Explanation:
From the question given above, the following data were obtained:
Half-life (t½) = 9.7 days
Time (t) = 60 days
Percentage remaining after 60 days =?Next, we shall determine the number of half-lives that has elapsed. This can be obtained as follow:
Half-life (t½) = 9.7 days
Time (t) = 60 days
Number of half-lives (n) =?
n = t / t½
n = 60 / 9.7Finally, we shall determine the percentage remaining. This can be obtained as follow:
Let the original amount be N₀
Let the amount remaining be N
Number of half-lives (n) = 60 / 9.7
N = N₀ / 2ⁿ
Divide both side by N₀
N/N₀ = 1/2ⁿ
N/N₀ = 1 / 2⁽⁶⁰÷⁹•⁷⁾
N/N₀ = 0.0137
Multiply by 100 to express in percentage
N/N₀ = 0.0137 × 100
N/N₀ = 1.37%Therefore, the percentage remaining after 60 days is 1.37%
NOTE; N/N₀ is the fraction remaining.Learn more: https://brainly.com/question/14883322
Ethylene glycol (C2H6O2) is mixed with water to make auto engine coolants. How many grams of C2H6O2 are in 5.00 L of a 6.00 M aqueous solution
Answer:
1860g.
Explanation:
It is known that the molar mass of C2H6O2 is 62.08 g/mol.,
Now to solve for the number of moles of solute, one must multiply both
sides by the volume:
moles of solute = (6.00 M)(5.00 L) = 30.0 mol
Notice since the definition of molarity is mol/L, the
product M × L gives mol, a unit of amount.
Use the molar mass of C3H8O3, one can convert mol to g:
Mass m =30 mol × 62.08 g/mol
m = 1860g.
Hence, there are 1,860 g of C2H6O2 in the specified amount of
engine coolant.
In aqueous solution the Ni2" ion forms a complex with four ammonia molecules. Write the formation constant expression for the equilibrium between the hydrated metal ion and the aqueous complex. Under that, write the balanced chemical equation for the first step in the formation of the complex K,=________.
Answer:
The correct equation is "[tex]\frac{[Ni(H_2O)_3 (NH_3)]^{2+}}{[Ni(H_2O)_4]^{2+} [NH_3]}[/tex]".
Explanation:
According to the question,
Throughout an aqueous solution, [tex]Ni^{2+}[/tex] exist as [tex][Ni(H_2O)_4]^{2+}[/tex]
So,
⇒ [tex][Ni(H_2O)_4]^{2+} + 4NH_3 \rightleftharpoons [Ni(NH_3)_4]^{2+} + H_2O[/tex]
⇒ [tex]K_f = \frac{[Ni(NH_3)_4]^{2+}}{[Ni(H_2O)_4^{2+}] [NH_3]^4}[/tex]
Here, we have excluded [tex][H_2O][/tex] as concentration of water will be const.
Now,
This formation of [tex][Ni(NH_3)_4]^{2+}[/tex] proceeds via several steps,
Step 1:
⇒ [tex][Ni(H_2O)_4]^{2+}+NH_3 \rightleftharpoons [Ni(H_2O)_3 (NH_3)]^{2+} + H_2O[/tex]
⇒ [tex]K_1 = \frac{[Ni(H_2O)_3 (NH_3)]^{2+}}{[Ni(H_2O)_4]^{2+} [NH_3]}[/tex]
0.28 M Ca(NO3)2
Express your answer using two significant figures.
Answer:
Mass=Moles × RFM
Mass= 0.28M× 164
Mass= 45.92 grammes
Stalactites and stalagmites form as ________ precipitates out of the water evaporating in underground caves.
Stalactites and stalagmites form as ________ precipitates out of the water evaporating in underground caves.
Group of answer choices
hydrochloric acid
sodium bicarbonate
calcium carbonate
sodium chloride
sodium hydroxide
Answer:
calcium carbonate
Explanation:
A stalactite is an icicle-looking mould that is formed by the precipitation of natural minerals as a result of water dripping from the ceiling, hanging from a cave.
A stalagmites in the other hand, grows upwards and is also a mound that is formed by the deposits of minerals gotten by the water dripping on the floor of a cave.
Therefore, stalactites and stalagmites form as calcium carbonate precipitates out of the water evaporating in underground caves.
What is the molality of a glucose solution prepared by dissolving 16.7 g of glucose, C6H12O6, in 133.6 g of water
Answer:
0.696 m
Explanation:
We'll begin by calculating the number of mole in 16.7 g of C₆H₁₂O₆. This can be obtained as follow:
Mass of C₆H₁₂O₆ = 16.7 g
Molar mass of C₆H₁₂O₆ = (6×12) + (12×1) + (6×16)
= 72 + 12 + 96
= 180 g/mol
Mole of C₆H₁₂O₆ =?
Mole = mass / molar mass
Mole of C₆H₁₂O₆ = 16.7 / 180
Mole of C₆H₁₂O₆ = 0.093 mole
Next, we shall convert 133.6 g of water to Kg. This can be obtained as follow:
1000 g = 1 Kg
Therefore,
133.6 g = 133.6 g × 1 Kg / 1000 g
133.6 g = 0.1336 Kg
Thus, 133.6 g is equivalent to 0.1336 Kg.
Finally, we shall determine the molality of the solution. This can be obtained as illustrated below:
Mole of C₆H₁₂O₆ = 0.093 mole
Mass of water = 0.1336 Kg
Molality =?
Molality = mole / mass of water (in Kg)
Molality = 0.093 / 0.1336
Molality = 0.696 m
Therefore, the molality of the solution is 0.696 m
Tick (√) the statements that are correct.
a) By eating rice alone, we can fulfil nutritional requirement of our body. ( )
b) Deficiency Diseases can be prevented by eating a balanced diet. ( )
c) Balanced diet for the body should contain a variety of food items. ( )
d) Meat alone. is sufficient to provide all nutrients to the body. ( )
b) (√)
c)(✓)
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If a 520 mg sample of technetium-99 is used for diagnostic procedure, how much of Tc-99 remains after 30.0h? Half life of Tc-99 is 6.0 hours.
how many ml of 0.032 molar kmno4 are required to react with 50.0 ml of 0.100 molar h2c2o4 in the presence of excess h2so4
Answer:
62.5 ml of 0.032 M KMnO₄ are required to react with 50.0 ml of 0.100 molar H₂C₂O₄ in the presence of excess H₂SO₄
Explanation:
The balanced reaction is:
2 KMnO₄ + 5 H₂C₂O₄ + 3 H₂SO₄ → K₂SO₄ + 2 MnSO₄ + 8 H₂O + 10 CO₂
By stoichiometry of the reaction (that is, the relationship between the amount of reagents and products in a chemical reaction), the following amounts of moles of each compound participate in the reaction:
KMnO₄: 2 moles H₂C₂O₄: 5 moles H₂SO₄: 3 moles K₂SO₄: 1 mole MnSO₄: 2 moles H₂O: 8 moles CO₂: 10 molesMolarity or Molar Concentration is the number of moles of solute that are dissolved in a certain volume.
The molarity of a solution is calculated by dividing the moles of the solute by the volume of the solution:
[tex]Molarity=\frac{number of moles of solute}{volume}[/tex]
Molarity is expressed in units [tex]\frac{moles}{liter}[/tex]
In this case, 50 mL (0.05 L) of 0.1 M H₂C₂O₄ react. So, replacing the data in the definition of molarity:
[tex]0.1 M=\frac{number of moles of solute}{0.05 L}[/tex]
Solving:
number of moles of solute= 0.1 M*0.05 L
number of moles of solute= 0.005 moles
So, 0.005 moles of H₂C₂O₄ react. Then you can apply the following rule of three: if by stoichiometry 5 moles of H₂C₂O₄ react with 2 moles of KMnO₄, 0.005 moles of H₂C₂O₄ react with how many moles of KMnO₄?
[tex]moles of KMnO_{4} =\frac{0.005moles of H_{2} C_{2} O_{4}* 2moles of KMnO_{4} }{5moles of H_{2} C_{2} O_{4} }[/tex]
moles of KMnO₄= 0.002 moles
Knowing that the molarity of KMnO₄ is 0.032 M, replacing in its definition and solving:
[tex]0.032 M=\frac{0.002 moles}{volume}[/tex]
[tex]volume=\frac{0.002 moles}{0.032 M}[/tex]
volume= 0.0625 L= 62.5 mL
62.5 ml of 0.032 M KMnO₄ are required to react with 50.0 ml of 0.100 molar H₂C₂O₄ in the presence of excess H₂SO₄
The compound chromium(II) chloride is a strong electrolyte. Write the transformation that occurs when solid chromium(II) chloride dissolves in water. Be sure to specify states such as (aq) or (s).
Answer:
CrCl₂(s) ⇒ Cr²⁺(aq) + 2 Cl⁻(aq)
Explanation:
Chromium (II) chloride is a strong electrolyte, that is, when dissolved in water, it completely dissociates into the ions. The cation is chromium (II) and the anion is chloride. The balanced equation for the solution of chromium (II) chloride is:
CrCl₂(s) ⇒ Cr²⁺(aq) + 2 Cl⁻(aq)
Kati was in the kitchen when she heard a crash. She went into her bedroom and found her window broken and a baseball lying on the ground. Kati said "this baseball broke my window." This statement is an
Answer: inference because she drew a conclusion based on evidence.
why?:
Because the evidence was that she heard the crashing sound, and then when she came into her room saw the broken window and baseball.
It was not an observation because she did not directly see the baseball going through the window
Carbonic anhydrase is strongly inhibited by the drug acetazolamide, which is used as a diuretic (i.e., to increase the production of urine) and to lower excessively high pressure in the eye (due to accumulation of intraocular fluid) in glaucoma.
a. True
b. False
Answer:
a. True
Explanation:
There is strong inhibition of Carbon Anhydrase by Aceta-zolamide Carbonic Anhydrase. The drug acetazolamide is used as diuretic which increase the urine production in human body. It lowers pressure in eye in glaucoma.
Explain the term global warming
Answer: A gradual increase in the overall temperature of the earth's atmosphere generally attributed to the greenhouse effect caused by increased levels of carbon dioxide, chlorofluorocarbons, and other pollutants.
Explanation:
Is sucrose classified as aldose or ketose?
Answer:
Because sucrose is a complex disaccharide, it is not classified as either an aldose or a ketone. Instead, it is a compound that contains both. glucose is aldose sugar and fructose is a ketose sugar.
A hydrocarbon contains only the elements____?
Explanation:
elements are carbons and hydrogen
Answer:
Carbon and Hydrogen.
Explanation:
It’s in the name Hydro (H) Carbon (C)
Calculate the concentration of ammonium nitrate in a solution prepared by dissolving 3.20 g of the salt in enough water to make 100. mL of solution, then diluting 2.00 mL of this solution to a volume of 25.00 mL.
Answer:
.032 M .
Explanation:
Molecular weight of ammonium nitrate is 80 .
3.2 g = 3.2 / 80 moles
= .04 moles
volume = 100 mL = 0.1 L
Molarity of 100 mL solution = .04 moles / 0.1 L
= 0.4 M solution.
Now 2 mL solution of 0.4 M is diluted to a volume of 25 mL .
Using the formula S₁ V₁ = S₂V₂
0.4 M x 2 mL = S₂ x 25 mL
S₂ = .4 x 2 / 25
= .032 M
Hence required concentration is .032 M .
Assuming tea leaves contain 5.0% caffeine by weight what is the maximum weight of caffeine you could isolate from 10.g of tea leaves? Show your work.
Answer:
0.50 g Caffeine
Explanation:
Step 1: Given data
Concentration of caffeine by weight in tea leaves: 5.0%
Mass of tea leaves: 10. g
Step 2: Calculate the maximum weight of caffeine that can be isolated
The concentration of caffeine by weight in tea leaves is 5.0%, that is, there are 5.0 g of caffeine per 100 g of tea leaves. The maximum weight of caffeine in 10. g of tea leaves is:
10. g Tea leaves × 5.0 g Caffeine/100 g Tea leaves = 0.50 g Caffeine
examples s name of thosse food items we can store for a month?
Answer:
1. Nuts
2. Canned meats and seafood
3. Dried grains
4. Dark chocolate
5. Protein powders
Help naming this plzzzzzzzzzzzzz
Answer:
A. 3-chloro-1-methylcyclobutane.
Explanation:
Hello there!
In this case, according to the given information, it turns out possible for us to infer that the name of this compound is A. 3-chloro-1-methylcyclobutane because of the fact that the parent chain is a cyclobutane which starts by the methyl radical as it has the priority over the chlorine radical which is actually named first at the third carbon (clockwise).
Therefore the name is given in A, accordingly to the IUPAC rules of nomenclature.
Regards!
What is the direct function of the energy released from the nuclear chain reaction in a nuclear power plant? turning the blades of the turbine heating water to produce steam powering the condenser carrying electricity from the plant to consumers
Answer:
the energy released is to make steam to create electricity. yes you are right i just didnt feel like being super technical
In a nuclear reaction, the direct function of the energy released from the nuclear chain reaction in a nuclear power plant is turning the blades of the turbine heating water to produce steam .
What are nuclear reactions?There are two types of nuclear reactions which are nuclear fusion and nuclear fission .They involve the combination and disintegration of the element's nucleus respectively.
In nuclear fission, the nucleus of the atom is bombarded with electrons of low energy which splits the nucleus in to two parts .Large amount of energy is released in the process.It is used in nuclear power reactors as it produces large amount of energy.
In nuclear fusion,on the other hand, is a reaction which occurs when two or more atoms combine to form a heavy nucleus.Large amount of energy is released in the process which is greater than that of the energy which is released in nuclear fission process.
Learn more about nuclear reactions,here:
https://brainly.com/question/12786977
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Use dimensional analysis to solve the following problems. Pay attention to correct use of units and correct use of significant figures in calculations. Please show work!
3) Convert 0.250 moles of aluminum sulfate to grams.
4) Convert 2.70 grams of ammonia to moles.
Answer:
0.000731 grams aluminium sulfate
46.0 mols ammonia
Explanation:
ALS = shorthand for aluminium sulfate which has a molar mass of 342.15 g/mol
[tex]ALS: \frac{0.250mols}{1} *\frac{1g}{342.15mols} = \frac{0.250g}{342.15}=0.0007307 g[/tex]
NH3 has a molar mass of 17.031 g/mol
[tex]NH3: \frac{2.70g}{1} *\frac{17.031mols}{1g} = \frac{0.250g}{342.15}=45.9837 mols[/tex]
Aluminium sulphate (AlS) whose molar mass is= [tex]\sf{ 342.15\dfrac{g}{mol} }[/tex]
we have to find the 0.250 moles of aluminum sulphate.
[tex]\implies AlS=\dfrac{1g}{342.15~mole}×0.250~mole \\\\\implies AlS=\dfrac{0.250}{342.15}\\\\\implies \dfrac{\frac{250}{1000}}{\frac{34215}{100}}\\\\\implies \dfrac{250}{1000}×\dfrac{100}{34215}\\\\=0.00073067\approx{0.0007307~g}[/tex]
[tex]\\\\\\[/tex]
Ammonia(NH3) whose molar mass is =[tex]\sf{17.031\dfrac{mol}{g} }[/tex]
We have to find 2.70 grams of ammonia
[tex]\implies NH_{3}=\dfrac{17.031~mol}{1g}×2.70g\\\\ 17.031×2.70\\\\\dfrac{17031}{1000}×\dfrac{270}{100}\\\\ \dfrac{4598370}{100000}\\\\=45.9837\approx{46~mole}[/tex]
A gas occupies a volume of 202 ml at a pressure of 505 torr. To what pressure must the gas be subject in order to change the volume to 65.0 ml
Answer:
1569 torr
Explanation:
Assuming ideal behaviour and constant temperature, we can solve this problem by using Boyle's law, which states:
V₁P₁ = V₂P₂Where in this case:
V₁ = 202 mLP₁ = 505 torrV₂ = 65.0 mLP₂ = ?We input the data given by the problem:
202 mL * 505 torr = 65.0 mL * P₂And solve for P₂:
P₂ = 1569 torrProteins are:
amino acids.
carbohydrates.
minerals.
sugars.
What is the molecular geometry of CIO3F as predicted by the VSEPR model?
Multiple Choice
trigonal pyramidal
square planar
square pyramidal
tetrahedral
octahedral
Explanation:
since there are no lone pairs on the central atom, the shape will be tetrahedral
what is Lewis acid and Lewis base? give examples
Explanation:
example is copper iron...........
Melanie has completed the analysis of her data for the reaction of KMnO4 with malonic acid and data for a reaction of KMnO4 with tartaric acid. She compared the activation energies, Ea, she calculated for the two reactions and found the Ea for the malonic acid reaction to be greater than the Ea for the tartaric acid reaction.
Required:
What does this mean about the magnitude of the rate constant, k, and the rate of the reaction?
Answer:
See explanation
Explanation:
The relationship between the activation energy and rate of reaction is best captured by the Arrhenius equation;
k= Ae^-Ea/RT
Where;
k= rate constant
A= pre-exponential factor
Ea=activation energy
R= gas constant
T= temperature
We can see from the foregoing that, as the activation energy increases, the rate of reaction decreases and vice versa. reactions that have a very high activation energy are markedly slow.
Since the activation energy for the malonic acid reaction is found to be greater than the activation energy for the tartaric acid reaction, then the rate of the malonic acid reaction(k) will be slower than that of the tartaric acid reaction.
The study of chemistry and bonds is called chemistry. There are two types of elements metal and nonmetals.
The correct answer is mentioned below.
What is the Arrhenius equation?The relationship between the activation energy and rate of reaction is best captured by the Arrhenius equationThe equation is as follows:-
[tex]k= Ae^{-Ea/RT[/tex] Where;
k= rate constantA= pre-exponential factorEa=activation energyR= gas constantT= temperatureWe can see from the foregoing that, as the activation energy increases, the rate of reaction decreases and vice versa. reactions that have very high activation energy are markedly slow. Since the activation energy for the malonic acid reaction is found to be greater than the activation energy for the tartaric acid reaction, then the rate of the malonic acid reaction(k) will be slower than that of the tartaric acid reaction.
Hence, the correct answer is mentioned above.
For more information about the equation, refer to the link:-
https://brainly.com/question/1388366
give one use of zinc
Plastic is a polymer
-True
-False
TRUE
Explanation:
*not sure about this answer
办理教留服学位学历认证Q/微29304199英属哥伦比亚UBC毕业证文凭学位证书offer操办英属哥伦比亚留信认证成绩单
Answer:
please translate in english
A ligand is a molecule or ion that acts as a
Answer:
Lewis base/electron pair donors
Explanation:
Ligands are ions or neutral molecules which bond together with a central ion. They act as election pair donors, also known as Lewis bases, while the central ion they are connected to acts as the acceptor.
Therefore, a ligand is a molecule or ion that acts as a Lewis base/electron pair donors
Leaming Task 1:
Distinguish the process as spontaneous or non-spontaneous process. Write S it spontaneous and NSi non-spontaneous
on the bionk.
1. Melling ofice
2 Ruisting of ton
3. Marble going down the spiral.
4. Going up the
& Keeping the food fresh from spolage
Solution :
Spontaneous Process
A spontaneous process is defined as the process that occurs without the help of any external aid or inputs. A spontaneous process is a natural process which occurs naturally in the environment.
Non Spontaneous process
A non spontaneous process is a process which does not occur naturally. Some inputs are provided for the process to occur. Energy from external source is applied into the process to start the process.
The following processes are :
1. Melling of ice ---- Spontaneous
2 Rusting of iron --- Spontaneous
3. Marble going down the spiral. --- spontaneous
4. Going up the hill ---- Non spontaneous
5. Keeping the food fresh from spoilage --- Non spontaneous
