The acid - base properties of the salt :'
1) Strong acids and strong base
2) Strong acid , weak base, acid and weak acid
3) Weak acid, strong base , base and the weak acid
4) Weak acid and the weak base
1) A salt consisting of the conjugate base of a strong acid and conjugate acid of a strong base will be neutral since neither will react with water.
2) The salt consisting of the conjugate base of a strong acid and the conjugate acid of a weak base will be acidic since the conjugate acid of a weak acid is acidic.
3) A salt consisting of the conjugate base of a weak acid and the conjugate acid of a strong base will be basic since the conjugate base of a weak acid is basic.
4) A salt consisting of the conjugate base of a weak acid and conjugate acid of a weak base can be either acidic or basic depending on the relative Ka and Kb of the respective ions.
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The group of students then did an experiment using four different solutes to see which one would be best in their hot pack. To determine which solute would be best, the students mixed 20 g of each solute into separate containers that each held 50 mL of 24°C water. The students then recorded the temperature changes in each container. The data table below shows the maximum and minimum temperature they obtained for each solute, as well as the temperature difference.
Based on the value of temperature increase, the best solute to be used in the hot pack is calcium chloride.
What are exothermic reactions?Exothermic reactions are reactions in which heat is liberated or given by the substances reacting.
The reaction in hot packs are exothermic reactions.
Based on the increase in temperature observed when 20 g of each solute is mixed into separate containers that each held 50 mL of 24°C water, the best solute to be used in the hot pack is calcium chloride.
In conclusion, exothermic reactions give off heat.
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In the following equation, ______ is being oxidized and ______ is being reduced.
CO3 2- + 2H+ → CO2 + H2O
A. None of these
B. carbon, oxygen
C. carbon, hydrogen
D. hydrogen, carbon
[tex]oxidation \: number \: of \: oxygen = \\ before \: rxn = - 2 \\ after \: rxn = - 2[/tex]
[tex]oxidation \: number \: of \: hydrogen = \\ before \: rxn = + 1 \\ after \: rxn = \\ 2x - 2 = 0 \\ x = + 1[/tex]
[tex]oxidation \: number \: of \: carbon = \\ before \: rxn = \\ x - 6 = - 2 \\ x = 4 \\ after \: rxn = \\ x - 4 = 0 \\ x = 4[/tex]
Option A[tex]oxidation \: numbers \: remain \: constant \\ so \: none \:a re \: undergoing \: oxidation \: \\ nor \: reduction \: [/tex]
Answer:
D
Explanation:
I believe that is the answer
What is the wavelength of a photon if the energy is 7.69 × 10⁻¹⁹ j? (h = 6.626 × 10⁻³⁴ j • s)
The wavelength of a photon if the energy is 7.69 × 10⁻¹⁹ J is
Calculation,
Given energy = 7.69 × 10⁻¹⁹ J
Plank's constant = 6.626 × 10⁻³⁴ J.s
Formula used:
E = hv
E is the energyh is plank's constantv s frequencyv = c/ lemda
Where, c = speed of light =
lamda = wavelength of the photon
Putting the value of v in equation (i), and rearrange the equation.
E = hc/lemda = 6.626 × 10⁻³⁴ J×3[tex]10^{8}[/tex]/lemda = 7.69 × 10⁻¹⁹ J.s
lamda = 6.626 × 10⁻³⁴J×3[tex]10^{8}[/tex] m[tex]s^{-1}[/tex]/7.69 × 10⁻¹⁹J.s = 2.58× [tex]10^{-9}[/tex]m =2.58 nm
So, wavelength of a photon is 2.58 nm
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5. The maximum acceptable concentrations of the chemicals listed in Table 2 on page 283, are based on an average daily intake of 1.5 L of drinking water.
a) If a community’s drinking water contained the maximum acceptable levels of lead, how much lead would a person in the community consume in a year?
b) Would you willingly drink this water? Give reasons for your decision.
Based on the the US Environmental Protection Agency guidelines, the maximum allowable concentration of lead in drinking water, yearly intake of lead by the individual = 8.21 mg.
I would not willingly drink the water due to the risk of lead poisoning.
What is the maximum acceptable concentration of Lead in Drinking water?Based on the US Environmental Protection Agency guidelines, the maximum allowable concentration of lead in drinking water is 0.015 mg/L.
a)Given daily average intake of water is 1.5, in one year;
Volume of water intake = 1.5 * 365 = 547.5 L
Yearly intake of lead by the individual = 0.015 mg/L * 547.5
Yearly intake of lead by the individual = 8.21 mg
b) I would not willingly drink the water due to the risk of lead poisoning.
In conclusion, safe, drinking water should be free on contaminants such as lead to avoid lead poisoning.
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Place the following substances in order of increasing vapor pressure at a given temperature. SF6 SiH4 SF4
Substances in order of increasing vapor pressure at a given temperature is SF4 < SF6 < SiH4
The substance with the lowest vapor pressure will also have the greatest boiling point. A liquid attribute associated with evaporation is vapor pressure. The distribution of kinetic energy among the molecules in a liquid (or any substance) is influenced by the system's temperature.How do you determine vapor pressure?Vapor pressure in chemistry is the force that an evaporating substance exerts against the walls of a sealed container (converts to a gas). Use the Clausius-Clapeyron equation to determine the vapor pressure at a specific temperature: ln(P1/P2) = (Hvap/R)((1/T2) - (1/T1)Which has highest vapor pressure?
At the normal boiling point of a liquid, the vapor pressure is equal to the standard atmospheric pressure defined as 1 atmosphere, 760 Torr, 101.325 kPa, or 14.69595 psi. For example, at any given temperature, methyl chloride has the highest vapor pressure of any of the liquids in the chart.Learn more about vapor pressure
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In a voltaic cell, a salt bridge is needed to allow the motion of ____________ between the terminals. In the salt bridge, _____________ move toward the anode and _________ move toward the cathode.
In a voltaic cell, a salt bridge is needed to allow the motion of ions between the terminals. In the salt bridge, anions move toward the anode and cations move toward the cathode.
What is a voltaic cell?A voltaic cell is an electrochemical device that harnesses the power of a chemical process to generate electrical energy. A voltaic cell's key components are:
Anode, an electrode where oxidation takes place. Anions move toward the anode.Cathode, an electrode where reduction takes place. Cations move toward the cathode.A salt bridge is an electrolyte chamber required to finish the circuit in a voltaic cell.Half-cells are containers that serve as a barrier between the oxidation and reduction reactions.The external circuit, which typically has a load attached to it, is used to carry electron flow between the voltaic cell's electrodes.A load is a component of a circuit that uses an electron flow to carry out a certain task.Working of a voltaic cell:When an electrode is dipped into the electrolyte at the electrode and electrolyte contact surface in a voltaic cell, the electrode's atoms tend to produce positive ions in the electrolytic solution while leaving the electrode's electrons unaffected. The electrode thus acquires a negative charge.
Additionally, the electrolytic solution's positive ions have a propensity to deposit on the electrode, giving it a positive charge. The electrodes get positively or negatively charged in relation to the electrolyte as a result of the two opposite processes. As a result, there is a potential difference between the electrode and electrolyte. The term "electrode potential" refers to this potential difference.
Now, the electrode where reduction occurs is known as the cathode and turns positive in relation to the electrolytic solution, whereas the electrode where oxidation occurs is known as the anode and has a negative potential in relation to the electrolytic solution. This caused a potential difference to form between the voltaic cell's two electrodes. Cell Potential is the name given to this potential differential.
The voltaic cell's potential is sometimes referred to as its electromotive force (EMF) when no current is being drawn from it. Electrons begin to flow from the anode (negative electrode) to the cathode when an external circuit is connected to the voltaic cell (positive electrode). As a result, in the external circuit, the normal current flows from the positive terminal to the negative terminal.
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A mixture of methane (CH₄) and butane (C₄H₁₀) at one atmosphere pressure and 25°C has a density of 1.375 g/L. Assuming ideal behavior, what is the mass in grams of carbon that are in 1 liter of the mixture?
The mass of carbon in 1 liter of mixture = 1.108 g
What is the mass of carbon in 1 liter of the mixture?The mass of carbon in 1 liter of the mixture is determined as follows:
First the moles of gas is determined using the ideal gas formula:
n = PV/RTn = (1 * 1)/(0.08205L * 298)
n = 0.0409 mole of total gas
mass of gas is then determined using the formula:
mass = density * volumemass = 1 * 1.375
mass = 1.375 g
Let x = mass of CH₄ and y = mass of C₄H₁₀
x + y = 1.375 g
nCH₄ + nC₄H₁₀ = ntotat
moles = mass/molar mass
x + y = 1.695 => y = 1.695 - x
(x/molar mass of CH₄) + [(1.375 - x)/ molar mass C₄H₁₀ = 0.0409
x/16 + (1.375 - x)/58 = 0.0409
x = 0.380 g CH₄
y = 1.375 - 0.380
y = 0.995 g of C₄H₁₀
mass of C in CH₄ = 12/16 * 0.380 = 0.285
mass of C in C₄H₁₀ = 48/58 * 0.995 = 0.823
Mass of carbon in 1 liter of mixture = 0.285 + 0.823
Mass of carbon in 1 liter of mixture = 1.108 g
In conclusion, the carbon is the major component in the mixture.
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Blank + BaCl2 = BaSO4 + 2NaCl
How to complete this equation so that it is a Double displacement reaction
The complete equation to following equation to make a double replacement reaction is: Na2SO4 + BaCl2 = BaSO4 + 2NaCl.
What is a double displacement reaction.A double displacement reaction is the reaction that involves the replacement of two elements.
According to this question, barium sulfate (BaSO4) and sodium chloride are produced from the chemical equation given.
This clearly suggests that Sodium sulfate is the missing reactant, hence, the complete equation to following equation to make a double replacement reaction is:
Na2SO4 + BaCl2 = BaSO4 + 2NaCl.
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Which of the molecules obeys the octet rule? i. bh3 ii. no2 iii. sf6 iv. o3 v. pcl5 select one: a. choice i b. choice ii c. choice iii d. choice iv e. choice v
The molecule obeying the octet rule is option (D) O3.
According to the octet rule, an atom's outer shell or orbit needs to contain eight electrons for the molecule to be stable. Knowing the number of valence electrons in a molecule is made easier by Lewis structure. The electrons involved in bond-forming and non-bonding electron pairs are known as valence electrons.
Each oxygen molecule in ozone or O3 has six valence electrons.Due to the presence of three oxygen molecules, there are a total of 18 valence electrons (6*3=18). Therefore, the Ozone molecule has a total of 18 valence electrons accessible.
Therefore,The molecule obeying the octet rule is option (D) O3.
The resonance structure of O3 is given below;
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Principal energy levels describe regions of space where _____ may be found. they have values from n = 1, 2, 3 and so on. the greater the value of n, the _____ the average distance from the nucleus.
Principal energy levels describe regions of space where electrons may be found.
the greater the average distance from the nucleus.
The principal energy level of an electron is the shell or orbit in which the electron resides with respect to the nucleus. This level is represented by the principal quantum number n.
The principal quantum number n represents the total relative energy of each orbit. The energy level of each orbit increases as the distance from the nucleus increases. A set of orbitals with the same n value is often called the electron shell.
Only seven energy levels are required to contain all the electrons in any atom of any currently known element. As mentioned earlier, the energy associated with the energy level increases as the distance from the nucleus increases.
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- According to collision theory, what is not a factor that determines if two molecules will bind?
A. The direction the molecules are facing.
B. The speed the molecules are traveling.
C. The specific heat of the molecules.
D. What element the molecules are.
The factor which will not determines if two molecules will bind according to collision theory is the direction the molecules are facing
What is collision theory?Collision theory is a theory which describes of predicting the rate at which chemical reactions occurs between atoms and molecules of elements.
So therefore, the factor which will not determines if two molecules will bind according to collision theory is the direction the molecules are facing
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Taran wants to determine the mass of 7.3 moles of a compound. What additional information does Taran need
Answer: To determine the mass of the 7.3 moles of a compound Taran also needs to know the molar mass of the compound
Explanation: Multiply the atomic weight (from the periodic table) of each element by the number of atoms of that element present in the compound.
Add it all together and put units of grams/mole after the number.
It gives us the molar mass of the compound taken.
Multiply it with number of moles i.e., 7.3 moles, you will get the mass of the 7.3 moles of a compound.
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How many moles of sucrose are in 5.25x10^29 sucrose molecules?
Answer:
8.72×10^5
Explanation:
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Where do neuronal precursor cells that will eventually become hippocampal interneurons reside?
In the subgranular zone
Carbon has six protons; therefore, its mass number is six.
a. true
b. false
Answer:
B.) False
Explanation:
The mass number is determined by adding the number of protons and neutrons in an element's nucleus. Since carbon has 6 protons and 6 neutrons, the mass number is 12.
The atomic number is determined by the number of protons in an element's nucleus. Since carbon has 6 protons, the atomic number is 6.
Consider the chemical equilibrium of the reaction. NH4OH(aq) NH4 (aq) OH(aq) What will happen to the chemical equilibrium if NH4Cl is added to this solution
Answer:
hydrochloride acidic maby
Explanation:
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what is the name of pb(no3)2? explain how you determined the bond type and the steps you used to determine the naming convention for the compound.
The name of pb(no3)2 is Lead(II) nitrate.
Type of bond:pb(no3)2 is an ionic compound.
How to name ionic compound?
The name of an ionic compound is written as its cation followed by anionThe charge of cation should be written in Roman lettersThe net charge of ionic compounds is generally zeroName of pb(no3)2:
The charge of nitrate ion NO3 is -1. To find the charge of lead, we'll take it as x. Hence,
x+2(-1)=0
x=2
The charge of lead cation in this ionic compound is calculated as +2.
Therefore the name of pb(no3)2 is confirmed as Lead(II) Nitrate.
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A solution of ammonia NH3(aq) is at equilibrium. How would the equilibrium
change if NH4* were removed from the solution?
OA. [NH4*] would increase.
OB. [H*] would increase.
C. [NH] would decrease.
OD. [NH3] would increase.
Let's check the equation
[tex]\sf NH_3+H^+\leftrightharpoons NH_4^+H_2O[/tex]
As per Le ch a.tlers principle
Any external factor affecting the concentration or temperature still change the equilibriumSo
If we remove NH_4+
Water would increase
NH_3 would decreaseOption C
(iii) Calculate the volume of carbon dioxide at room temperature
and pressure that can be obtained from 30.0 g of glucose.
The combustion of 30.0 g of glucose at room temperature and pressure produces 24.0 L of carbon dioxide.
What is combustion?It is a reaction in which a substance burns with oxygen to form carbon dioxide and water.
Let's consider the combustion of glucose.
C₆H₁₂O₆ + 6 O₂ ⇒ 6 CO₂ + 6 H₂O
First, let's convert 30.0 g of glucose to moles using its molar mass.
30.0 g × 1 mol/180.16 g = 0.167 mol
The molar ratio of C₆H₁₂O₆ to CO₂ is 1:6. The moles of carbon dioxide produced are:
0.167 mol Glucose × (6 mol CO₂/1 mol Glucose) = 1.00 mol CO₂
1 mol of an ideal gas at room temperature and pressure occupies 24.0 L.
The combustion of 30.0 g of glucose at room temperature and pressure produces 24.0 L of carbon dioxide.
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How does the tundra contribute to a reduction of carbon dioxide on earth? how is climate change affecting the tundra’s ability to reduce carbon dioxide? (site 1)
This causes organic matter to decompose faster, releasing larger amounts of carbon dioxide into the atmosphere
As a result of climate change, tundra soils are thawing deeper and deeper and for a longer time in the upper layers of surface.
What is Tundra ?The tundra is a biome on the Earth that covers approximately 20% of its land mass, and it is almost exclusively located in the Northern Hemisphere.
It is an environment that helps in the regulation of the CO2 in the atmosphere, and it is one of the biggest natural CO2 sinks. The living organisms in the tundra, are using the CO2 for their needs, thus removing parts of it from the atmospherewhen they are no more, because the tundra is cold, and the decomposition is very slow, most of the CO2 remains trapped, and doesn't go into the atmosphere.Learn more about Tundra here:
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What do mitochondria do inside the cell?
Answer:
The most basic answer to this is that the mitochondria generates energy for the cell's power needs.
But... (elaborated in explanation.)
Explanation:
As you may know, the mitochondria is the powerhouse of cells.
The mitochondria can ALSO identify cell death, and determine which cells (dead) must be destroyed.
The mitochondria helps regulate calcium storage, but quickly absorbing calcium ions until needed.
And lastly, the mitochondria can also help generate heat. A process called proton leak. This is known as non-shivering thermogenesis.
What is different about atoms after a redox reaction has happened?
A. They have changed physical states.
B. Their oxidation states have changed.
C. The number of protons has changed.
D. They have higher electronegativities.
SUBMIT
Lidocaine is available in an ampule with 100 mg in 5 ml of solution. how many ml do you give to administer 65 mg?
Lidocaine is available in an ampule with 100 mg in 5 ml of solution. We need to give 3.25ml to administer 65mg.
Lidocaine is an anesthetic that has the power to neutralize neuromal membranes.
Given data:
Amount desired (D) = 65 g
Amount on hand (H) = 100 mg
Quantity = 5 mL
Plug in what you know into the formula and simplify.
[tex]\frac{Amount desired}{Amount in hand}[/tex] × quantity
[tex]\frac{65}{100}[/tex] × 5
0.65 × 5 = 3.25ml
Therefore, When Lidocaine is available in an ampule with 100 mg in 5 ml of solution. We need to give 3.25ml to administer 65mg.
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The chemotherapy drug cis-platin, Pt(NH3)2Cl2, is prepared via the chemical reaction shown below.
(NH4)2PtCl4 + NH3 ---> Pt(NH3)2Cl2 + NH4Cl
What volume of 0.400 M NH3 (ammonia) is required to completely react with 25.00 mL of a 0.100 M solution of the platinum-containing starting compound, (NH4)2PtCl4?
Answer:
12.5 mL NH₃
Explanation:
To find the volume of NH₃, you need to (1) find the moles (NH₄)₂PtCl₄ (using the molarity equation), then (2) convert moles (NH₄)₂PtCl₄ to moles NH₃ (via mole-to-mole ratio from balanced equation, and then (3) find the volume NH₃ (using the molarity equation).
(Step 1)
25.00 mL / 1,000 = 0.025 L
Molarity = moles / volume (L)
0.100 M = moles / 0.025 L
0.0025 = moles (NH₄)₂PtCl₄
(Step 2)
The unbalanced equation:
(NH₄)₂PtCl₄ + NH₃ ----> Pt(NH₃)₂Cl₂ + NH₄Cl
Reactants: 2 nitrogen, 11 hydrogen, 1 platinum, 4 chlorine
Products: 2 nitrogen, 10 hydrogen, 1 platinum, 3 chlorine
The balanced equation:
(NH₄)₂PtCl₄ + 2 NH₃ ----> Pt(NH₃)₂Cl₂ + 2 NH₄Cl
Reactants: 3 nitrogen, 14 hydrogen, 1 platinum, 4 chlorine
Products: 2 nitrogen, 14 hydrogen, 1 platinum, 4 chlorine
0.0025 moles (NH₄)₂PtCl₄ 2 moles NH₃
---------------------------------------- x ------------------------------ = 0.0050 moles NH₃
1 mole (NH₄)₂PtCl₄
(Step 3)
Molarity = moles / volume (L)
0.400 M = 0.0050 moles / volume
(0.400 M) x volume = 0.0050 moles
volume = 0.0125 L NH₃
0.0125 L x 1,000 = 12.5 mL NH₃
Which is the site of gaseous exchange in the lungs?
Write the relationship between displacement, velocity and time?
Explanation:
1. The gaseous exchange in the lungs occurs in the alveoli. They are tiny air sacs at the end of the bronchioles (tiny branches of air tubes in the lungs). The alveoli are where the lungs and the blood exchange oxygen and carbon dioxide during the process of breathing in and breathing out.
By now you should realize that having an octet of electrons on a central atom is critical for a molecule to be stable. Would you expect NO and NO2 to be stable molecules
NO is a stable compound
The octet rule describes an atom's propensity to favor eight electrons in its valence shell. Atoms with fewer than eight electrons are more likely to interact with one another and create a more stable compound.
The majority of other odd-electron molecules, including NO, are highly chemically reactive and stable compounds. The second breach of the octet rule is the presence of molecules lacking electrons. Less than eight electrons are positioned around each atom in these stable compounds.
The overall molecular orbital arrangement of NO will be as follows, nitrogen has 7 electrons and oxygen has 8 electrons, according to the molecular orbital theory.
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A company sells a natural medicine with plant ingredients to help treat dementia, a disease in which people have a hard time remembering things. the natural ingredients in the medicine are most likely from which type of plant?
The type of plant should be ginkgo.
Ginkgo biloba is a popular herbal supplement used to improve memory and prevent dementia, presumably due to its antioxidant properties or anti-amyloid aggregation effects.
What is Dementia?Dementia is a term used to describe when a person's loss of certain behavioral abilities, such as remembering, thinking, and reasoning, interferes with their daily activities and life.
Dementia occurs when neurons in the brain stop functioning, lose their ability to communicate with other cells in the brain, and die. When people develop dementia, they may have problems with a variety of cognitive functions.
What Are Ginkgo Trees Used For?Aside from its decorative aspects, ginkgo biloba is a medical herb with numerous benefits. The tree is frequently used to treat a variety of ailments, including:
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What could the fourth quantum number of a 3p3 electron be?
A. ms=-1/2
B. ms=-1
C. ms=+1
D. ms=0
In sharp contrast to elimination reactions, addition reactions are generally favored at ______________________, because ________ is more likely to be negative at such temperatures.
In sharp contrast to elimination reactions, addition reactions are generally favored at low temperature, because enthalpy term is more likely to be negative at such temperatures.
What is Addition Reaction ?An addition reaction is an organic reaction occur when two or more molecules combine to form a larger molecule without the loss of any atoms present in reactant. Addition reaction is favored at low temperature.
What is Elimination Reaction ?Elimination reaction is a type of organic reaction where many atoms either in groups or pairs are removed from a molecule. Elimination reaction is favored at high temperature.
Thus from the above conclusion we can say that In sharp contrast to elimination reactions, addition reactions are generally favored at low temperature, because enthalpy term is more likely to be negative at such temperatures.
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9. What is the final concentration when 420 mL of a 12.0 mol/L sodium hydroxide solution is diluted to 2.0 L?
Show your work and explain each step.
Answer: 2.52 M
Explanation:
The product of molarity (moles/litre) and volume in litres yields moles, and the numbers of moles in two solutions means dilute and concentrated are equal, which is expressed by the following equation:
[tex]M_1V_1=M_2V_2[/tex]
[tex]$$Given that\\M $1=12.0 \mathrm{M}$ or mole $/ \mathrm{L}$\\$\mathrm{V} 1=420 \mathrm{ml}$\\$\mathrm{M} 2=$ ?\\$\mathrm{V} 2=2.0 \mathrm{~L}$ or $2000 \mathrm{ml}$\\\\$\mathrm{M} 1 \mathrm{~V} 1=\mathrm{M} 2 \mathrm{~V} 2$\\$\mathrm{M} 2=\mathrm{M} 1 \mathrm{~V} 1 / \mathrm{V} 2$\\$=12.0 * 420 / 2000$\\$=2.52 \ \mathrm{M}$[/tex]