Answer:
301.8 g
Explanation:
We prepare a solution with 200.4 g of water (solvent) and 101.42 g of salt (solute). The mass of the solution is equal to the sum of the mass of the solvent and the mass of the solute.
m(solution) = m(solute) + m(solvent)
m(solution) = 200.4 g + 101.42 g
m(solution) = 301.8 g (we round-off to one decimal according to the significant figures rules)
An organic chemistry student was studying the solubility of Methyl-N-acetyl-α-D-glucosaminide (1-O-methyl-GlcNAc), a derivative of glucosamine, in water but inadvertently added 1 equiv. of periodic acid instead. Based on your understanding of the reactions of monosaccharides with periodates, draw the organic product that the student obtained.
Complete Question
The diagram for this question is shown on the second uploaded image
Answer:
The organic product obtained is shown on the first uploaded image
Explanation:
The process that lead to this product formation is known as oxidative cleavage which is a reaction that involves the cleavage of a carbon to carbon bond at the same time this carbon which formed the carbon bond are oxidized i.e oxygen is been added to them
A blood sample is left on a phlebotomy tray for 4 hours before it is delivered to the laboratory. Which group of tests could be performed:
An attempt at synthesizing a certain optically active compound resulted in a mixture of its enantiomers. The mixture had an observed specific rotation of 14.1°. If it is known that the specific rotation of the R enantiomer is –28.4°, determine the percentage of each isomer in the mixture. g
Answer:
The percentage of the R-enantiomer is 26.18% while the percentage of the S-enantiomer is 73.82%
Explanation:
If the specific rotation of R enantiomer = -28.4, then the specific rotation of S = +28.4
Now, let us have x = % R, thus
% S = 100-x =y
Hence;
{- 28.4x + 28.4( 100 -x)}/100= 14.1
Thus;
-28.4x + 2840 -28.4x = 1410
-56.8x + 2840 = 1410
-56.8x = 1410-2840
-56.8x = -1430
x = 1430/56.8
x = 26.18%
y = 100-26.18% = 73.82%
After recrystallizing an impure sample with isopropanol, you isolate your product by filtration. What solvent do you use to wash your crystals? Room temperature distilled water Room temperature isopropanol Ice cold distilled water Ice cold isopropanol
Answer:
The correct answer is ice cold isopropanol.
Explanation:
Any compound in the initial stage is first dissolved in any suitable solvent and is heated for a certain duration for the process of recrystallization. Afterward, the compound is kept at room temperature so that it gets cooled gradually. In the process, the impurities remain dissolved in the solvent and the pure compound gets separated in the form of a precipitate.
Post all this, the filtration of the pure compound is done and is then washed with the cold solvent, which was initially used to dissolve the compound. Therefore, the appropriate solvent to use in the process is ice-cold isopropanol.
What is the name of this molecule? (will give BRAINLIEST)
A straight chain of four carbons. There is a triple bond between the second and third carbons when counting from left to right or right to left.
Answer:
2 - Butyne
Explanation:
The name of the molecule with a carbon atoms arranged in a straight chain with a triple bond between the second and third carbons is 2 - Butyne.
2- Butyne is an alkyne with structural formula given below. Some of the properties of Butyne include it is a produced artificially, it is volatile and colorless in nature.
Hence, the given molecules described is 2 - Butyne.
An EpiPen, used to treat anaphalactic allergic reactions, contains 0.30 mg of epinephrine. The concentration of epinephrine in each syringe is 1.0 mg/mL. What is the volume, in milliliters (mL), of solution in each syringe
Answer:
0.3mL
Explanation:
Mass = 0.30mg
Concentration = 1.0 mg/mL
Volume = x
The relationship between the three parameters is given as;
Concentration = Mass / Volume
Making Volume our subject of interest we have;
Volume = Mass / Concentration
Substituting the values we have;
Volume = 0.30 mg / 1 mg/mL = 0.3mL
Which of the following structures in the human body has the highest level of organization
Answer:
The brain
Explanation:
With all those instructions the body recqures to respond to it must be so
Hope it helps
Wax melts when it is heated which most likely describes what is true of the result of this reaction
Answer:
Was is a hydrocarbon therefore when heated some co2 escapes but later solidifies
Explanation:
Hope it helps
In this reaction: Mg (s) + I₂ (s) → MgI₂ (s)
If 2.34 moles of Mg react with 3.56 moles of I₂, and 1.76 moles of MgI₂ form, what is the percent yield?
Answer:
98.9%
Explanation:
2 moles of I₂ are required for each mole of Mg, so the reaction is limited by the available I₂. The 3.56 moles of I₂ should react with 1.78 moles of Mg to produce 1.78 moles of MgI₂. Instead, we get 1.76 moles of MgI₂.
The yield is 1.76/1.78 × 100% ≈ 98.876%
The yield is 98.9% of the quantity expected based on available reactants.
Catalysts are substances that increase the rate of reaction but can be recovered unchanged at the end of the reaction. Catalysts can be classified as either homogeneous (same state as reactants) or heterogeneous (different state than reactants).
Platinum is used to catalyze the hydrogenation of ethylene:
H2(g)+CH2CH2(g)−⟶Pt(s)CH3CH3(g)
Chlorofluorocarbons (CFCs) catalyze the conversion of ozone (O3) to oxygen gas (O2):
2O3(g)−⟶CFC(g)3O2(g)
Magnesium catalyzes the disproportionation of hydrogen peroxide to produce water and oxygen:
2H2O2(aq)−⟶Mg(s)2H2O(l)+O2(g)
What type of catalysts are platinum, CFCs, and magnesium under these conditions?
Answer:
- Platinum acts as a heterogeneous catalyst in the hydrogenation of ethylene.
- CFCs act as homogeneous catalysts in the conversion of ozone to oxygen gas.
- Magnesium acts as a heterogeneous catalyst in the disproportionantion of hydrogen peroxide.
Explanation:
Hello,
For the given reactions, considering the definition of homogeneous and heterogeneous catalyst, we can identify that is each catalyst behave as follows:
- Platinum acts as a heterogeneous catalyst in the hydrogenation of ethylene as all the reactants are gaseous but it remains solid.
- CFCs act as homogeneous catalysts in the conversion of ozone to oxygen gas as it remains gaseous as well as both ozone and oxygen.
- Magnesium acts as a heterogeneous catalyst in the disproportionantion of hydrogen peroxide as it is solid whereas the other species are aqueous, liquid and gaseous
Best regards.
3. Are all amino acids are chiral? Why or why not? Protein only contain ____ (L-/D-) amino acids. Which organic molecule is the standard molecule for L-/D- configuration system? The chiral carbon in L-Alanine is ______ (R- /S-) configuration, but in D-Alanine is ________ (R-/S-) configuration.
Answer:
Protein are essential in body cells for the repair of worn out tissues. Amino acid is gotten when protein is broken down under certain conditions.
All amino acids are chiral with the exception of glycine. This means they have a central carbon atom with the R-, -COOH, and -NH2 group attached to it.
Protein contain only L amino acid because the L amino acid is the only type used by cells.
The chiral carbon in L-Alanine is S-configuration and D-Alanine is R-configuration.
where are chemicals found in the home?
a. only in the bathroom
b. only in locked cabinets
c. in every room
d. only in the kitchen
Answer:
c
Explanation:
chemicals can be found in every part of our lives
what are mineralocorticoids
Explanation:
it is used to describe those action of adrenal corticosteroids that produce sodium
A 950.0 mL solution of potassium permanganate was made by dissolving 45.0 g KMnO4 in 750.0 mL of water. Assume water has a density of 1.00 g/mL. (Molar Mass for H = 1 , O = 16 , K= 39 , Mn= 55 ) The mole fraction of the solute =
Answer:
The correct answer is 6.67×10⁻³.
Explanation:
Based on the given question, the amount of solute (KmNO4) is 45 grams. The molecular weight of KmNO4 is 158 gram per mole. The moles of solute can be determined by using the formula,
n = mass/molecular weight
n = 45/158 = 0.28
The amount of solvent (water) given is 750 milliliters, and the density of water is 1 gm. per ml, 18 gram per mole is the molecular weight of water. So, the moles of solvent will be,
n = 750/18 = 41.7
The formula for calculating mole fraction is,
Mole fraction = mole of solute / (mass of solute + mole of solvent)
The mole fraction of solute can be determined by putting the values in the above mentioned formula,
Mole fraction of KmNO4 = 0.28/(0.28+41.7)
= 0.28/41.98
= 6.67 × 10⁻³ or 7 × 10⁻³.
dropping an Alka-Seltzer tablet into a glass of water _________________________________________ b. bleaching a stain _________________________________________ c. burning a match _________________________________________ d. rusting of an iron nail
Answer:
Hi there!
When dropping Alka-Seltzer into a glass of water, bubbles immediately appear and the solid substance “disappears”, dissolves, into the water. This forms a new compound, a liquid, which means a reaction took place.
Unscramble the following words to form a complete
sentence about the cycles of nature:
limited is through environment Matter recycled the on Earth is and
Answer:
recycled is limited through enviroment and matter on earth
Explanation:
Dry chemical hand warmers utilize the oxidation of iron to form iron oxide according to the following reaction: 4Fe(s)+3O2(g)→2Fe2O3(s) Standard thermodynamic quantities for selected substances at 25 ∘C Reactant or product ΔH∘f(kJ/mol) Fe(s) 0.0 O2(g) 0.0 Fe2O3(s) −824.2 Calculate ΔH∘rxn for this reaction.
Answer:
-1648.4 kJ/mol
Explanation:
Based on Hess's law:
ΔHr = ∑n×ΔH°f(products) - ∑n×ΔH°f(reactants)
In the reaction:
4Fe(s) + 3O₂(g) → 2Fe₂O₃(s)
ΔHr = 2 ΔH°f {Fe₂O₃} - (4ΔH°f {Fe(s)} + 3ΔH°f{O₂(g)}
As:
ΔH°f {Fe₂O₃} = -824.2kJ/mol
ΔH°f {Fe(s)} = 0.0kJ/mol
ΔH°f{O₂(g)} = 0.0kJ/mol.
Thus,
ΔHr = 2 ₓ -824.2kJ/mol =
-1648.4 kJ/molAnswer:
-1648.4 kJ
Explanation:
The product has the only nonzero heat of formation, so it is the only value needed to calculate the enthalpy of this reaction. Normally, you would want to express the enthalpy of a reaction with respect to one mole of a chemical species, whether it is a reactant or product. However, since the balanced chemical equation contains only coefficients greater than 1, you should consider how the enthalpy relates to one mole of each substance according to the coefficients. In other words, − 1648.4 kJ of heat is released when 4 mol of Fe reacts with 3 mol of O2 to produce 2 mol of Fe2O3 .
A 20.0-mL sample of lake water was acidified with nitric acid and treated with excess KSCN to form a red complex (KSCN itself is colorless). The solution was then diluted to 50.0-mL and put in a 1.00 cm pathlength cell, where it yielded an absorbance of 0.345. For comparison, a 5.0-mL reference sample of 4.80 x 10-4 M Fe3 was treated with HNO3 and KSCN and diluted to 50.0 mL. The reference solution was also placed in a 1.00-cm cell and gave an absorbance of 0.512. What is the concentration of Fe3 in Jordan Lake
Answer:
8.09x10⁻⁵M of Fe³⁺
Explanation:
Using Lambert-Beer law, the absorbance of a sample is proportional to its concentration.
In the problem, the Fe³⁺ is reacting with KSCN to produce Fe(SCN)₃ -The red complex-
The concentration of Fe³⁺ in the reference sample is:
4.80x10⁻⁴M Fe³⁺ × (5.0mL / 50.0mL) = 4.80x10⁻⁵M Fe³⁺
Because reference sample was diluted from 5.0mL to 50.0mL.
That means a solution of 4.80x10⁻⁵M Fe³⁺ gives an absorbance of 0.512
Now, as the sample of the lake gives an absorbance of 0.345, its concentration is:
0.345 × (4.80x10⁻⁵M Fe³⁺ / 0.512) = 3.23x10⁻⁵M.
As the solution was diluted from 20.0mL to 50.0mL, the concentration of Fe³⁺ in Jordan lake is:
3.23x10⁻⁵M Fe³⁺ × (50.0mL / 20.0mL) = 8.09x10⁻⁵M of Fe³⁺
The concentration of Fe³⁺ in Jordan Lake is = 8.09* 10⁻⁵ M
According to Lambert-Beer law ;The rate of absorbance of a sample is directly proportional to concentration of the sample
The reaction that produces a red complex
Fe³⁺ + KScN ----> Fe ( SCN )₃ ( red complex )
First step: Determine the Concentration of Fe³⁺ in reference sample
= 4.80x10⁻⁴ * ( 5.0 / 50.0 ) = 4.80 * 10⁻⁵M
reference sample was diluted from 5.0 mL to 50.0 mL
∴ Concentration of 4.80 * 10⁻⁵M has an absorbance = 0.512
Given that Lake sample absorbance = 0.345
Next step : Determine the concentration of the lake sample
Concentration of lake sample :
= absorbance of lake sample * ( conc of reference sample / absorbance )
= 0.345 * ( 4.80* 10⁻⁵ / 0.512 ) = 3.23* 10⁻⁵M.
Final step : Determine the concentration of Fe³⁺ in Jordan lake
= 3.23 * 10⁻⁵ * ( 50.0mL / 20.0mL) = 8.09* 10⁻⁵ M
Note : Solution was diluted from 20.0 mL to 50.0 mL
Hence we can conclude that The concentration of Fe³⁺ in Jordan Lake is = 8.09* 10⁻⁵ M .
Learn more : https://brainly.com/question/24287054
In E. coli, the enzyme hexokinase catalyzes the reaction: Glucose + ATP → glucose 6-phosphate + ADP The equilibrium constant, Keq, is 7.8 x 102. In the living E. coli cells, [ATP] = 7.9 mM; [ADP] = 1.04 mM, [glucose] = 2 mM, [glucose 6-phosphate] = 1 mM. Determine if the reaction is at equilibrium. If the reaction is not at equilibrium, determine which side the reaction favors in living E. coli cells.
Answer:
Explanation:
Glucose + ATP → glucose 6-phosphate + ADP The equilibrium constant, Keq, is 7.8 x 102.
In the living E. coli cells,
[ATP] = 7.9 mM;
[ADP] = 1.04 mM,
[glucose] = 2 mM,
[glucose 6-phosphate] = 1 mM.
Determine if the reaction is at equilibrium. If the reaction is not at equilibrium, determine which side the reaction favors in living E. coli cells.
The reaction is given as
Glucose + ATP → glucose 6-phosphate + ADP
Now reaction quotient for given equation above is
[tex]q=\frac{[\text {glucose 6-phosphate}][ADP]}{[Glucose][ATP]}[/tex]
[tex]q=\frac{(1mm)\times (1.04 mm)}{(7.9mm)\times (2mm)} \\\\=6.582\times 10^{-2}[/tex]
so,
[tex]q<<K_e_q[/tex] ⇒ following this criteria the reaction will go towards the right direction ( that is forward reaction is favorable until q = Keq
Select the correct answer.
What effect does an increase in products have on the reaction rate of a mixture at equilibrium?
A.
The forward reaction rate increases.
B.
Both the forward and the reverse reaction rates decrease.
Both the forward and the reverse reaction rates increase.
D.
The reverse reaction rate increases.
Reset
Next
Answer:
At equilibrium the rate of the forward reaction is equal to the rate of the backward reaction.
When the product of a reaction at equilibrium is increased the equilibrium will shift left or to the reactant side. As a result the excess product will get converted to reactant. This is in accordance to Le Chatelier's principle.
Le Chatelier's principle states that when a system is subjected to stress the equilibrium will shift in a direction to minimize effect of the stress.
Thus the products added to the system at equilibrium will make the equilibrium shift to the reactant side, the rate of the reverse or backward reaction will increase.
Explanation:
Hope This Helps Amigo!
A 1.44 L buffer solution consists of 0.137 M butanoic acid and 0.275 M sodium butanoate. Calculate the pH of the solution following the addition of 0.069 moles of NaOH . Assume that any contribution of the NaOH to the volume of the solution is negligible. The Ka of butanoic acid is 1.52×10−5 .
Answer:
The answer is "[tex]P^{H}=5.379[/tex]".
Explanation:
[tex]\ NaOH \ value = \frac{n}{v}\\\\[/tex]
[tex]=\frac{0.069\ moles}{0.144L}\\\\=0.04791\ M[/tex]
[tex]\ Ka=1.52 \times 10^{-5}\\\\P^{ka} = -10g \ ka \\\\[/tex]
[tex]= -10 \times 1.52 \times 10^{-5}\\\\= 4.82\\[/tex]
Equation:
[tex]CH_3CH_2CH2COOH+NaOH\rightarrow CH_3CH_2CH_2COONa +H_2O\\\\[/tex]
[tex]\boxed{\left\begin{array}{ccccc}I &0.137 &0.04791 &0.275 & -- \\ C &-0.04791 &-0.04791 &+0.04791 & -- \\E &0.08909 &0&0.32291 & -- \end{array}\right}[/tex]
[tex]P^{H}= P^{ka}+\log\frac{CH_3CH_2CH_2COONa}{CH_3CH_2CH_2COOH}\\\\[/tex]
[tex]= 4.82+\log\frac{0.32291}{0.08909}\\\\=5.379[/tex]
Question 5 of 20:
Select the best answer for the question.
5. Which of the following is a homonuclear diatomic molecule?
O A. NH3
O B. 2002
O C. Hz
O D. CO
Answer:
Homo nuclear molecule mean having atoms of only one element,
I cant see clearly the option B and C can you correct them , 2002? Hz?
Explanation:
Answer:
H2
Explanation:
Identify the state(s) of matter that each property describes.
Answer:solid,liquid,gas,plasma
Explanation:
This question seems incomplete. I believe the full question is as followed:
Identify the state(s) of matter that each property describes.
1.) takes the shape of its container:
O gas
O liquid
O solid
2.) fills all available space:
O gas
O liquid
O solid
3.) maintains its shape:
O gas
O liquid
O solid
4.) can be poured:
O gas
O liquid
O solid
5.) is compressible:
O gas
O liquid
O solid
6.) has a fixed volume:
O gas
O liquid
O solid
The answers to the 1st are gas and liquid.
The answer to the 2nd is gas.
The answer to the 3rd is solid.
The answer to the 4th is liquid.
The answer to the 5th is gas.
The answers to the 6th are liquid and solid.
4-Nitrophenol, NO2C6H4OH (pKa 7.15), is only slightly soluble in water, but its sodium salt, NO2C6H4O-Na+, is quite soluble in water. Describe the solubility of 4-nitrophenol in solutions of sodium hydroxide, sodium bicarbonate (NaHCO3), and sodium carbonate (Na2CO3). The pKa values for the conjugate acids of sodium hydroxide, sodium bicarbonate (NaHCO3), and sodium carbonate (Na2CO3) are 15.7, 6.36, and 10.33, respectively. Aqueous NaOH: _________ Aqueous NaHCO3: _________ Aqueous Na2CO3: _________
Answer:
Aqueous NaOH: soluble
Aqueous NaHCO₃: insoluble
Aqueous Na₂CO₃: soluble
Explanation:
The organic acid is insoluble. Its salt (ionic) is soluble.
The important principle is:
If you have two acids in a flask, the stronger acid (smaller pKₐ) will protonate the weaker one. The stronger acid will become ionic and therefore more soluble.
1. In NaOH
Let's write the formula for 4-nitrobenzoic acid as HA.
The equation for the reaction is
HA + OH⁻ ⇌ A⁻ + H₂O
pKₐ: 7.15 15.7
HA is the stronger acid. It will protonate the hydroxide ion and be converted to the soluble 4-nitrobenzoate ion.
4-Nitrophenol is soluble in NaOH.
2. In NaHCO₃
HA + HCO₃⁻ ⇌ A⁻ + H₂CO₃
pKₐ: 7.15 6.36
HCO₃⁻ is the stronger acid. It will protonate 4-nitrophenol.
4-Nitrobenzoic acid is insoluble in NaHCO₃.
3. In Na₂CO₃
HA + CO₃²⁻ ⇌ A⁻ + H₂CO₃
pKₐ: 7.15 10.33
HA is the stronger acid. It will protonate the carbonate ion.
4-Nitrophenol is soluble in Na₂CO₃.
The molar enthalpy of
mole of a liquid.
is the heat required to vaporize one
thermochemical equation
combustion
released
vaporization
fusion
absorbed
heat
Answer:
vaporization
Explanation:
The molar enthapy of _vaporization______ is the heat required to vaporize one mole of a liquid”
What is Hess‘s law please help
The correct answer is D. Hess's law states than the enthalpy of a reaction does not depend on the reaction path
Explanation:
In a chemical reaction, the enthalpy refers to the internal energy in a system and how this increases or decreases during the reaction. According to Hess's law proposed by German Hess in 1940, the enthalpy does not depend on the reaction path or the number of steps in a reaction. This means one reaction of only one step will have the same enthalpy that if the reaction occurs in several steps because the energy that requires all the process is the same. Thus, the "Hess's law states than the enthalpy of a reaction doe s not depend on the reaction path".
What is the balanced form of the chemical equation shown below?
Na2SO4(aq) + Sr(NO3)2(aq) → SrSO4(s) + NaNO3(aq)
A. Na2SO4(aq) + Sr(NO3)2(aq)
SISO4(s) + NaNO3(aq)
B. NaSO4(aq) + SINO3(aq) → SSO4(s) + NaNO3(aq)
C. Na2SO4(aq) → SrSO4(s) + 2NaNO3(aq)
Ο Ο
D. Na2SO4(aq) + 2Sr(NO3)2(aq) → 2SSO4(s) + 2NaNO3(aq)
Answer:
C. Na₂SO₄(aq) + Sr(NO₃)₂(aq) → SrSO₄(s) + 2 NaNO₃(aq)
Explanation:
Based on the equation:
Na₂SO₄(aq) + Sr(NO₃)₂(aq) → SrSO₄(s) + NaNO₃(aq)
As you can see, sulfate ions (SO₄) are been replaced for nitrate ions (NO₃). That is a double replacement reaction and is a very important information because 2 NO₃ ions in Sr(NO₃)₂ are producing 1 NO₃ ion. To balance NO₃:
Na₂SO₄(aq) + Sr(NO₃)₂(aq) → SrSO₄(s) + 2 NaNO₃(aq)
1 SO₄ ion in Na₂SO₄ produce 1 SO₄ ion in SrSO₄. And Na and Sr metals are balanced yet. Thus, the balanced form of this chemical equation is:
Na₂SO₄(aq) + Sr(NO₃)₂(aq) → SrSO₄(s) + 2 NaNO₃(aq)At high temperatures one mole of hydrogen gas reacts with one mole of bromine gas to form hydrogen bromide. At a given temperature the equilibrium constant is 57.6. If at the same temperature, a mixture of 4.67 × 10^-3M bromine gas, 2.14 × 10^−3 hydrogen gas, and 2.40 × 10^−2M hydrogen bromide gas is made, then:
a. the system is at equilibrium.
b. the system is far from equilibrium and will shift to form more hydrogen gas.
c. the system is far from equilibrium and will shift to form more hydrogen bromide gas.
d. nothing can be deduced since we do not know whether the reaction is endothermic or exothermic.
e. nothing can be deduced since we do not know whether the equilibrium constant is Kc or Kp.
Answer:
a. the system is at equilibrium.
Explanation:
Hello,
In this case, the undergoing chemical reaction is:
[tex]H_2+Br_2\rightleftharpoons 2HBr[/tex]
Thus, the law of mass action is given by:
[tex]Keq=\frac{[HBr]^2}{[H_2][Br_2]} =57.6[/tex]
Nonetheless, for the given point of 4.67 × 10^-3M bromine gas, 2.14 × 10^−3 hydrogen gas, and 2.40 × 10^−2M hydrogen bromide gas we should compute the reaction quotient in order to know whether the direction of the reaction is to left or to right, thus:
[tex]Q=\frac{[HBr]^2}{[H_2][Br_2]} =\frac{(2.40x10^{-2})^2}{(4.67x10^{-3})(2.14x10^{-3})} \\\\Q=57.6[/tex]
Therefore, since Keq=Q, we say that the system is at equilibrium, for that reason, the answer is a.
Best regards.
10. How many grams of NH, are present in 6 moles
of NH,?
Answer:
90.08784 grams
Explanation:
idk
ch3-ch2-ch-ch(cl)-ch=o IUPAC name
Answer:
2-chloropentanal
Answer:
2-chloropentanal
Explanation:
ch3-ch2-ch-ch(cl)-ch=o IUPAC name
H H H H
H - C - C - C - C - C = O
H H H Cl
So as can be seen 2 as the Chlorine is on the second carbon.
Chloro because of the chlorine.
Pent because there's 5 carbon
al because there's an aldehydes
Aldehyde = −CHO
2-chloropentanal