Answer:
2
Explanation:
You write your answer with the same number of significant figures as the number with the smallest amount of figures, in this case, that number is 2.1 so your answer should be written with 2 significant figures.
A buffer solution contains 0.475 M nitrous acid and 0.302 M sodium nitrite . If 0.0224 moles of potassium hydroxide are added to 150 mL of this buffer, what is the pH of the resulting solution
Answer: The pH of the resulting solution will be 3.001
Explanation:
Molarity is calculated by using the equation:
[tex]\text{Molarity}=\frac{\text{Moles}}{\text{Volume}}[/tex] ......(1)
We are given:
Moles of NaOH = 0.0224 moles
Molarity of nitrous acid = 0.475 M
Molarity of sodium nitrite = 0.302 M
Volume of solution = 150 mL = 0.150 L (Conversion factor: 1 L = 1000 mL)
Putting values in equation 1, we get:
[tex]\text{Moles of nitrous acid}=(0.475mol/L\times 0.150L)=0.07125mol[/tex]
[tex]\text{Moles of sodium nitrite}=(0.302mol/L\times 0.150L)=0.0453mol[/tex]
The chemical equation for the reaction of nitrous acid and NaOH follows:
[tex]HNO_2+NaOH\rightleftharpoons NaNO_2+H_2O[/tex]
I: 0.07125 0.0224 0.0453
C: -0.0224 -0.0224 +0.0224
E: 0.04885 - 0.0677
The power of the acid dissociation constant is the negative logarithm of the acid dissociation constant. The equation used is:
[tex]pK_a=-\log K_a[/tex] ......(2)
We know:
[tex]K_a[/tex] for nitrous acid = [tex]7.2\times 10^{-4}[/tex]
Using equation 2:
[tex]pK_a=-\log (7.2\times 10^{-4})=3.143[/tex]
To calculate the pH of the acidic buffer, the equation for Henderson-Hasselbalch is used:
[tex]pH=pK_a+ \log \frac{\text{[conjugate base]}}{\text{[acid]}}[/tex] .......(3)
Given values:
[tex][NaNO_2]=\frac{0.0677}{0.150}[/tex]
[tex][HNO_2]=\frac{0.04885}{0.150}[/tex]
[tex]pK_a=3.143[/tex]
Putting values in equation 3. we get:
[tex]pH=3.143-\log \frac{(0.0677/0.150)}{(0.04885/0.150)}\\\\pH=3.143-0.142\\\\pH=3.001[/tex]
Hence, the pH of the resulting solution will be 3.001
write the formula two atom of iron and three atoms of oxygen
Answer:
Fe2O3 is the formula this is your correct answer
An atom has the electron configuration of 1s22s22p5 how many electrons are in that atom
Answer:
There are [tex]9[/tex] electrons in this atom.
Explanation:
Electron configuration of this atom: [tex]1s^2\, 2s^2\, 2p^5[/tex].
The electron orbitals of an atom are denoted as [tex]1s[/tex], [tex]2s[/tex], [tex]2p[/tex], [tex]3s[/tex], [tex]3p[/tex], etc. At any given time, an electron in this atom is located in exactly one orbital.
The electron configuration of an atom gives the number of electrons in each orbitals of this atom.
For example, in this atom, the superscript "[tex]2[/tex]" on the right of "[tex]1s[/tex]" means that there are two electrons in the [tex]1s\![/tex] orbital of this atom. Hence, [tex]1s^2\, 2s^2\, 2p^5[/tex] would translate to:
The [tex]1s[/tex] orbital of this atom contains [tex]2[/tex] electrons.The [tex]2s[/tex] orbital of this atom contains [tex]2[/tex] electrons.The [tex]2p[/tex] orbitals of this atom contain [tex]5[/tex] electrons.Hence, there would be [tex]2 + 2 + 5 = 9[/tex] electrons in total in this atom.
Discuss the any two applications of Beer’s law with suitable justification.
Answer: It's used in chemistry to measure the concentration of chemical solutions.
Explanation:
Beer's Law is used in chemistry to measure the concentration of chemical solutions, to analyze oxidation, and to measure polymer degradation.
The law also describes the attenuation of radiation through the Earth's atmosphere
Hydrogen bonds within liquid water are attractions between protons and hydroxide ions. are dipole-dipole attractions. are ion-induced dipole attractions. are attractions between protons and oxygen nuclei. are attractions between two hydrogen atoms.
Answer:
true because the bonds cannot be broken down
Compound A has the formula C8H8. It reacts rapidly with acidic KMnO4 but reacts with only 1 equivalent of H2 over a palladium catalyst. On hydrogenation under conditions that reduce aromatic rings, A reacts with 4 equivalents of H2, and hydrocarbon B, C8H16, is produced. The reaction of A with KMnO4 gives CO2 and a carboxylic acid C, C7H6O2.
Required:
Draw the structure of compound B below.
Answer:
C8H16 (Ethylcyclohexane).
Explanation:
From the given information:
Compound A is an alkene because it interacts with 1 unit of hydrogen across a palladium catalyst.
Also, we are given another hint that:
Compound A needs 4 equivalence of H2 to hydrogenate under circumstances that decrease aromatic rings, indicating that it is a phenyl substituted alkene.
Compound A with formula C8H8 reacts instantly with KMnO4 to produce CO2, as well as carboxylic acid, points out that Compound acts as a terminal alkene.
Therefore, we can opine that compound A is a terminal phenyl substituted alkene whose formula = C8H8 (Styrene)
The diagrammatic expression of the compound can be seen below.
However, in the presence of the palladium catalyst, the reduction of Compound A with 4 units of hydrogen produces Compound B: C8H16 (Ethylcyclohexane).
Calculate the amount of energy produced by the conversion of 50.0 kg of mass into energy. Use 3.00 x 108 m/s for the speed of light. Round to 3 significant digits.
Which setup will solve this problem?
Answer:
tanong mo sa teacher mo ok
Answer:
E = (50.0 kg)(3.00 x 108 m/s)2
Explanation:
You have selected your two primers and added all of the PCR components to a test tube. Use the answer choices [A-C] to explain what will happen as the polymerase chain reaction proceeds. Answers may be used more than once or not at all.
Hi. You did not provide any response options. However, a PCR reaction proceeds as follows.
After the primers are added to the test tube containing the PCR components. This tube is placed in a device called a thermocycler. At that moment, the stage called denaturation will begin, where the thermocycler increases the temperature to the point of breaking the hydrogen bonds that hold the two strands of DNA together. The thermal cycler increases the temperature up to 96°C.
After that, the second step of the reaction begins. At that moment, the thermal cycler lowers the temperature to 55º - 65ºC, which is the ideal temperature for the primers to be able to attach themselves to the DNA strands, preparing them for the presence of the polymerase.
After that, the thermocycler raises the temperature to 72ºC, which is the ideal temperature for the DNA polymerase to work. At this stage, the DNA polymerase will use the DNA strand and the primer to build a new DNA strand, which will be annealed to the DNA strand used as a template.
These three steps will be repeated about 35 times, generating many copies of DNA.
This week's imide synthesis involves two reactions. In the first reaction (24A), a(n) ________ bond is formed between the two reactants. Hint: What type of functional group is formed
Answer:
C - N Bond formation.
Explanation:
Imide synthesis is a chemical reaction in organic chemistry which consists of two acyl groups which bond to nitrogen atom. The compound structure is related to acid anhydrides. Imides are monoacyl which are used as valuable intermediates in organic synthesis.
sino may kuyang palaging nambibira
What is the pressure, in atm, exerted by 41.6 g oxygen in a 22.0L container at 30.0C ?
Answer:
1.47 atm
Explanation:
Step 1: Calculate the moles corresponding to 41.6 g of oxygen
The molar mass of oxygen is 32.00 g/mol.
41.6 g × 1 mol/32.00 g = 1.30 mol
Step 2: Convert 30.0 °C to Kelvin
We will use the following expression.
K = °C + 273.15 = 30.0 + 273.15 = 303.2 K
Step 3: Calculate the pressure exerted by the oxygen
We will use the ideal gas equation.
P × V = n × R × T
P = n × R × T / V
P = 1.30 mol × (0.0821 atm.L/mol.L) × 303.2 K / 22.0 L = 1.47 atm
What happens when you increase the pressure on the following
reaction
2X(g) + 3Y(g) --> 5Z(g) + heat
Answer:
When pressure increases, there is no effect on the reaction because volume is constant.
Please Help !! This is an Earth science lab question.
Explain why erosion occurs on the outside of a meander and deposition on the inside of a meander.
Answer:
The sideways movement occurs because the maximum velocity of the stream shifts toward the outside of the bend, causing erosion of the outer bank. At the same time the reduced current at the inside of the meander results in the deposition of coarse sediment, especially sand
A 250ml sample of sir at 373.15k is warmed at 473.15 at constant pressure. What is the volume of the air sample at the new temperature
Answer:
317 mL.
Explanation:
From the question given above, the following data were obtained:
Initial volume (V₁) = 250 mL
Initial temperature (T₁) = 373.15 K
Final temperature (T₂) = 473.15 K
Pressure = Constant
Final volume (V₂) =?
The final volume of the air sample can be obtained by using the Charles' law equation as illustrated below:
V₁/T₁ = V₂/T₂
250 / 373.15 = V₂ / 473.15
Cross multiply
373.15 × V₂ = 250 × 473.15
373.15 × V₂ = 118287.5
Divide both side by 373.15
V₂ = 118287.5 / 373.15
V₂ = 317 mL
Therefore, the final volume of the air sample is 317 mL
Give two ways to make salt conduct.
Answer:
I think u willl get the answer fast in......
Answer:
this is because when a salt dissolves, its dissociated ions can move freely in solution, allowing a charge to flow. The resulting solution will conduct electricity because it contains ions.
Explanation:
ASAP!!!!! The data table below shows a person’s heart rate measured in beats per minute (bpm) at five different times in the beginning of a day. What causes the change in heart rate over time?
1. tired
2. increased activity
3. passing of time
4. forgetting to eat
Determine the empirical formula of a compound having the following percent composition by mass: K: 24.74%; Mn: 34.76%; O: 40.50%
Answer: The empirical formula of the compound is [tex]KMnO_4[/tex]
Explanation:
The empirical formula is the chemical formula of the simplest ratio of the number of atoms of each element present in a compound.
The number of moles is defined as the ratio of the mass of a substance to its molar mass. The equation used is:
[tex]\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}[/tex] ......(1)
Let the mass of the compound be 100 g
Given values:
% of K = 24.7%
% of Mn = 34.76%
% of O = 40.50%
Mass of K = 24.7 g
Mass of Mn = 34.76 g
Mass of O = 40.50 g
To calculate the empirical formula of a compound, few steps need to be followed:
Step 1: Calculating the number of moles of each elementWe know:
Molar mass of K = 39.10 g/mol
Molar mass of Mn = 54.94 g/mol
Molar mass of O = 16 g/mol
Putting values in equation 1, we get:
[tex]\text{Moles of K}=\frac{24.7g}{39.10g/mol}=0.632 mol[/tex]
[tex]\text{Moles of Mn}=\frac{34.76g}{54.94g/mol}=0.633 mol[/tex]
[tex]\text{Moles of O}=\frac{40.50g}{16g/mol}=2.53 mol[/tex]
Step 2: Calculating the mole fraction of each element by dividing the calculated moles by the least calculated number of moles that is 0.632 moles[tex]\text{Mole fraction of K}=\frac{0.632}{0.632}=1[/tex]
[tex]\text{Mole fraction of Mn}=\frac{0.633}{0.632}=1[/tex]
[tex]\text{Mole fraction of O}=\frac{2.53}{0.632}=4[/tex]
Step 3: Writing the mole fraction as the subscripts of each of the elementThe empirical formula of the compound becomes [tex]K_1Mn_1O_4=KMnO_4[/tex]
Hence, the empirical formula of the compound is [tex]KMnO_4[/tex]
The empirical formula of the compound is KMnO₄
Data obtained from the question Potassium (K) = 24.74%Manganese (Mn) = 34.76%Oxygen (O) = 40.50%Empirical formula =? How to determine the empirical formulaDivide by their molar mass
K = 24.74 / 39 = 0.634
Mn = 34.76 / 55 = 0.632
O = 40.50 / 16 = 2.531
Divide by the smallest
K = 0.634 / 0.632 = 1
Mn = 0.632 / 0.632 = 1
O = 2.531 / 0.632 = 4
Therefore, the empirical formula of the compound is KMnO₄
Learn more about empirical formula:
https://brainly.com/question/24297883
How many moles of AICI3 are produced?
Answer:
please correct it, the question is incomplete
Write the molecular formula for the compound that exhibits a molecular ion at M+ = 112.0499. Assume that C, H, N, and O might be present, and use the exact masses below: Exact mass of carbon = 12.000 Exact mass of hydrogen = 1.0078 Exact mass of nitrogen = 14.003 Exact mass of oxygen = 15.995 (The order of atoms should be carbon, then hydrogen, then the others in alphabetical order. If there is more than one answer, just give one. ) Molecular formula:
Answer:
C₅H₈N₂O
Explanation:
The molecular formula denotes the various forms of atoms contained in a molecule at a particular fixed proportion.
The molecular ion M⁺ = 112.0499
and the exact mass values are given as follows:
C = 12.000
H = 1.0078
N = 14.003
O = 15.995
By assumption:
C = 12.000 × 5 = 60.0000
H = 1.0078 × 8 = 1.0078
N = 14.003 × 2 = 28.0060
O = 15.995 × 1 = 15.9950
= 112.0634
This is approximtely equal to 112.0499.
As such the Molecular formula for the compound = C₅H₈N₂O
Determine the electron geometry, molecular geometry, and idealized bond angles for each of the following molecules. CF4CF4 NF3NF3 OF2OF2 H2SH2S In which cases do you expect deviations from the idealized bond angle
Answer:
CF4
Molecular geometry- tetrahedral
Electron geometry- tetrahedral
NF3
-molecular geometry - trigonal pyramidal
Electron geometry - tetrahedral
OF2
Molecular geometry - bent
Molecular geometry - tetrahedral
H2S
Molecular geometry- bent
Electron geometry - tetrahedral
Explanation:
According to Valence Shell Electron Pair Repulsion Theory, the shape of a molecule depends on the number of electron pairs on the valence shell of the central atom in the molecule.
For all the compounds listed, the central atom has four points of electron density. This correspond to a tetrahedra electron pair geometry. The presence of lone pairs on the central atom of OF2,NF3 and H2S accounts for the departure of the observed molecular geometry from the geometry and idealized bond angle predicted on the basis of the VSEPR theory.
Which statement best describes the intermolecular forces between H2
molecules and NH3 molecules in the liquid phase?
A. Dipole-dipole forces are the strongest force between H2
molecules, and Van der Waals forces are the strongest force
between NH3 molecules.
B. Van der Waals forces are the strongest force between H2
molecules, and hydrogen bonding is the strongest force between
the NH3 molecules.
C. Hydrogen bonding is the strongest force between H, molecules
and between NH3 molecules.
D. Van der Waals forces are the strongest force between H2
molecules and between NH3 molecules.
Answer:
D. Van der Waals forces are the strongest force between H2
molecules and between NH3 molecules.
Explanation:
Van der Waal’s forces are the forces which arises due to disturbance in the electron density of the molecule.
These are usually found in non polar molecules. Hence N2 is said to exhibit this force.
Out of these Van der Waals is the weakest force.
An unknown element, X, has an atomic mass of 107.868 amu. The X-109 isotope (108.905 amu) is 48.16%. What is the amu of the other isotope (report final answer to the correct number of significant figures)
Answer:
106.905 amu is the mass of the other isotope
Explanation:
The atomic mass of an element is the sum of the masses of the isotopes multiplied by its abundance. The atomic mass of an element X with 2 isotopes is:
X = X-109*i + X-107*i
Where X is the atomic mass = 107.868 amu
X-109 = 108.905amu, i = 48.16% = 0.4816
X-107 = ?, i = 1-0.4816 = 0.5184
Replacing:
107.868amu = 108.905amu*0.4816 + X-107*0.5184
55.4194 = X-107*0.5184
106.905 = X-107
106.905 amu is the mass of the other isotopePlease select the word from the list that best fits the definition
Include skin, the respiratory system, the circulatory system, and inflammation
A. antibody
B. antigen
C.Natural Defences
D.active immunity
Answer:
I choose D option because may be it's correct
I believe it is c
Explanation:
because if u think about it and also do some research you would see that the circulatory system is a strong part of your body which can help u through natural defences if this sounds weird it's all in research but if it ain't c dont blame me for ruining your life- lol but yeah I think its c
C8H18+O2=CO2+H2O. Balance this equation and identify the number H2O molecules formed when 6 molecules of C8H18 react with 75 molecules of oxygen
Answer: 54 molecules of water will be formed in the reaction.
Explanation:
A balanced chemical equation is one where all the individual atoms are equal on both sides of the reaction. It follows the law of conservation of mass.
For the given unbalanced chemical equation, the balanced equation follows:
[tex]2C_8H_{18}+25O_2\rightarrow 16CO_2+18H_2O[/tex]
We are given:
Molecules of [tex]C_8H_{18}[/tex] = 6
Molecules of [tex]O_2[/tex] = 75
By the stoichiometry of the reaction:
If 2 molecules of [tex]C_8H_{18}[/tex] produces 18 molecules of water
So, 6 molecules of [tex]C_8H_{18}[/tex] will produce = [tex]\frac{18}{2}\times 6=54[/tex] molecules of water
Hence, 54 molecules of water will be formed in the reaction.
Make tag question.
neither of them plays cricket,......?
Answer:
neither of them plays cricket,does anyone?
Explanation:
I know you will think I its weird but it is the rule of grammar and 100% correct!
Answer:
neither of them plays cricket, do you?
Explanation:
What other reactions is taking place?
When the nuclide polonium-218 undergoes alpha decay:
a. The name of the product nuclide is _____.
b. The symbol for the product nuclide is _____.
Write a balanced nuclear equation for the following: The nuclide polonium-218 undergoes alpha emission.
Answer:
a): The name of the product nuclide is lead-214
b): The symbol of the product nuclide is Pb-218
Explanation:
There are three types of decay processes:
Alpha decayBeta decayGamma decayAlpha decay is the decay process that happens when a heavy nucleus decays into a light nucleus with the release of an alpha particle. This alpha particle carries a charge of +2 units and has a mass of 4 units. It is also known as the helium nucleus. The general equation for this decay process is:
[tex]_Z^A\textrm{X} → _{Z-2}^{A-4}\textrm{Y}+_2^4\alpha[/tex]
The nuclear equation for the alpha decay of Po-218 follows:
[tex]_{84}^{218}\textrm{Po}\rightarrow _{82}^{214}\textrm{Pb}+_2^4\alpha[/tex]
Hence, the name of the product nuclide is lead-214 and the symbol is Pb-218.
The information code that an organism inherits can best be referred to as its -
O A genotype
B. territory
C. species
D. kingdom
Answer:
it will be no.A genotype
Boric acid, B(OH)3, acts as an acid in water, but does not do so via ionization of a proton from boric acid. Use a balanced chemical equation to show why boric acid may be described as an acid in water.
Answer:
B(OH)₃ + H₂O = B(OH)₄⁻ + H⁺
Explanation:
Let's consider Arrhenius acid-base theory:
An acid is a substance that in aqueous media releases H⁺.A base is a substance that in aqueous media releases OH⁻.Boric acid, B(OH)₃ reacts with water according to the following equation.
B(OH)₃ + H₂O = B(OH)₄⁻ + H⁺
As we can see, boric acid releases H⁺ in aqueous media. Thus, it is an acid.
What is the total number of atoms in one formula unit of MgSO4.7H2O?
Answer:
11.
O4 means 4 atoms of oxygen. H2O
has one atom of oxygen, so seven "units" of
H2O has 7.
