Answer:
pKa = 4.89.
Explanation:
We can solve this problem by using the Henderson-Hasselbach equation, which states:
pH = pKa + log [tex]\frac{[A^-]}{[HA]}[/tex]
In this case [A⁻] is the concentration of sodium benzoate and [HA] is the concentration of benzoic acid.
We input the given data:
4.63 = pKa + log [tex]\frac{0.16}{0.29}[/tex]
And solve for pKa:
pKa = 4.89
(URGENT FOR BRAINLIEST!!)
The diagram below shows the movement of Earth plates.
The picture shows two Earth plates one beside the other. The plate on the left is shown moving towards the right and the plate
Which of these features is most likely formed as a result of the movement of Earth plates shown in the diagram? (2 points)
a canyon
a fault
a mountain
a ridge
Answer:
mountain
Explanation:
when plates move towards each other they create mountains
What is the change in the freezing point of a solution made by dissolving 14.7 g of
C6H1206 into 150 ml of water? Answer in 2 decimal.
The density of water is 1.00 g/ml and and Kf = 1.86 °C/m
The change in freezing point is 1.02°C
The change in the freezing point (ΔTf) is calculated from the following equation:
ΔTf = i x Kf x m
Given:
i = 1 (Van't Hoff factor, is equal to 1 because the solute is a nonelectrolyte)
Kf = 1.86°C/m (Freezing point constant of the solvent)
m = molality
We have to calculate the molality (m), which is equal to the moles of solute in 1 kg of solvent:
m = moles solute/ kg solvent
The solute is C₆H₁₂O₆. Thus, we calculate the moles of solute by dividing the mass into its molecular weight (Mw):
Mw(C₆H₁₂O) = (12 g/mol C x 6) + ( 1 g/mol H x 12) + (16 g/mol O x 6) = 180 g/mol
moles solute = mass C₆H₁₂O/Mw(C₆H₁₂O) = 14.7 g/(180 g/mol) = 0.082 mol
The solvent is water. Its mass (in kg) is obtained from the volume and the density, as follows:
kg solvent = V x density = 150 mL x 1.00 g/mL x 1 kg/1000 g = 0.15 kg
Now, we calculate the molality (m):
m = moles of solute/kg solvent = 0.082 mol/(0.15 kg) = 0.546 m
Finally, we calculate the change in freezing point:
ΔTf = i x Kf x m = 1 x 1.86°C/m x 0.546 m = 1.02°C
To learn more about freezing point depression, you can visit this content:
https://brainly.com/question/4258941
A) Draw a conclusion about the relationship between enzyme activity and reaction temperature.
B) Provide an explanation for why we see a flattening of the curve for the 75 degree reaction after 3 minutes.
Answer:
Direct relationship.
Explanation:
There is direct relationship between enzyme activity and temperature of reaction. Direct relationship means if one factor is increases the other factor is also increase and vice versa. In chemical reactions, the rate of an enzyme action increases as the temperature of the chemical reaction also increases. we see a flattening of the curve for the 75 degree reaction after 3 minutes because the enzyme action is not working at that temperature or in other words, this temperature is not suitable for the enzyme activity.
Sodium acetate
NaC2H3O2
SC2H3O2
Na2C2H3O2
Answer:
Sodium acetate is NaC2H3O2
Answer:
The answer is A for the lazy people.
Karl-Anthony is trying to plate gold onto his silver ring. He constructs an electrolytic cell using his ring as one of the electrodes. He runs this cell for 94.3 minutes at 205.3 mA. How many moles of electrons were transferred in this process
Answer:
0.012 moles of electrons were transferred
Explanation:
We can find the number of electrons transferred from the time in seconds and the current in Amperes using the equation:
n = I*t / F
Where n are moles of electrons transferred
I is current in Amperes = 0.2053A
t is time in seconds:
94.3min*(60s/1min) = 5658s
F is faraday constant 96485A*s/mol
Replacing:
n = 0.2053A*5658s / 96485A*s/mol
n = 0.012 moles of electrons were transferred
Moles are the mass per unit molar mass of compound. The number of moles of electrons that are transferred is 0.012 moles.
What is an electrolytic cell?An electrolytic cell is a type of electrochemical cell that uses electrical energy from external sources to conduct the chemical energy in a cell.
The moles transferred in electrolytic cells are measured as:
[tex]\rm n = \rm \dfrac{I\times t}{F}[/tex]
Given,
Current (I) in amperes = 0.2053 A
Time (t) in seconds = 5658 sec
Faraday constant (F) = 96485 A -s/mol
Substituting values in the equation above moles (n) can be calculated as:
[tex]\begin{aligned} \rm n &= \dfrac{ 0.2053 \times 5658 }{96485}\\\\&= 0.012 \;\rm mol\end{aligned}[/tex]
Therefore, 0.012 moles are transferred in this process.
Learn more about electrolytic cells here:
https://brainly.com/question/22514717
Question 4
18 g of carbon dioxide contains how many oxygen atoms?
Answer:
4.92×10²³ atoms of oxygen.
Explanation:
We'll begin by calculating the number of mole of oxygen in 1 mole of CO₂. This can be obtained as follow:
1 mole of CO₂ contains 2 mole of oxygen.
1 mole of CO₂ = 12 + (2×16)
= 12 + 32
= 44 g
Thus,
44 g of CO₂ contains 2 moles of oxygen.
Next, we shall determine the number of mole of oxygen in 18 g of CO₂. This can be obtained as follow:
44 g of CO₂ contains 2 moles of oxygen.
Therefore, 18 g of CO₂ will contain
= (18 × 2)/ 44 = 0.818 mole of oxygen.
Finally, we shall determine the number of atoms in 0.818 mole of oxygen. This can be obtained as follow:
From Avogadro's hypothesis,
1 mole = 6.02×10²³ atoms.
Therefore,
0.818 mole = 0.818 × 6.02×10²³ atoms.
0.818 mole of oxygen = 4.92×10²³ atoms.
Thus, 18 g of CO₂ contains 4.92×10²³ atoms of oxygen.
A nuclease enzyme breaks the covalent bond originally connecting the phosphate to the 5' carbon in a nucleic acid. After allowing this enzyme to completely digest the nucleic acid down to monomers, you perform tests to determine where the phosphate is attached to each monomer. Where do you expect to find this phosphate
Answer:
The phosphate will remain attached to the 5' carbon of the deoxy or the ribose sugar in the nucleic acid monomers.
Explanation:
The structure of nucleic acid polymers is built up from monomers of nucleotides.
A nucleotide consists of a sugar backbone which is either a ribose or deoxyribose sugar, a nitogenous base which is either a purine or pyrimidine, and a phosphate group. The nitrogenous base is attached to the carbon number 1 or C-1 of the sugar backbone by a covalent bond. The phosphate group on the other hand is covalently attached to the carbon number 5 or 5' carbon of the sugar backbone.
When polymers of nucleic acids are formed, the phosphate at the 5' carbon of the sugar backbone is covalently linked in a phosphodiester bond to the 3' carbon of the sugar backbone in another nucleotide molecule, thus extending the strands of the nucleic acid molecule.
Nucleases are enzymes that break down the phosphodiseter bonds in nucleic acids resulting in nucleotide monomers. After complete digestion ofmthe nucleic acid polymer by nucleases, the phosphate will remain attached to the 5' carbon of the deoxy or the ribose sugar in the nucleic acid monomers.
A Single Orbital With Two Lobes At 90°In A Single Plane And A Node In The Center Would Likely Be Found Where?
a.4s
b.4p
c.4d
d. it would not be found in any of these
e.4f
8. Benzene is an aromatic hydrocarbon with molecular formula C6H6. a) Draw the ring structure of Benzene. [1] how will you prepare benzene from phenol
When phenol is heated with zinc dust benzene is obtained.
I don’t know what Ksp and Kf are stand for?
Answer:
Sorry but I know only what ksf stand for
Explanation:
Ksf stand for solubility product constant
Answer:
ksp stands for solubility product constant .
kf stands for molal freezing point depression constant ..
Explanation:
KSP = The solubility product constant, Ksp, is the equilibrium constant for a solid substance dissolving in an aqueous solution. It represents the level at which a solute dissolves in solution. The more soluble a substance is, the higher the Ksp value it has .
KF = Kf is a constant for a given solvent. Kf is called the molal freezing point depression constant and represents how many degrees the freezing point of the solvent will change when 1.00 mole of a nonvolatile nonionizing (nondissociating) solute dissolves in one kilogram of solvent.
Determine
the
number
of grams of C4H10
that
are
required
to
completely
react
to
produce 8.70 mol of CO2
according
to
the
following
combustion
reaction:
2 C₄H₁₀(g)
+
13 O₂(g)
→
8 CO₂(g)
+
10 H₂O(g)
Answer:
8 CO₂(g)
Explanation:
just took the exam
5. For Sodium, the Work Function is listed as 2.75 eV but the Ionization Energy is listed as 5.14 eV. Is one of the experiments wrong? Give a possible explanation as to this difference in the minimum energy needed to eject or free an electron from Sodium.
Answer:
See explanation
Explanation:
The work function of a metal is defined as that minimum energy which is required to remove one electron from the surface of a metal when it is irradiated with a photon of light. The work function is different for different metals.
The ionization energy of a metal is the energy required to remove an electron from an atom. It depends on the position of the electron within the atom.
The work function specifically refers to the energy required to remove an electron from the conduction band of a metal. Hence, the work function is always lower than the ionization energy.
which list only includes terms that describe... both questions please
The terms that describe sodium atom are;
AtomelementPure substanceThe terms that describe propane gas are;
MoleculeCompoundPure substanceSodium can be described as an element found in the periodic table. Sodium can also be described as an atom as in when we make the statement; 'an atom of sodium'. Sodium can also be regarded as a pure substance as in when we are referring to a substance composed only of sodium atoms.
On the other hand, propane gas can be regarded first as a compound because it is a combination of elements that are chemically combined together. We can also refer to 'a molecule of propane gas' since the substance is molecular in nature. Also, the pure gas (containing no impurity) can be regarded as a pure substance.
Learn more: https://brainly.com/question/13947925
The functional groups in an organic compound can frequently be deduced from its infrared absorption spectrum.
a. True
b. False
Answer:
a. True
Explanation:
The main information that gives an infrared absorption spectrum is the type of functional groups that are present in an organic compound. The infrared (IR) spectroscopy is based on the fact that functional groups absorb light in the IR region of the electromagnetic spectrum (approximately at 2,500-16,000 nm) and induces a vibrational excitation of the covalently bonded atoms in the group. The vibration of the atoms can be of different types, such as stretching, bending, etc. Each functional group (such as the carbonyl group) in an organic compound absorbs at a specific IR frequency so they can be distinguished from an IR spectrum.
I bet no one can solve this
If an electric current of 8.50 A flows for 3.75 hours through an electrolytic cell containing copper-sulfate (CuSO4) solution, then how much copper is deposited on the cathode (the negative electrode) of the cell? (Copper ions carry two units of positive elementary charge, and the atomic mass of copper is 63.5 g/mol.)
PLEASE HELP ASAP
Use the equation below to answer the following questions.
2Al(s) + 3Cu(NO3)2(aq) 3Cu(s) + 2Al(NO3)3(aq)
Determine the oxidation state of the atoms in the equation's reactants and products: (6 points)
Oxidation state of Al in reactant:
in product:
Oxidation state of Cu in reactant:
in product:
Oxidation state of N in reactant:
in product:
Oxidation state of O in reactant:
in product:
Explain why this is a redox reaction.
Thank you!
Answer:
See explanation
Explanation:
A redox reaction equation shows a gain/loss of electrons from left to right in a reaction. In a redox reaction, a specie looses electrons while another specie gains electrons.
Considering the equation; 2Al(s) + 3Cu(NO3)2(aq) -----> 3Cu(s) + 2Al(NO3)3(aq)
The oxidation state of Al reactant is zero since the oxidation state of all uncombined elements is zero. The oxidation state of All in the product is +3
The oxidation state of the copper in the reactant is +2. The oxidation state of copper in the product is zero.
The oxidation state of N in the reactant and product is +5.
The oxidation state of oxygen in the reactant and product is (-2).
This is a redox reaction because from left to right, Al was oxidized (oxidation number increased from zero to +3) while Cu was reduced (oxidation number decreased from +2 to zero).
WHAT WOULD THE RIGHT OPTION??
how many resonance structures of benzene are known?
A) 3
B) 4
C) 5
D) 6
Answer:
C) 5
Step-by-step explaination:
Benzene has 5 resonance structures.
Three bonding pairs around a central atom results in a ________. A. octahedral B. trigonal planar compound C. tetrahedral compound D. linear compound
Answer:
B
Explanation:
because it is a trigonal planar compound
Three bonding pairs around a central atom results in a trigonal planar compound. Option B is correct.
In a trigonal planar arrangement, the central atom is surrounded by three bonding pairs of electrons, forming a flat, triangular shape. The bond angles between the bonding pairs are approximately 120 degrees.
This molecular geometry is observed when a molecule has a central atom with three bonded pairs and no lone pairs. Examples of compounds with trigonal planar geometry include boron trifluoride (BF₃) as well as formaldehyde (H₂CO).
The other options are not correct for a molecule with three bonding pairs;
Octahedral refers to a molecular geometry with six bonding pairs around a central atom.
Tetrahedral corresponds to a molecular geometry with four bonding pairs around a central atom.
Linear represents a molecular geometry with two bonding pairs around a central atom.
Hence, B. is the correct option.
To know more about bonding pairs here
https://brainly.com/question/32421783
#SPJ2
A runner completes the 300-meter dash in 38 seconds. What is the speed of the runner? Round your answer to the nearest tenth.
Answer:
x= 300m , 38s
answer is 7.9
Answer:
speed=distance/time
Explanation:
speed=300/38
=7.8947368421
to the nearest tenth=7.9
GIVING BRAINLIEST
Which equations are used to calculate the velocity of a wave?
O velocity = distance ~ time
velocity = wavelength x frequency
velocity = distance/time
velocity = wavelength/frequency
velocity = distance/time
velocity = wavelength x frequency
velocity = distance ~ time
velocity = wavelength/frequency
Answer:
velocity = distance/time
velocity = wavelength × frequency
Both of these are commonly known equations to calculate velocity with different variables.
State the different radiations emitted by radioactive elements.
Answer:
gamma rays , alpha particles , beta particles , neutrons
Identify the compound that possesses a permanent dipole. Please choose the correct answer from the following choices, and then select the submit answer button. Answer choices acetone, (CH3)2CO cyclohexane, C6H12 pentane, C5H12 methane, CH4.
Answer:
acetone, (CH3)2CO cyclohexane are the compound that possesses a permanent dipole
Explanation:
Permanent dipole describes the partial charge separation that can occur within a molecule along with the bond dat form between 2 different atoms
Which gas has the highest diffusing rate between nitrogen , oxygen , hydrogen and chlorine
Answer:
hydrogen
Explanation:
The gas with the least molecular weight effuses the fastest (Graham's Law). Hence, H gas has a higher rate of diffusion compared to N, O, and Cl.
So, Cl is the slowest when it comes to the rate of diffusion, because it has the highest molecular weight.
You are titrating 24.3 mL of 2.00 M HCl with 1.87 M NaOH. How much NaOH do you expect to have added when you reach the equivalence point?
26.0 mL
15.4 mL
13.4 mL
Answer:
26mL
Explanation:
NaOH+HCl= NaCl+H2O
nHCl=0.0243*2=0.0486
nNaOh=nHCl
VNaOH=0.0486/1.87=0.026l=26ml
Answer:
26.0 mL
Explanation:
5. How many moles are present in 4.20x10^24 atoms of Pb
Explanation:
[tex]57816 \: moles[/tex]
are present in 4.20x10^24 atoms of Pb
Answer:
7 moles
Explanation:
(4.2*10^24)/(6*10^23)=7
proteins contain
a. oxygen
b. nitrogen
c. hydrogen
Answer:
All of the above
Explanation:
Proteins contain a long chain of amino acids which are a chain of oxygen, nitrogen, carbon, hydrogen or sulfur.
HOPE THIS HELPED
arrange the metals sodium,copper, and magnesium in the decreasing order of their reactivity
Answer:
sodium>magenisium>copper
Which is the best interpretation of the two flat portions of the graph?
In those portions, the heat supplied to the substance by the heater does not lead to a temperature rise as intermolecular forces are broken.
When a substance is heated, we normally expect that its temperature will rise as a consequence.
However, heat may be supplied to a substance but its temperature does not rise owing to the fact that the heat energy supplied is used to break intermolecular bonds.
This occurs during fusion and boiling. The heat supplied at these point does not result in temperature rise since it is used to break intermolecular bonds. The temperature remains steady during these processes as shown by the two flat portions on the graph in the image attached to the question. This heat supplied is known as the latent heat.
For more about latent heat, see:
https://brainly.com/question/19863536
Answer:
The answer for me was "These show where changes of state are occuring"
Explanation:
I got it right
Un sistema formado por una única sustancia, ¿será siempre homogéneo? ¿Porqué? Piensa a partir de las definiciones y trata de corroborar o negar usando ejemplos concretos.
Una sustancia homogénea es una sustancia que se compone de una sola fase.
Recordemos que definimos una fase en química como "cantidad química y físicamente uniforme u homogénea de materia que se puede separar mecánicamente de una mezcla no homogénea y que puede consistir en una sola sustancia o una mezcla de sustancias" según Ecyclopedia Britiannica.
El hecho de que un sistema esté compuesto por una sola sustancia no lo hace es autóctono. A veces, un sistema puede estar compuesto por partículas sólidas de una sustancia en equilibrio con su líquido. El sistema contiene solo una sustancia pero en diferentes fases, por lo tanto, el sistema contiene una sustancia pero no es homogéneo.
Por tanto, el hecho de que un sistema contenga una sola sustancia no significa necesariamente que sea homogéneo.
https://brainly.com/question/9970247
you want to remove as much CO2 gas as possible from a water solution. Which of the following treatments would be most effective?
Answer:
Aerate solution
Explanation:
aerate solution is the best way to remove CO2 from water (Carbon dioxide in the water that does not form bicarbonates is “uncombined” and can be removed by aeration).
