below:
CH4 + H2O –> CO + 3H2
Now the equation is balanced.
At what angle(s) should investigators photograph a tool mark? A. parallel B. perpendicular C. 45 degrees D. varying
Answer:
B
Explanation:
Which compound can be used to preserve biological specimens? A central C is double bonded to an O, and single bonded to 2 H. A chain, reading from left: C H 3 bonded to C, bonded to O, bonded to C H 2, bonded to C H2, bonded to C H 3. The single C near the beginning of the chain is double bonded to O. C H 3 single bonded to C, which is double bonded above right to O, and below right to C H 2, which is bonded to C H 3. A central C is double bonded to an O above, and single bonded to C H 3 below left and O H below right.
Answer:
A central C is double bonded to an O, and single bonded to 2 H
Explanation:
Methanal, also known as formaldehyde, is a chemical compound used to preserve dead biological specimens for further study. It is called formalin when in a solution and it helps keep specimens in a fresh state by hardening the tissues of the specimen involved.
Formaldehyde is a gaseous compound that has an aldehyde functional group i.e. -CHO and has a chemical formula, H-CHO or CH2O as described in the question that a central C is double bonded to an O, and single bonded to 2 H (see attached image for structural formula).
The chemical for the preservation of biological specimens has consisted of central C with a double-bonded O and two single-bonded hydrogens. Thus, option A is correct.
The biological compound that has been used to preserve biological specimens has been methanal. It has been the simplest aldehyde. The chemical formula of formaldehyde, also known as methanal has been H-CHO.
The structure of formaldehyde has been consisted with single bond between H and C. The central carbon has been associated with a double bond between the C and O, with single-bonded H.
Thus, the chemical for preservation of biological specimen has been consisted of central C with a double-bonded O and two single-bonded hydrogens. Thus, option A is correct.
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From where in the solar system did scientists conduct their spectral anaylses in 1948? How do you know?
Answer:
They conducted it from earth
Explanation:
There had never been anything capable of observing it from space launched at that time because Sputnik wasn't even launched
5.What is the chemibal formula for lead (II) iodide
Answer: The chemical formula for lead (II) iodide is [tex]PbI_2[/tex]
Explanation:
Lead (II) iodide is a ionic compound because it are formed by transference of electrons between metals and non metals.The bond formed between a metal and a non-metal is always ionic in nature.
For formation of a neutral ionic compound, the charges on cation and anion must be balanced. The cation is formed by loss of electrons by metals and anions are formed by gain of electrons by non metals.
The nomenclature of ionic compounds is given by:
1. Positive is written first followed by the oxidation state of metal in roman numerals in square brackets.
2. The negative ion is written next and a suffix is added at the end of the negative ion. The suffix written is '-ide'.
The chemical formula for lead (II) iodide is [tex]PbI_2[/tex]
describe two ways in which sodium chloride is different from sodium
Answer:
sodium chloride is a component is a salt made of a metal Sodium and a non chlorine is a alone only and element and very less stable until bonded with them metal like a n, a, k or H
The weight of the buggy was 40N on Mars. When the buggy landed on Mars it rested on an area of 0.025 m2. Calculate the pressure exerted by the buggy on the surface of Mars
Answer:
The pressure exerted by the buggy on the surface of Mars is 1600 pascals.
Explanation:
The pressure is determined by the definition of stress, which is the force exerted by the buggy on the martian surface divided by the contact area of the latter:
[tex]\sigma = \frac{F}{A}[/tex]
Where:
[tex]\sigma[/tex] - Stress, measured in pascals.
[tex]F[/tex] - Force, measured in newtons.
[tex]A[/tex] - Area, measured in square meters.
The force is the weight of the buggy (40 N) and [tex]A = 0.025\,m^{2}[/tex], the stress is now calculated:
[tex]\sigma = \frac{40\,N}{0.025\,m^{2}}[/tex]
[tex]\sigma = 1600\,Pa[/tex]
The pressure exerted by the buggy on the surface of Mars is 1600 pascals.
Primary succession is most likely caused by?
Answer:
volcanic eruption.
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A mixture is best described as:
A. None of these
B. A pure chemical substance consisting of one type of atom.
OC. The basic building blocks of matter.
D. Two or more elements or compounds that are mixed together but not chemically bonded.
Answer:
D. Two or more elements or compounds that are mixed together but not chemically bonded.
Explanation:
Mixture is unique as it is not chemically bonded and individual entities such as elements or compounds keep their unique identities.
Answer:
Mixture consists of two or three elements or compounds that are mixed together but not chemically bonded.
A balloon has a volume of 0.56 L and a pressure of 1.34 atm. The balloons pressure decreased to 0.85 atm,
what is the balloons new volume? Write your solution, including the formula used.
Answer:
[tex]\large \boxed{\text{0.88 L}}[/tex]
Explanation:
The temperature and amount of gas are constant, so we can use Boyle’s Law.
[tex]p_{1}V_{1} = p_{2}V_{2}[/tex]
Data:
[tex]\begin{array}{rcrrcl}p_{1}& =& \text{1.34 atm}\qquad & V_{1} &= & \text{ 0.56 L} \\p_{2}& =& \text{0.85 atm}\qquad & V_{2} &= & ?\\\end{array}[/tex]
Calculations:
[tex]\begin{array}{rcl}\text{1.34 atm} \times \text{0.56 L} & =& \text{0.85 atm} \times V_{2}\\\text{0.750 L} & = & 0.85V_{2}\\V_{2} & = &\dfrac{0.750}{0.85}\\\\& = &\textbf{0.88 L}\\\end{array}\\\text{The balloon's new volume is $ \large \boxed{\textbf{0.88 L}}$}[/tex]
You have 3.00 m3 of a fixed mass of a gas at 150 kPa. Calculate the pressure if the volume is reduced to 1.20 m3 at a constant temperature.
Answer:
Solution:
Explanation:
V1 = 3.00m3
T1 = 150kPa
V2 = 1.20m3
T2 = x
As ,
V1 = V2
T1 T2
3.00 = 1.20
150 X
3.00 x X = 150 x 1.20
3.00X = 180
X = 180
3.00
X = 60 kPa
The final pressure can be calculated using Boyle's law. The final pressure of the gas if the volume is increased from 3 m³ to 1.20 m³ with an initial pressure of 150 kPa is obtained as 375 kPa.
What is Boyle's law?Boyle's law states that at constant temperature, the volume of a gas is inversely proportional to the pressure of the gas. Hence, volume decreases with increase in pressure and vice versa.
If P₁ and V₁ be the initial pressure and volume respectively and P₂, V₂ be their final quantities, then the relation between them can be written as:
P₁ V₁ = P₂ V₂ .
It is given that the initial volume and pressure is 3 m³ and 150 kPa and the final volume is 1.20 m³ . Then, the final pressure is calculated as follows:
P₂ = P₁ V₁ / V₂
= (3 m³ × 150 kPa) / 1.20 m³
= 375 kPa
Hence, the final pressure of the gas will be 375 kPa.
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Describe how you could determine the specific heat of a sample of a solid substance. You may assume
at the substance does not react with water. In your answer, make sure to include a description of what
quipment you would use and how you would interpret the data you collected.
To calculate the actual heat, I'd use calorimetric to weigh a sample mass. I 'd calculate the mass of a material sample. At a specified temperature, I will heat the material. I should position the heated material inside a calorimeter for coffee cup containing an initially established mass of water. I 'd wait for the weather to stabilize and then measure the difference in weather. To assess the sum of energy consumed, I will use the increase in water temperatures. For measure real heat I will use the sum of energy per material, weight, and temperature shift.
-------------------------------
Hope this helps!
Brainliest would be great!
-------------------------------
With all care,
07x12!
Answer:
-I would use calorimetry to determine the specific heat.
-I would measure the mass of a sample of the substance.
-I would heat the substance to a known temperature.
-I would place the heated substance into a coffee-cup calorimeter containing a known mass of water with a known initial temperature.
-I would wait for the temperature to equilibrate, then calculate temperature change.
-I would use the temperature change of water to determine the amount of energy absorbed.
-I would use the amount of energy lost by substance, mass, and temperature change to calculate specific heat.
Which of the following is an amorphous solid?
O
A. Diamond
B. Graphite
O C. Glass
O D. Iron
Answer:
C. Glass
Explanation:
Amorphous solids have a non-crystalline structure and no order. In that case, Diamonds, Graphite, and Iron all have a crystalline structure and order. You are left with C as your answer.
Planets near the Sun are composed of mainly rock and iron. How does the Solar Nebula theory account for this?
Answer:
The Solar Nebula Theory accounts for the creation of solar systems, stars, and planets. The theory accounts for planet composition by stating that iron compounds, silicates, and dust clump together to form planetesimals. Because of the proximity of the sun, ices and gases cannot condensate near them, so they do not become gas giants. The planetesimals then collide together due to gravity and collect to form our rocky planets.
Explanation:
To increase the current in a circuit, which can be increased? A. voltage B. resistance C. interference D. ohms
Answer:
voltage I'm just guessing
Answer:
Option A
Explanation:
Looking at the following formula:
I = V/R
Where V is voltage, I is current and R is resistance
In the above equation, Current and Voltage are in direct relationship such that if I is increased , V is also increased and vice versa. So, To increase the current, voltage should be increased.
Which sequence represents the relationship between pressure and volume of an ideal gas as explained by the kinetic-molecular theory? more gas particles Right arrow. More collisions Right arrow. Higher pressure smaller volume Right arrow. Crowded particles Right arrow. Less collisions Right arrow. Lower pressure smaller volume Right arrow. Crowded particles Right arrow. More collisions Right arrow. Higher pressure more gas particles Right arrow. More kinetic energy Right arrow. More volume Right arrow. Higher pressure
Answer:
smaller volume ⇒ Crowded particles ⇒ More collisions ⇒ Higher pressure
Explanation:
Smaller the volume , more crowed the particles . Then the particles will have rapid collisions so the free mean path is decreased , hence the pressure will be increased as follows
[tex]P=\frac{K_bT}{\sqrt{2}\pi d^2\lambda }[/tex]
where λ is mean free path , P is pressure .
The sequence the represent the relationship between pressure and volume of an ideal gas is: smaller volume right arrow Crowded particles right arrow More collisions right arrow Higher pressure
The kinetic molecular theory made five postulates which are used to explain the behaviour of gases.
From the postulates, he uses the kinetic molecular theory to explain Boyle's Law because the majority of a gas's volume in space is usually empty and may be compressed.
So, when a gas is compressed without affecting its temperature, the average kinetic energy of the gas particles remains constant. The particles continue to flow at the same rate, but the container has reduced.
As a result, the particles go from one end of the container to another in less time. This suggests they're hitting the barriers (collision) more frequently. Each and every increase in the frequency of collisions with the walls, thus, results in an increase in the gas's pressure.
Hence, as the volume of a gas decreases, the pressure of the gas increases.
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What is the Ka of a 1.9 ~ 10-2 M
solution of carbonic acid (H2CO3)
with a pH of 3.88?
Ka = [ ? ] × 10!?)
Helllllp
Answer:
Ka = 9.2x10⁻⁷
Explanation:
The equilibrium of carbonic acid in water is:
H₂CO₃ ⇄ HCO₃⁻ + H⁺
Where Ka is defined as:
Ka = [HCO₃⁻] [H⁺] / [H₂CO₃]
The equilibrium concentration of the species is:
[H₂CO₃] = 1.9x10⁻² - X
[HCO₃⁻] = X
[H⁺] = X
As pH is -log[H⁺]
3.88 = -log[H⁺]
1.318x10⁻⁴ = [H⁺] = X
Replacing:
[H₂CO₃] = 1.9x10⁻² - 1.318x10⁻⁴ = 1.8868x10⁻²
[HCO₃⁻] = 1.318x10⁻⁴
[H⁺] = 1.318x10⁻⁴
Replacing in ka equation:
Ka = [1.318x10⁻⁴] [1.318x10⁻⁴] / [1.8868x10⁻²]
Ka = 9.2x10⁻⁷Answer: 9.2 x 10^-7
Explanation:
7.What is the chemical formula for Beryllium Nitride? *
Answer:
BE3N2
Explanation:
(Help please!!! important question!!!) A neutral atom has an atomic number of 20 and a mass number of 41; how many protons, neutrons, and electrons are found within the atom? (2 points) 21 protons 21 electrons and 20 neutrons, 20 protons 20 electrons and 21 neutrons, 1 protons 20 electron and 20 neutrons, 41 protons 41 electrons and 20 neutrons
Answer: 20 protons,20 electrons and 21 neutrons
Explanation: because the number of protons is the same as the atomic number, and if the atom is neutral it has the same number of protons and electrons. if the mass number is 41 it means that there are 21 neutrons because to find the mass number you have to add protons and neutrons, so 20 + 21 = 41 and to confirm it the neutrons have been subtracted from the mass number and the atomic number, so 41-20 = 21
15 Ethanoic acid reacts slowly with calcium carbonate.
Which statements explain why an increase in temperature increases the rate oft
1
The activation energy of the reaction is decreased.
2
There is an increase in collision rate.
3
The particles have more energy.
4
There will be fewer successful collisions.
А
1 and 2
B
1 and 3
с
2 and 3
D
2 and 4
Answer:
C
2and3
Explanation:
increase in temperature causes the particles to gain more energy
Which example is indirect evidence used to study Earth's interior?
O composition of minerals in a rock
age of a rock from within Earth
O location of an earthquake's epicenter
O texture of different core rock samples
Answer:
location of earthquakes epicenter
Explanation:
The location of an earthquake's epicenter is indirect evidence used to study Earth's interior. Therefore, option C is correct.
What is Earth's interior ?The Earth's interior is made up of four layers, three solid and one liquid—molten metal that is nearly as hot as the sun's surface. The deepest layer is a solid iron ball with a diameter of about 1,500 miles.
The Earth's core is significant for three reasons: (1) it generates the planet's magnetic field; (2) it contains information about the planet's early history of accretion; and (3) it contains information about the planet's earliest history of accretion.
Geologists use an indirect method as well. They use seismic waves instead of knocking on walls. Seismic waves are produced when earthquakes occur. Geologists study seismic waves and how they travel through the Earth.
Thus, option C is correct.
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The mass of .10 moles of iron is:
Answer:
so mass in gram=560grams
Explanation:
number of moles=10moles
molar mass=56grams/moles
mass in gram of Fe=?
as we know that
[tex]number of moles=\frac{mass in gram}{molar mass}[/tex]
evaluating the formula
number of moles×molar mass=mass in gram
mass in gram=10moles×56grams/moles
mass in gram=560grams
i hope this will help you :)
A scanning tunneling microscope allows imaging of _______ particles.
Answer:
Atomic particles
Explanation:
A scanning tunneling microscope is an instrument used to view any surfaces at the levels of an atom. It was invented in the nineteenth century.
Practice: Solve each of the following problems using dimensional analysis (or another method). Show your work. (Use a periodic table to look up the necessary atomic masses.) A. 75 g KMnO4 = molecules KMnO4 B. 7.23 × 1024 Al atoms = grams Al C. 9.23 × 1023 Au atoms = moles Au D. 125 g H3PO4 = molecules H3PO4 E. 0.75 moles CO2 = total atoms
Answer:
Explanation:
A )
molecular weight of KMnO₄ = 158
75 g KMnO4 = 75 / 158 moles
= ( 75 / 158 )x 6.02 x 10²³ molecules
= 2.857 x 10²³ molecules KMnO4
so 75g KMnO₄ = 2.857 x 10²³ molecules KMnO4
B )
7.23 × 10²⁴ Al atoms = grams Al
72.3 X 10²³ Al atoms = 72.3 X 10²³ / 6.02 X 10²³ moles of Al
= 12 moles of Al
= 12 x 27 gm of Al
= 324 gm of Al .
7.23 × 10²⁴ Al atoms = 324 grams Al
C )
9.23 × 10²³ Au atoms = moles Au
9.23 × 10²³Au atoms = 9.23 × 10²³ / 6.02 x 10²³ moles of Au
= 1.53 moles of Au .
D )
125 g H₃PO₄ = molecules H₃PO₄
125 g H₃PO₄ = 125 / 98 moles of H₃PO₄
= (125 / 98) x 6.02 x 10²³ molecules
= 7.678 x 10²³ molecules of H₃PO₄
125 g H₃PO₄ = 7.678 x 10²³ molecules H₃PO₄
E )
.75 moles of CO₂
= .75 x 6.02 x 10²³ molecules of CO₂
= 4.515 x 10²³ molecules of CO₂.
one molecule of CO₂ = 3 atoms
4.515 x 10²³ molecules of CO₂ = 3 x 4.515 x 10²³ atoms
= 13.545 x 10²³ atoms .
The molecules, atoms, and weight of all elements and compounds has been calculated.
(A) To calculate the molecules of a compound:
Molecules = [tex]\rm moles\;\times\;avagadro\;number[/tex]
Moles = [tex]\rm \frac{weight}{molecular\; weight}[/tex]
Moles of [tex]\rm KMnO_4[/tex] = [tex]\rm \frac{75}{158}[/tex]
Moles of [tex]\rm KMnO_4[/tex] = 0.474
Molecules of [tex]\rm KMnO_4[/tex] = [tex]\rm 0.474\;\times\;6.023\;\times\;10^2^3[/tex]
Molecules of [tex]\rm KMnO_4[/tex] = 2.85 [tex]\rm \times\;10^2^3[/tex]
(B) Weight of Al:
moles = [tex]\rm \frac{atoms}{avagadro\;number}[/tex]
Moles of Al = [tex]\rm \frac{7.23\;\times\;10^2^4}{6.023\;\times\;10^2^3}[/tex]
Moles of Al = 12
Weight of Al = [tex]\rm moles\;\times\;molecular\;weight[/tex]
Weight of Al = 12 [tex]\times[/tex] 27
Weight of Al = 324 grams
(C) Moles = [tex]\rm \frac{atoms}{avagadro\;number}[/tex]
Moles of Au = [tex]\rm \frac{9.23\;\times\;10^2^3}{6.023\;\times\;10^2^3}[/tex]
Moles of Au = 1.53 mol/liters
(D) Molecules = [tex]\rm moles\;\times\;avagadro\;number[/tex]
Moles = [tex]\rm \frac{weight}{molecular\; weight}[/tex]
Moles of [tex]\rm H_3PO_4[/tex] = [tex]\rm \frac{125}{98}[/tex]
Moles of [tex]\rm H_3PO_4[/tex] = 1.275
Molecules of [tex]\rm H_3PO_4[/tex] = 1.275 [tex]\rm \times\;6.023\;\times\;10^2^3[/tex]
Molecules of [tex]\rm H_3PO_4[/tex] = [tex]\rm 7.678\;\times\;10^2^3[/tex]
(E) Atoms of [tex]\rm CO_2[/tex]:
Molecules = [tex]\rm moles\;\times\;avagadro\;number[/tex]
Molecules of [tex]\rm CO_2[/tex] = 0.75 [tex]\rm \times\;6.023\;\times\;10^2^3[/tex]
Molecules of [tex]\rm CO_2[/tex] = 4.515 [tex]\rm \times\;10^2^3[/tex]
1 molecule of [tex]\rm CO_2[/tex] = 3 atoms
4.515 [tex]\rm \times\;10^2^3[/tex] molecules = [tex]\rm 4.515\;\times\;10^2^3\;\times\;3[/tex]
Atoms of [tex]\rm CO_2[/tex] = 13.545 [tex]\rm \times\;6.023\;\times\;10^2^3[/tex]
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2. The change in internal energy for the expansion of a gas sample is -4750 J. How much work is done if the gas sample loses 1125 J of heat to the surroundings? Is this work done by the gas or done by the surroundings?
Answer:
The work done by the gas expansion is 5875 J,
Since the work done is positive, the work is done by the gas on the surroundings.
Explanation:
Given;
change in internal energy, ΔU = -4750 J
heat transferred to the system, Q = 1125 J
The change in internal energy is given by;
ΔU = Q - W
Where;
W is the work done by the system
The work done by the system is calculated as;
W = Q - ΔU
W = 1125 - (-4750)
W = 1125 + 4750
W = 5875 J
Since the work done is positive, the work is done by the gas on the surroundings (energy flows from the gas to the surroundings).
Therefore, the work done by the gas expansion is 5875 J
How does the government control scientific research
Answer:
The government allocates a budget for research every year. The spending of that money is determined by government priorities. Some of the money is spent directly, in government-funded research centers.
Other money is distributed to other research institutions.
Money spent by other institutions for research has no government oversight.
Explanation:
If 56 J of heat is added to an aluminum can with a mass of 23.6 g , what is its temperature change? Specific heat capacity of aluminum is 0.903 J/g∘C.
Answer:
Q = mass x sph x temp change
temp change = Q/(mass x sph)
Temp change =57/(22 x .903)
Temp Change = 2.97 ∘C
Temp change 3.0 ∘C
or
We can use the heat equation,
Q = mcΔT
Where Q is the amount of energy transferred (J), m is the mass of the substance (g), c is the specific heat (J g⁻¹ °C⁻¹) and ΔT is the temperature difference (°C).
The given data
Q = 52 J
m = 28.4 g
c = 0.903 J g⁻¹ °C⁻¹
ΔT = ?
By applying the formula,
52 J = 28.4 g x 0.903 J g⁻¹ °C⁻¹ x ΔT
ΔT = 2.03 °C
Hence, the temperature change of aluminium during the heating process is 2.03 °C.
You arrive at a crime scene and are told the body of the victim is in the 10 m deep pool. You walk over to what you are told is a 12 m in diameter, cylindrical pool. From the outside of the pool, you can see that the body looks badly burnt. Your partner says, “It looks like our victim had been burned alive and tried to put out the fire by jumping in the pool. The victim likely drowned to death.”
Something does not sit right with you though. If there was a fire, where did it start? There are no signs of combustion anywhere. You aren’t so sure and ask the crime scene investigator to run a sample of the pool water before letting anybody try to pull the body out.
The CSI comes back to you and tells you that normal pool water pH is roughly around 7.2, but the pool pH is actually highly basic at a level of 13 with a concentration of hydroxide ions at 1.0 x 10-1 mol/L. It becomes obvious to you that the body wasn’t burned before going in to the pool , but AFTER and there was no fire needed!
You order the body to be removed from the pool, but the CSI interjects, “It would be too dangerous with a pH that high. I suggest you get some vinegar from the store and pour it in to the pool before hand to drop the pH to 7. Draining the pool would take far too long and we need to examine the body as soon as possible.” She asks one of your constables to go to the store to purchase 5 – 4L jugs of vinegar (pH = 2) to pour in the pool, as she states it is enough to bring the pH to a safe level of 7.
It sounds like it could be enough vinegar based on your knowledge of acids and bases, but you want to double-check her estimate before sending your constable to the store. Verify whether or not she is correct using calculations. A diagram may help you with your calculations.
Hint 1: 1m3 = 1000L
Hint 2: Vcylinder = πr2h
Answer:
The vinegar is not enough to neutralize the pool.
Explanation:
The [OH⁻] in the pool is 1.0x10⁻¹mol / L. To know how many moles of OH⁻ are in the solution, you must calculate volume of the pool thus:
V(pool) = πr²h
Where r, radius is d/2 = 12m/2 = 6m and h is deep of the pool = 10m
V(pool) = π(6m)²*10
V(pool) = 1131m³
As 1m³ = 1000L:
1131m³ × (1000L / 1m³) = 1131000L in the pool.
And moles of OH⁻ are:
1.0x10⁻¹mol / L ₓ 1131000L = 131100 moles of OH⁻ are in the pool
The neutralization of OH⁻ with H⁺ is:
OH⁻ + H⁺ → H₂O
That means to neutralize the pool you must add 131100 moles of H⁺.
The H⁺ concentration in a vinegar pH = 2 is:
pH = -log [H⁺]
2 = -log [H⁺]
1x10⁻²M = [H⁺]
4L are just 4x10⁻² moles of [H⁺]. As you need 131100 moles of H⁺:
The vinegar is not enough to neutralize the pool.help help please help me I need the answer ASAP
Solution A has a mass of 70g. Solution B has a mass of 35 g. when they are mixed, a chemical reaction occurs in which a gas is produced. if the mass of the final mixture is 90g, what mass of gas was produced???
Answer:
15 g
Explanation:
1. According to the Law of Conservation of Mass, the sum of the products should be 105 g because 70 g + 35 g = 105 g.
2. If 90g of solution was produced and there's supposed to be 105 g, then the remaining grams would be equal to the mass of the gas.
3. 105 g - 90g = 15 g