Answer:
9.82 km.
Explanation:
Hello,
In this case, given the conversion factors from miles to kilometres and from miles to feet, we can directly compute the jet’s cruising altitude in kilometres as shown below:
[tex]32,200ft\times \frac{1mile}{5280ft}\times \frac{1.61km}{1mile} \\\\=9.82km[/tex]
Best regards.
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 .
How is the mass of the atom calculated?
by adding the number of protons and electrons
by adding the number of protons and neutrons
by subtracting the number of electrons from the number of protons
by adding the number of neutrons and electrons
The mass of the atom is calculated by adding the number of protons and neutrons .
What do you mean by atomic mass of an element ?The total mass of one atom of an element is defined as its atomic mass. The atomic mass is taken as the mass of protons and neutrons in an atom.
1 a m u = 1.66 ×10⁻²⁴g
To calculate the atomic mass of an element -:
The atomic mass of the single atom can be calculated by adding the total number of protons and the total number of neutrons of that particular atom.
Atomic mass Number = Number of protons + number of neutrons
Hence ,in this way the atomic mass is calculated of an atom .
Learn more about atomic mass ,here:
https://brainly.com/question/17067547
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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.
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]
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.
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
Suppose you were preparing 1.0 L of a bleaching solution in a volumetric flask, and it calls for 0.21 mol of NaOCl. If all you had available was a jug of bleach that contained 0.78 M NaOCl, what volume of bleach would you need to add to the volumetric flask before you added enough water to reach the 1.0 L line
Answer: brainliesss plssssssss
0.256 L
Explanation:
We should use the following formula:
concentration (1) × volume (1) = concentration (2) × volume (2)
concentration (1) = 0.82 M NaOCl
volume (1) = ?
concentration (2) = 0.21 M NaOCl
volume (2) = 1 L
volume (1) = [concentration (2) × volume (2)] / concentration (1)
volume (1) = [0.21 / 1] / 0.82 = 0.256 L
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”
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%
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.
A structural model of retinol is shown below. How many hydrogen atoms are
in retinol?
HC CHS
H3C
H3c
"OH
CH
A. 30
B. 23
C. 16
D. 26
Answer:
A. 30
Explanation:
Retinol is the chemical form of Vitamin A. It has a chemical formula of C20H30O.
It is processed when retinyl palmitate is broken down in the small intestine. Retinol helps in the proper regulation of eye cells hence a vital component in ensuring good eye sight.
It also helps in the neutralization of free radicals in the body and acts as an antioxidant which prevents cells of the body from ageing.
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
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
What happens at this point
Answer:
What are you referring to exactly
Explanation:
Answer: C
Explanation:
There is a difference in air pressure. That's what I put and I got a 92.
4 molecules of glucose has how many carbon hydrogen and oxygen
Answer:
24 carbons
48 hydrogens
24 oxygen
Explanation:
Classify an element having the following ground state electron configuration as an alkali metal, alkaline earth metal, nonmetal, halogen, transition metal, or noble gas.
a. [Ne]3s1
b. [Ne]3s23p3
c. [Ar]4s23d104p5
d. [Kr]5s24d1
e. [Kr]5s24d105p6
Explanation:
Alkali metal refers to group1 elements.
Alkali earth metal refers to group 2 elements.
Non metals refers to elements in grouos 4 to group 7.
Halogen refers to group 17 elements
Transition Metal refers to group 3 to group 12 elements
Noble gases refer to elements in group 18.
To obtain the group number from the electronic configuration, we calculate the total number of electrons in the principal quantum number (coefficient of the letters).
a. [Ne]3s1
Principal quantum number = 3
Number of electrons present = 1
This element belongs to group 1. It is an Alkali Metal.
b. [Ne]3s23p3
Principal quantum number = 3
Number of electrons present = 2 + 3 = 5
This element belongs to group 15 (5A). It is a Non metal
c. [Ar]4s23d104p5
Principal quantum number = 4
Number of electrons present = 2 + 5 = 7
This element belongs to group 17 (7A). It is an Halogen.
d. [Kr]5s24d1
This configuration belongs to the element yttrium and has an incomplete d shell. Hence it is a transition metal.
e. [Kr]5s24d105p6
Principal quantum number = 5
Number of electrons present = 2 + 6 = 8
This element belongs to group 18 (8A). It is a Noble gas.
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.
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!
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
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.
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
rinking water suggest an upper limit of 250 mg/L for chloride ion. If 1.03×104 liters of water in a storage tank contains 1.40 grams of Cl-, what is the contaminant level in ppm? in ppb? Is this level acceptable based on EPA guidelines?
Answer:
This water has a level acceptable, 0.1359ppm and 135.9ppb.
Explanation:
1.40g of Cl⁻ are:
1.40g Cl⁻ × (1000mg / 1g) = 1400mg Cl⁻
In 1.03x10⁴L:
1400mg / 1.03x10⁴L = 0.1359mg/L.
As the upper limit of Cl⁻ in water is 250mg/L, this water has a level acceptable
ppm are the ratio between mg of solute and liters of solution, that means the tank contains 0.1359mg/L = 0.1359ppm
ppb, parts per billion are 1000 times ppm, thus, parts per billion of the storage tank are:
0.1359ppm × 1000 = 135.9ppb
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 happens in a neutralization reaction?
a
The hydrogen (H+) ions from the base and the hydroxide (OH-) ions from the acld come together to form water.
The hydrogen (H+) ions from the acid and the hydroxide (OH) ions from the base come together to form water.
A substance's pH is increased to a value greater than 7.
A solution of a known concentration and volume is added until the reaction is completed.
Answer:
Answer is letter B
Explanation:
The first one is wrong because acids release H+, not bases.
The third one is wrong because the pH is exactly 7, not greater.
The last one is wrong because it is vague and does not fit a neutralization reaction.
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.
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.
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.
what are mineralocorticoids
Explanation:
it is used to describe those action of adrenal corticosteroids that produce sodium
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.