Answer:
is this a poem or something?
What is so important about DNA? Select all correct answers.
A. DNA is found in all organisms and carries instructions to build those organisms
B. DNA found in one organism probably shares similar instructions found in another species
C. DNA is composed of only four bases that repeat in a sequence that is different for each
species
D. Some organisms don't actually have DNA
E. The DNA of each organism is made out of different types of chemicals
Answer:
A and C
Explanation:
DNA is what makes up you and me and DNA is composed of four bases adenine, guanine, thymine, and cytosine. The others are not true.
5 Facts about cell division
What is the mass of 925.4 L of hydrogen gas at STP?
Answer:
If this is an idea gas then 1mol takes up 22.4L.
So, knowing how many L you have you can figure out how many mole syou have by doing a simple equation:
[tex]\frac{1mol}{y} =\frac{22.4L}{925.4L}[/tex]
Solve for y.
Then, since you know how many moles you have use the ptable https://ptable.com/#Properties to figure out the mass in grams.
NOTE: The ptable tells you that 1mol of H = 1g.....so this should be an easy calculation :) enjoy
What are several ways that humans destroy an ecosystem?
Answer:
Some human activities that cause damage (either directly or indirectly) to the environment on a global scale include population growth, overconsumption, overexploitation, pollution, and deforestation, to name but a few.
Explanation:
Hope this helped!!!
How many moles are in 1.3 x1023 atoms of He?
Answer:
he ans she and he and she but she was he so how was he
Explanation:
There are 4 mg of lead present in 2000 g of a water sample. What is the
concentration of lead in m?
Answer: 130 ppm Pb
Explanation:
We use parts per million to express the concentrations of solutions that contain very, very small amounts, often called trace amounts, of a given solute.
More specifically, a solution's concentration in parts per millions tells you the number of parts of solute present for every
10
6
=
1
,
000
,
000
parts of solution. You can thus say that a
1 ppm
solution will contain exactly
1 g
of solute for every
10
6
g
of solution.
In your case, you know that you have
38
mg Pb
⋅
1 g
10
3
mg
=
3.8
⋅
10
−
2
.
g Pb
in exactly
300.0 g
=
3.000
⋅
10
2
.
g solution
This means that you can use this known composition as a conversion factor to scale up the mass of the solution to
10
6
g
10
6
g solution
⋅
3.8
⋅
10
−
2
.
g Pb
3.000
⋅
10
2
g solution
=
130 g Pb
Since this represents the mass of lead present in exactly
10
6
g
of solution, you can say that the solution has a concentration of
concentration
ppm
=
130 ppm Pb
−−−−−−−−−−−−−−−−−−−−−−−−−−−−
The answer is rounded to two sig figs, the number of sig figs you have for the mass of lead present in the sample.
phosphorous can be prepared by electrolysis of an aqueous phosphate solution
Phosphorus can be prepared by electrolysis of an aqueous phosphate solution. The method of extraction of phosphorus from the phosphate solution involves the process of electrolysis.
The electrolysis process is defined as a process in which a chemical reaction is caused by an electric current passing through an electrolyte. The electrolysis of the aqueous solution of phosphate is the process in which phosphorus is extracted from the solution. The procedure of electrolysis of an aqueous phosphate solution is as follows: Two electrodes are placed into the phosphate solution, one is the anode (positive electrode) and the other is the cathode (negative electrode). The anode is made up of graphite and the cathode is made up of mercury. A direct current is then passed through the solution. When the current is passed, it causes the oxygen to be released at the anode, which combines with graphite to produce carbon dioxide.
In addition, at the cathode, hydrogen gas is released along with mercury, and the mercury is mixed with the phosphorus to produce an alloy. The mixture is then filtered, and the impurities are removed with the help of hydrochloric acid. The obtained phosphorus is solid and can be melted and moulded into sticks. The process of electrolysis is a good method for the extraction of phosphorus from aqueous solutions and the process is economically viable. This process is also good because the phosphate solution can be obtained from rock phosphates, and this process is a good alternative to the use of non-renewable phosphorus sources. The main advantages of this process are that it is cost-effective, does not require high temperatures, and is environmentally friendly.
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Pls no links can someone pls tell me what to put to fill in the blanks please someone?????
Answer: you go down by your key bad and use those arrows
Explanation:
For the sequential deprotonations of a polyprotic acid, the equilibrium constants will typically: Select the correct answer below: a. have roughly the same values b. increase with each successive ionization c. decrease with successive ionization d. impossible to predict
For the sequential deprotonations of a polyprotic acid, the equilibrium constants typically decrease with successive ionization. Therefore, the correct answer is option c: decrease with successive ionization.
For the sequential deprotonations of a polyprotic acid, the equilibrium constants typically decrease with each successive ionization. This is due to several factors. As protons are successively removed, the remaining ions become more negatively charged, leading to increased electrostatic repulsion and reduced stability. Additionally, the loss of each proton becomes energetically less favorable as the acid becomes more negatively charged. Furthermore, the availability of electrons for stabilization through resonance or induction decreases as protons are lost. These factors contribute to a decrease in the strength of the subsequent acids formed, leading to lower equilibrium constants for each successive ionization.
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a sample of gas at 25.0 c has a volume of 11.0 L and exerts a pressure of 660.0 mmHg. how many moles of gas are in the sample
Answer: 0.391
Explanation:
Ideal gas law is valid only for ideal gas not for vanderwaal gas. Therefore, 0.38moles of gas are in the sample. Ideal gas is a hypothetical gas.
What is ideal gas equation?Ideal gas equation is the mathematical expression that relates pressure volume and temperature. There is no force of attraction between the particles.
Mathematically the relation between Pressure, volume and temperature can be given as
PV=nRT
where,
P = pressure of gas sample = 660.0mmHg=0.86atm
V= volume of gas sample =11.0 L
n =number of moles of gas sample=?
T =temperature of gas =298K
R = Gas constant = 0.0821 L.atm/K.mol
Substituting all the given values, we get
0.86atm×11.0 L =n× 0.0821×298
On calculation we get
9.46=n×24.4
number of moles of sample=0.38moles
Therefore, 0.38moles of gas are in the sample.
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drive the equilibrium in the reaction mixture towards the product.
To drive the equilibrium in the reaction mixture towards the product, manipulate the reaction conditions and adjust the reaction parameter.
How can the reaction conditions be optimized to favor the product formation?Adjusting reaction conditions to drive the equilibrium towards the desired product. By manipulating various factors such as temperature, pressure, concentration, and catalysts, it is possible to shift the equilibrium in a chemical reaction towards the product side. Altering these parameters can impact the forward and backward reaction rates, ultimately favoring the formation of the desired product.
For example, increasing the temperature may promote an endothermic reaction, while reducing the pressure or adjusting the concentration of reactants can help alleviate the impact of Le Chatelier's principle.
Additionally, introducing a catalyst can provide an alternative reaction pathway with lower activation energy, facilitating the production of the desired product. Understanding these principles and their application allows for strategic control over the equilibrium and the optimization of reaction conditions to maximize product yield.
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Use the Ksp values in section 4.2 to calculate the pH at which a precipitate of iron(III) hydroxide will begin to dissolve. Assume that the concentration of iron in the solution is 0.1 M. b. Describe how you could use pH control to separate lead and iron if they were both precipitated as their hydroxides. Hint: How could pH be used to dissolve one of the hydroxide precipitates but not the other?
To selectively dissolve iron(III) hydroxide while leaving lead(II) hydroxide unaffected, pH control is used by adjusting the solution to be more basic, exploiting the difference in solubility behavior of the two hydroxides at different pH levels.
To calculate the pH at which a precipitate of iron(III) hydroxide will begin to dissolve, we need to use the solubility product constant (Ksp) for iron(III) hydroxide[tex](Fe(OH)_{3} )[/tex] and the concentration of iron in the solution.
b. To separate lead and iron if they were both precipitated as their hydroxides, pH control can be employed. By adjusting the pH, one of the hydroxide precipitates can be selectively dissolved while the other remains insoluble.
The solubility of a metal hydroxide is typically dependent on the pH of the solution due to the formation of hydroxide complexes or the presence of competing species.
For example, lead(II) hydroxide [tex](Pb(OH)_{2} )[/tex]has low solubility in neutral or slightly basic conditions, while iron(III) hydroxide[tex](Fe(OH)_{3} )[/tex]is more soluble at higher pH values.
Therefore, if both lead and iron hydroxide precipitates are formed, adjusting the pH to be more basic will selectively dissolve the iron(III) hydroxide precipitate while leaving the lead(II) hydroxide precipitate relatively unaffected.
This separation can be achieved by adding a basic solution, such as sodium hydroxide (NaOH), to increase the pH. The lead(II) hydroxide will remain insoluble while the iron(III) hydroxide will dissolve into solution due to the formation of soluble hydroxide complexes.
By carefully controlling the pH, the two metal hydroxide precipitates can be separated.
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The chemical equation below is correctly balanced.
4 Al + 3 O2 → 2 Al2O3
How many moles of Al2O3 will be formed when 27 grams of Al reacts completely with O2?
Answer:
0.35moles
Explanation:
when 156g of Al reacts with 2molesof Al2O3 then 27g of Al reacts with what then u cross multiply and solve ur answer
0.35moles of Al[tex]_2[/tex]O[tex]_3[/tex] will be formed when 27 grams of Al reacts completely with O[tex]_2[/tex]. A mole consists of precisely 6.022× 10²³particles.
What is mole?A mole is just a measuring scale. In reality, it's one of the International System of Units' seven foundation units (SI). When already-existing units are insufficient, new ones are created. The levels at which chemical reactions frequently occur exclude the use of grams, yet utilizing actual numbers of atoms, molecules, or ions would also be unclear.
A mole consists of precisely 6.022× 10²³particles. The "particles" might be anything, from tiny things like electrons and atoms to enormous things like stars or elephants.
4 Al + 3 O[tex]_2[/tex] → 2 Al[tex]_2[/tex]O[tex]_3[/tex]
moles of aluminium = 27 /26=1.03moles
The mole ratio between Al and Al[tex]_2[/tex]O[tex]_3[/tex] is 2:1
mole of Al[tex]_2[/tex]O[tex]_3[/tex]= 0.35moles
Therefore, 0.35moles of Al[tex]_2[/tex]O[tex]_3[/tex] will be formed when 27 grams of Al reacts completely with O[tex]_2[/tex].
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if 5.00g nacl (molar mass = 58.44 g/mol) was reacted with 10.0ml of 5m h2so4 what is the limiting reactant in this reaction?
The limiting reactant in the reaction, given that 5.00 g of NaCL reacted with 10.0 mL of 5 M H₂SO₄ is NaCl
How do i determine the limiting reactant?First, we shall obtain the mole of 5.00 g of NaCl. Details below:
Mass of NaCl = 5 grams Molar mass of NaCl = 58.44 g/mol Mole of NaCl =?Mole of NaCl = mass / molar mass
= 5 / 58.44
= 0.09 mole
Next, we shall obtain the mole of 10.0 mL of 5 M H₂SO₄. Details below:
Volume = 10 mL = 10 / 1000 = 0.01 LMolarity = 5 MMole of H₂SO₄ =?Mole of H₂SO₄ = molarity × volume
= 5 × 0.01
= 0.05 mole
Finally, we shall determine the limiting reactant. Details below:
2NaCl + H₂SO₄ -> Na₂SO₄ + 2HCl
From the balanced equation above,
2 moles of NaCl reacted with 1 mole of H₂SO₄
Therefore,
0.09 mole of NaCl will react with = (0.09 × 1) / 2 = 0.045 mole of H₂SO₄
We can see from the above that only 0.045 mole of H₂SO₄ out of 0.05 mole is needed to react completely with 0.09 mole of NaCl.
Thus, we can conclude that the limiting reactant for the reaction is NaCl
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what is the atomic weight of Na?
Answer:
22.989769 u
Explanation:
The atomic weight of any atom can be found by multiplying the abundance of an isotope of an element by the atomic mass of the element and then adding the results together. This equation can be used with elements with two or more isotopes: Carbon-12: 0.9889 x 12.0000 = 11.8668. Carbon-13: 0.0111 x 13.0034 = 0.1443.
Use the following balanced equation: 2H2 + O2 ---> 2H2O If you start with 24 molecules of hydrogen gas, how marry molecules of oxygen gas do you need? ___ molecules How many molecules of water are made from the amount of starting materials described above? ____ molecules
The number of water molecules formed from the given starting materials is 3.99 × 10-21 molecules.
Balanced equation is:2H2 + O2 ---> 2H2OIf you start with 24 molecules of hydrogen gas, how many molecules of oxygen gas do you need?From the above-balanced chemical equation, we can see that 2 molecules of hydrogen react with 1 molecule of oxygen gas to form 2 molecules of water.Thus, to form 24 molecules of hydrogen gas, we need 12 molecules of oxygen gas. How many molecules of water are made from the amount of starting materials described above?To determine the number of molecules of water formed from the starting materials, we have to determine the limiting reagent. The reactant that gives the least amount of product is called the limiting reagent.To determine the limiting reagent, we can use the concept of mole. The number of moles of a substance is determined by dividing the given mass of the substance by its molar mass.Therefore, the given information of the number of molecules is required to be converted to the number of moles.Number of molecules of hydrogen gas = 24The number of moles of hydrogen gas = (24/6.023 × 1023) = 3.989 × 10-21The number of moles of oxygen gas = (3.989 × 10-21)/2 = 1.995 × 10-21Since there are only 1.995 × 10-21 moles of oxygen gas, it will get consumed in the reaction before all the hydrogen gas is consumed. Therefore, oxygen gas is the limiting reagent.The number of moles of water formed is given by the stoichiometric coefficient of water in the balanced equation, which is 2.Number of molecules of water formed from 24 molecules of hydrogen and 12 molecules of oxygen = 2 × (1.995 × 10-21) = 3.99 × 10-21Therefore, the number of water molecules formed from the given starting materials is 3.99 × 10-21 molecules.
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The Ka values for nitrous acid (HNO2) and hypochlorous (HClO) acid are 4.5×10−4 and 3.0×10−8, respectively.
Part A: Which one would be more suitable for use in a solution buffered at pH = 7.0?
Nitrous acid ([tex]HNO_2[/tex]) would be more suitable for use in a solution buffered at pH 7.0.
To determine which acid, nitrous acid ([tex]HNO_2[/tex]) or hypochlorous acid (HClO), is more suitable for use in a solution buffered at pH 7.0, we need to compare their pKa values. The pKa is related to the Ka (acid dissociation constant) by the equation:
pKa = -log10(Ka)
Let's calculate the pKa values for nitrous acid and hypochlorous acid using the given Ka values:
For nitrous acid ([tex]HNO_2[/tex]):
pKa = -log10(4.5×[tex]10^{(-4)[/tex])
= -log10(4.5) - log10([tex]10^{(-4)[/tex])
= -log10(4.5) + 4
For hypochlorous acid (HClO):
pKa = -log10(3.0×[tex]10^{(-8)[/tex])
= -log10(3.0) - log10([tex]10^{(-8)[/tex])
= -log10(3.0) + 8
Comparing the pKa values, we find:
pKa ([tex]HNO_2[/tex]) = -log10(4.5) + 4
pKa (HClO) = -log10(3.0) + 8
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based on the calculations performed in this experiment, would the same mass of a solute with a significantly higher molar mass have a larger or smaller effect on the boiling point elevation?
Based on the calculations performed in this experiment, the same mass of a solute with a significantly higher molar mass would have a larger effect on the boiling point elevation. As a result, the same mass of a solute with a higher molar mass will have a greater effect on the boiling point elevation.
Boiling point elevation is a thermodynamic phenomenon that occurs when the boiling point of a solvent (a substance that dissolves a solute to create a solution) is increased by adding another substance, the solute, to it. When a solute is added to a solvent, it lowers the freezing point and raises the boiling point of the solvent, which is known as the boiling point elevation.The formula for boiling point elevation is: ∆Tb = Kbm
Here, ∆Tb is the boiling point elevation, Kb is the molal boiling point elevation constant, and m is the molality of the solution. To understand this, let us take an example: Suppose a solution containing 1.0 mol of sodium chloride (NaCl) is dissolved in 1.0 kg of water. The molality of the solution is 1.0 mol / 1.0 kg = 1.0 m. In addition, the Kb for water is 0.51 °C/molal, which means that the boiling point elevation is 0.51 °C when the molality of the solution is 1.0 mol/kg.So, the boiling point of the solution will be raised by 0.51 °C, which can be calculated using the above formula.Calculation performed in this experiment:Boiling point elevation = ΔTb = Kb . mTherefore, based on the above formula, the boiling point elevation is directly proportional to the molality of the solution, which, in turn, is directly proportional to the number of moles of solute in the solution. Furthermore, the number of moles of solute is proportional to the mass of the solute (in grams) divided by its molar mass (in grams/mol).So, if a solute with a significantly higher molar mass is added to the solvent, it will have a larger effect on the boiling point elevation. As a result, the same mass of a solute with a higher molar mass will have a greater effect on the boiling point elevation.
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Benadryl, C17H21NO, is an over-the-counter drug used to treat allergy symptoms. If each dose of Benadryl contains 5.89 x 10^19molecules of Benadryl, how many moles is this equal to?
Answer:
9.78x10^(-5) mol
Explanation:
To convert molecules to moles, divide the # of molecules by 6.02x10^23.
5.89x10^19 / 6.02x10^23 = 9.78x10^(-5) mol
1. Find the molarity of 2.39 g Lif in 450 mL of water
Answer:
0.205M
Explanation:
Molarity is an unit of concentration used in chemistry defined as the ratio between moles of solute (In this case, LiF) and liters of solution.
To solve this question, we must find the moles of LiF and the liters of the solution:
Moles LiF -Molar mass: 25.939g/mol-:
2.39g * (1mol / 25.939g) = 0.0921moles
Liters solution:
450mL * (1L / 1000mL) = 0.450L
Molarity is:
0.0921 moles / 0.450L =
0.205MAccording to the following reaction, how many moles of mercury(II) oxide are necessary to form 0.896 moles oxygen gas? mercury(II) oxide (s) mercury (l) + oxygen (g) ___?___moles mercury(II) oxide
We require 0.896 moles of HgO to produce 0.896 moles of O2.
The balanced chemical equation for the given reaction is;HgO(s) → Hg(l) + O2(g)We can calculate the number of moles of HgO(s) required to produce 0.896 moles of O2(g) using stoichiometry.To use stoichiometry we need to know the mole ratio of O2 to HgO in the above reaction.Based on the balanced chemical equation, the ratio of HgO to O2 is 1:1.This means that 1 mole of HgO will produce 1 mole of O2.Therefore, the number of moles of HgO required to produce 0.896 moles of O2 is also 0.896 moles.150 words explanation:To calculate the number of moles of HgO required to produce 0.896 moles of O2 we can use the mole ratio of the two compounds in the balanced chemical equation.HgO(s) → Hg(l) + O2(g)From the equation, the ratio of HgO to O2 is 1:1. This means that 1 mole of HgO will produce 1 mole of O2.If we have 0.896 moles of O2, we will require the same number of moles of HgO to produce the O2. Therefore, we require 0.896 moles of HgO to produce 0.896 moles of O2.
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a sample of nuclear waste cesium 137 has a half life of approximately 30 years. if there are 88.44g of cesium 137 produced, how many years until the waste is deemed safe?
The time until nuclear waste cesium 137 is deemed safe can be determined by calculating the number of half-lives required for the amount of cesium 137 to decrease to a safe level.
The half-life of cesium 137 is approximately 30 years. This means that every 30 years, the amount of cesium 137 will be reduced by half. To determine the time until the waste is deemed safe, we need to calculate the number of half-lives required for the amount of cesium 137 to decrease to a safe level. Given that there are 88.44 g of cesium 137 initially, we can calculate the number of half-lives using the formula:
Number of Half-Lives = (ln(initial amount) - ln(final amount)) / ln(0.5)
Using the given values, we can substitute the initial amount as 88.44 g and the final amount as the safe level of cesium 137 (determined by regulatory standards). By solving the equation, we can find the number of half-lives required. Once we have the number of half-lives, we can multiply it by the half-life of cesium 137 (30 years) to determine the total time until the waste is deemed safe. It is important to note that the specific safe level of cesium 137 is not provided in the question. Regulatory bodies and authorities establish safe levels based on various factors, such as environmental and health considerations.
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calculate the molar solubility of pbi2 in aqueous solution. use the ksp you obtained for this experiment.
The molar concentration of iodide ion (I⁻) in a saturated PbI₂ solution is 3 x 10⁻³ M.
To determine the molar concentration of iodide ion (I⁻) in a saturated PbI₂ solution, we need to consider the stoichiometry of the dissolution reaction of PbI₂ and use the solubility product constant (Ksp) for PbI₂.
The balanced equation for the dissolution of PbI₂ is:
PbI₂(s) ⇌ Pb²⁺(aq) + 2I⁻(aq)
According to the stoichiometry of the balanced equation, every 1 mole of PbI₂ dissociates to produce 2 moles of iodide ions (I⁻). Therefore, the molar concentration of iodide ions can be calculated by multiplying the molar solubility of PbI₂ by 2.
Given that the molar solubility of PbI₂ is 1.5 x 10⁻³ M, the molar concentration of iodide ion in a saturated PbI₂ solution is:
2 x (1.5 x 10⁻³ M) = 3 x 10⁻³ M
Therefore, the molar concentration will be 3 x 10⁻³ M.
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--The given question is incomplete, the complete question is
"The Molar Solubility Of PbI₂ Is 1.5 X 10⁻³ M.A/ What Is The Molar Concentration Of Iodide Ion In A Saturated PbI₂ Solution?"--
Indicate whether each of the following statements is characteristic of an acid, a base, or both:
a. has a sour taste
b. neutralizes bases
c. produces ions in water
d. is named barium hydroxide
e. is an electrolyte
a. has a sour taste - this statement is for acid.
b. neutralizes bases - this statement is for acid.
c. produces ions in water - this statement is for both acid and base.
d. is named barium hydroxide - this statement is for base
e. is an electrolyte - this statement is for both acid and base.
What is an acid?An acid, any substance that in water solution tastes sour, changes the colour of certain indicators.
Acids are ionic compounds that, when dissolved in water, produce positive hydrogen ions ( H⁺ ).
We will indicate whether each of the following statements is characteristic of an acid, a base, or both as follows;
a. has a sour taste - this statement is for acid.b. neutralizes bases - this statement is for acid.c. produces ions in water - this statement is for both acid and base.d. is named barium hydroxide - this statement is for basee. is an electrolyte - this statement is for both acid and base.Learn more about characteristics of acid and base here: https://brainly.com/question/14997571
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a) 0.45 g of hydrogen chloride (HCl) is dissolved in water to make 6.0 L of solution. What is the pH of the resulting hydrochloric acid solution? Express the pH numerically to two decimal places.
b) 0.20 g of sodium hydroxide (NaOH) pellets are dissolved in water to make 2.0 L of solution. What is the pH of this solution?
The hydrochloric acid solution with 0.45 g of HCl dissolved in 6.0 L of water has a pH of 2.70. The sodium hydroxide solution created by dissolving 0.20 g of NaOH pellets in 2.0 L of water has a pH of 11.40.
The pH of a hydrochloric acid solution can be determined by calculating the concentration of H+ ions in the solution. In this case, 0.45 g of hydrogen chloride (HCl) is dissolved in 6.0 L of water. To find the concentration, we need to convert grams to moles. The molar mass of HCl is 36.46 g/mol, so 0.45 g is equal to 0.012 moles. Dividing this by the volume of the solution, we get a concentration of approximately 0.002 M. Since HCl is a strong acid, it dissociates completely in water, resulting in an equal concentration of H+ ions. Therefore, the pH of the hydrochloric acid solution is -log(0.002) = 2.70. On the other hand, sodium hydroxide (NaOH) is a strong base that dissociates completely in water to form hydroxide ions (OH-). To find the pH of the sodium hydroxide solution, we need to determine the concentration of OH- ions. Similar to the previous example, we first convert the mass of NaOH to moles. The molar mass of NaOH is 39.997 g/mol, so 0.20 g is equal to 0.005 moles. Dividing this by the volume of the solution, we get a concentration of 0.0025 M. Since NaOH fully dissociates, the concentration of OH- ions is also 0.0025 M. To find the pOH of the solution, we take the negative logarithm of the concentration: -log(0.0025) = 2.60. Finally, we can find the pH by subtracting the pOH from 14: 14 - 2.60 = 11.40.
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A large doublet and a small septet pattern in ¹H NMR is usually indicative of a(n)
A. ethyl group.
B. propyl group.
C. isopropyl group.
D. phenyl group.
The answer is B. propyl group.A large doublet and a small septet pattern in ¹H NMR spectroscopy indicate the presence of a propyl group in the molecule being analyzed.
In ¹H NMR (proton nuclear magnetic resonance) spectroscopy, the number and arrangement of signals in the spectrum provide information about the chemical environment and connectivity of hydrogen atoms in a molecule. A large doublet and a small septet pattern in ¹H NMR is characteristic of a propyl group.
A propyl group consists of three carbon atoms connected in a chain, with a hydrogen atom attached to each carbon atom. The large doublet arises from the neighboring hydrogens (vicinal protons) on the middle carbon atom, which split the signal into two peaks of equal intensity. The small septet arises from the hydrogens on the two terminal carbon atoms, which split the signal into seven peaks with intensity ratios of 1:6:6:6:6:6:1.
An ethyl group (A) consists of two carbon atoms and does not exhibit a septet pattern. An isopropyl group (C) consists of three carbon atoms but has a different arrangement of hydrogens, leading to a different splitting pattern in the NMR spectrum. A phenyl group (D) is an aromatic ring and typically exhibits different patterns in the NMR spectrum.
A large doublet and a small septet pattern in ¹H NMR spectroscopy indicate the presence of a propyl group in the molecule being analyzed. This pattern arises from the chemical shifts and splitting of hydrogens within the propyl group's carbon chain.
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Please Help ASAP!!! Will mark Brainliest!!!
A 35 kg child is standing in a 70 kg boat resting on the water. The child jumps forward, away from the boat, pushing with a force of 500 N. After the jump, the boat moves backward.
What does this scenario show?
A. The boat does not exert a force to balance the 500 N force, causing the boat to move.
B. The water creates a frictionless surface, causing the boat to move without an action force.
C. The boat has a greater mass than the child but reacts to an action force.
D. The water beneath the boat absorbs the 500 N force but keeps the boat afloat.
Answer:
A
Explanation:
the boat does not have a force to counter act the boys it must give which means it moves cause it is one something that is not as dense as the boy (I THINK)
the half-life of plutonium-239 is 24,300 years. if a nuclear bomb released 8 kg of this isotope, how many grams of plutonium-239 would be left after 72,900 years?
To calculate the amount of plutonium-239 remaining after 72,900 years, we need to determine the number of half-lives that have passed. Given that the half-life of plutonium-239 is 24,300 years and 8 kg of this isotope was initially released, we can use the half-life formula to find the answer.
The number of half-lives can be calculated by dividing the total time elapsed (72,900 years) by the half-life of the isotope (24,300 years). In this case, the number of half-lives would be 72,900 years / 24,300 years = 3 half-lives. The remaining amount of plutonium-239 can be calculated by multiplying the initial amount (8 kg) by (1/2) raised to the power of the number of half-lives. Each half-life reduces the amount of plutonium-239 to half its previous value.
Remaining amount = initial amount × (1/2)^(number of half-lives)
Remaining amount = 8 kg × (1/2)^3
Remaining amount = 8 kg × (1/8)
Remaining amount = 1 kg
Therefore, after 72,900 years, there would be 1 kg (1000 grams) of plutonium-239 remaining from the initially released 8 kg.
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what is the molarity of 3.0 L solution containing 250 g of Nal
Answer: C. 0.57 M
Explanation:
Molarity= Moles/Vol
a system does 566 kj of work and loses 246 kj of heat to the surroundings. what is the change in internal energy, δ , of the system? note that internal energy is symbolized as δ in some sources.
The change in internal energy (ΔU) of the system is 320 kJ.
The change in internal energy (ΔU) of a system can be calculated using the first law of thermodynamics, which states that the change in internal energy of a system is equal to the heat added to the system minus the work done by the system:
ΔU = Q - W
where ΔU is the change in internal energy, Q is the heat added to the system, and W is the work done by the system.
In this case, the system does 566 kJ of work (W = -566 kJ) and loses 246 kJ of heat to the surroundings (Q = -246 kJ). The negative sign indicates that the work is done by the system and the heat is lost by the system.
Substituting the values into the equation:
ΔU = -246 kJ - (-566 kJ)
= -246 kJ + 566 kJ
= 320 kJ
Therefore, the change in internal energy (ΔU) of the system is 320 kJ.
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