Answer:
its d
Explanation:
i did the quiz
The OH⁻ concentration in an aqueous solution at 25 °C is 7.9 × 10⁻³M, then the concentration of H⁺ ion is 1.28 × 10⁻¹²M.
How do we calculate [H⁺]?Concentration of H⁺ will be calculated by using the below equation as:
pH = -log[H⁺]
Or [H⁺] = [tex]10^{-pH}[/tex]
Also we know the realation pH + pOH = 14 and pOH will be calculated as:
pOH = -log[OH⁻]
Given that, [OH⁻] = 7.9 × 10⁻³M
pOH = -log(7.9 × 10⁻³)
pOH = -(-2.102) = 2.102
Putting this value in above realation equation, we get
pH = 14 - 2.102 = 11.89
Now calculating the concentration of H⁺ by using this pH as:
[H⁺] = [tex]10^{-11.89}[/tex]
[H⁺] = 1.28 × 10⁻¹²M
Hence required concentration of [H⁺] is 1.28 × 10⁻¹²M.
To know more about pH & pOH, visit the below link:
https://brainly.com/question/17144456
1 point
Which element requires the least amount of energy to remove its valence electron(s)?
barium
chlorine
oxygen
carbon
What characteristic of life is demonstrated by maintaining a stable pH?
Answer:
Living Things Maintain Stable Internal Conditions When any living organism gets thrown off balance, its body or cells help it return to normal. In other words, living organisms have the ability to keep a stable internal environment. Maintaining a balance inside the body or cells of organisms is known as homeostasis.
Explanation:
What is the best-known feature of sedimentary
rocks?
A. ripple marks
B. fossils
C. graded bedding
D. cross-bedding
Answer:
option is (b)
Explanation:
please mark me as brilliant
We can identify unknown elements in a star by matching the ___________ spectrum of the star to those of known elements. *
mass
emission
atoms
Which pattern on the periodic table is correctly predicted below?
Groups determine the number of valance electrons and periods determine the number of energy levels
Groups determine the number of energy levels and periods determine the number of valence electrons
Groups determine the number of protons, and periods determine energy levels
Groups determine the number of neutrons, and periods determine valence
Plzz
PLEASE HELP !!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Which of the following does NOT increase with increasing temperature?
a kinetic energy
b thermal energy
c potential energy
d none of the above
Answer:
Explanation:
Potential energy
The amount of force needed to keep a 10 kg box moving at a constant
speed of 0.4 m/s on frictionless ice is *
ON,
0.04N
40 N
1.4 N
Answer:
ON
Explanation:
Frictional force is a force that opposes the motion of body. It is because of friction that motion can be controlled and even walking is made possible.
Now, on a frictionless surface, there is no opposition to motion. Therefore, to keep the body moving there is no force required.
If surface lacks friction, motion will continue perpetually without any hinderance.which type of rection has the general formuial ab+cd
PLEASE HELP!! (I will mark brainiest) (REAL ANSWERS ONLY PLEASE!)
In one paragraph, using your own words, describe the structure of DNA using the following terms: phosphate, sugar, pyrimidines, purines, and bonding.
The phosphate group of one nucleotide bonds covalently with the sugar molecule of the next nucleotide, and so on, forming a long polymer of nucleotide monomers. The sugar–phosphate groups line up in a “backbone” for each single strand of DNA, and the nucleotide bases stick out from this backbone. The carbon atoms of the five-carbon sugar are numbered clockwise from the oxygen as 1′, 2′, 3′, 4′, and 5′ (1′ is read as “one prime”). The phosphate group is attached to the 5′ carbon of one nucleotide and the 3′ carbon of the next nucleotide. In its natural state, each DNA molecule is actually composed of two single strands held together along their length with hydrogen bonds between the bases.
Answer:
Explanation:
The discovery that DNA is the prime genetic molecule, carrying all the hereditary information within chromosomes, immediately focused attention on its structure. It was hoped that knowledge
of the structure would reveal how DNA carries the genetic messages that are replicated when chromosomes divide to produce two identical copies of themselves. During the late 1940s and early 1950s, several research groups in the United States and in Europe engaged in serious efforts—both cooperative and rival—to understand how the atoms of DNA are linked together by covalent bonds and how the resulting molecules are arranged in three-dimensional space. Not surprisingly, there initially were fears that DNA might have very complicated and perhaps bizarre structures that differed radically from one gene to another. Great relief, if not general elation, was thus expressed when the fundamental DNA structure was found to be the double helix. It told us that all genes have roughly the same three-dimensional form and that the differences between two genes reside in the order and number of their four nucleotide building blocks along the complementary strands.
Now, some 50 years after the discovery of the double helix, this simple description of the genetic material remains true and has not had to be ap- preciably altered to accommodate new findings. Nevertheless, we have come to realize that the structure of DNA is not quite as uniform as was first thought. For example, the chromosome of some small viruses have single-stranded, not double-stranded, molecules. Moreover, the precise orientation of the base pairs varies slightly from base pair to base pair in a manner that is influenced by the local DNA sequence. Some DNA se- quences even permit the double helix to twist in the left-handed sense, as opposed to the right-handed sense originally formulated for DNA’s general structure. And while some DNA molecules are linear, others are circular. Still additional complexity comes from the supercoiling (further twisting) of the double helix, often around cores of DNA-binding proteins.
Likewise, we now realize that RNA, which at first glance appears to be very similar to DNA, has its own distinctive structural features. It is principally found as a single-stranded molecule. Yet by means of intra-strand base pairing, RNA exhibits extensive double-helical character and is capable of folding into a wealth of diverse tertiary structures. These structures are full of surprises, such as non-classical base pairs, base-backbone interactions, and knot-like configurations. Most remarkable of all, and of profound evolutionary significance, some RNA molecules are enzymes that carry out reactions that are at the core of information transfer from nucleic acid to protein.
Clearly, the structures of DNA and RNA are richer and more intricate than was at first appreciated. Indeed, there is no one generic structure for DNA and RNA. As we shall see in this chapter, there are in fact vari- ations on common themes of structure that arise from the unique physi- cal, chemical, and topological properties of the polynucleotide chain
Which method of heat transfer allows you to fry an egg in a frying pan on the stove?
Answer:
Conduction
Explanation:
Answer:
Conduction is correct
Explanation:
predict how many moles of nh3 would be made if 6.00 moles of h2 were used N2
Answer:
4 moles
Explanation:
The equation is 3H2 + N2 → 2NH3
so the ratio of moles would be
2:3 or 2/3
so 6*2/3 which is 4
hope this helped.
Answer:
4moles
Explanation:
Given parameters:
Number of moles of H₂ used = 6moles
Equation of the reaction:
N₂ + 3H₂ → 2NH₃
3 mole of H₂ was used to produce 2 mole of NH₃;
6 mole of H₂ will produce [tex]\frac{6x2}{3}[/tex] = 4 moles of NH₃
The number of moles of NH₃ produced is 4moles
What is the relationship between temperature and pressure
what mass of calcium chloride will be produced from 3.750 moles of hcl reacting with ca(oh)2
Answer:
208.125g
Explanation:
Given parameters:
Number of moles of HCl = 3.75moles
Unknown:
Mass of CaCl₂ that will be produced = ?
Solution:
The reaction equation is given as:
2HCl + Ca(OH)₂ → CaCl₂ + 2H₂O
Now, to find the mass of CaCl₂, we have to work from the known to the unknown.
The known specie here is the number of moles of HCl;
2 mole of HCl will produce 1 mole of CaCl₂
3.75moles of HCl will produce [tex]\frac{3.75}{2}[/tex] = 1.875moles
The mass of CaCl₂;
Mass of CaCl₂ = number of moles of CaCl₂ x molar mass
Molar mass of CaCl₂ = 40 + 2(35.5) = 111g/mol
Mass of CaCl₂ = 1.875 x 111 = 208.125g
A scientist is considering formaldehyde (HCHO) for use in an experiment. She is studying the strength of triple bonds in molecules. Is
ormaldehyde a good choice for her to use? Why?
A. Yes, HCHO has three triple bonds.
B. Yes, HCHO has one triple bond.
C. No, HCHO has a double bond but no triple bonds.
D. No, HCHO has only single bonds.
A rock rolls down a hill. Which form of energy is this an example of?
Chemical
Electrical
Mechanical
Thermal
Answer:
Mechanical
Explanation:
chemical
Explanation:
I took test 2020
A neutral atom becomes a positive ion when it
Answer:
Neutral atoms can be turned into positively charged ions by removing one or more electrons.
Explanation:
If there is an atom that has 9 protons and 9 electrons, removing an electron from the atom will gain a postive charge.
A binary molecule consists of how many atoms?
O1
02
3
4
Answer:
2
Explanation:
BIonary bi means 2
i hope this helps :)
In metallic bonds, the mobile electrons surrounding the positive ions are called a(n)
what is the most likely oxidation state of nitrogen
In comparing the chemistry of the amines with alcohols and ethers, we discover many classes of related compounds in which nitrogen assumes higher oxidation states, in contrast to limited oxidation states of oxygen. In this context, keep in mind that the oxidation state of elemental oxygen (O 2) and nitrogen (N 2) is defined as zero.
Answer:
-3
Explanation:
How many orbitals in an atom can have each of the following designations?
(a) 4s
(b) 5f
(c) 6p
(d) n=1
The three lines in this Lewis dot structure represent the.
A)
three valence electrons of dinitrous oxide.
B)
six electrons in the triple bond of diatomic nitrogen.
C)
three electrons joining two nitrogen atoms in a diatomic molecule.
D)
three double bonds between the valence electrons of diatomic nitrogen.
Answer:
B) . six electrons in the triple bond of diatomic nitrogen
Explanation:
The three line in this Lewis dot structure represents the six electrons in the triple bond of diatomic nitrogen.
Nitrogen is made up of 7 electrons with 5 valence ones.
A lewis structure is made up of the symbol of the element surrounded by dot to represent the valence electrons.
In this nitrogen molecule, both species share 6 electrons. This makes each nitrogen atom isoelectronic with neon.
Which of the following macromolecule is the main energy source for most living organisms?
A. Nucleic Acids
B. Carbohydrates
C. Lipids
D. Proteins
Answer:
Carbohydrates
Explanation:
Living things use carbohydrates as their main source of energy. The breakdown of sugars, such as glucose, supplies immediate energy for cell activities. Plants, some animals, and other organisms also use carbohydrates for structural purposes.
The density of ethanol, C 2H 5OH, is 0.789 g/mL. How many milliliters of ethanol are needed to produce 25.0 g of CO 2 according to the following chemical equation?
C 2H 5OH( l) + 3 O 2( g) → 2 CO 2( g) + 3 H 2O( l)
Answer:
11.1mL
Explanation:
The reaction expression is given as:
C₂H₅OH + 3O₂ → 2CO₂ + 3H₂O
Given parameters:
density of ethanol = 0.789g/mL
mass of CO₂ = 25g
Unknown:
Volume of ethanol = ?
Solution:
First find the number of moles of the CO₂ from the given mass;
Number of moles = [tex]\frac{mass}{molar mass}[/tex]
Molar mass of CO₂ = 12 + 2(16) = 44g/mol
Number of moles = [tex]\frac{25}{44}[/tex] = 0.57mol
Then;
Find the number of moles of ethanol used;
3 moles of CO₂ is produced from 1 mole of ethanol;
0.57mole of CO₂ will be produced from [tex]\frac{0.57}{3}[/tex] = 0.19mole of ethanol
Now;
Find the mass of the ethanol from the given mole;
Mass of ethanol = number of moles x molar mass
Molar mass of ethanol = 2(12) + 5(1) + 16 + 1 = 46g/mol
Mass of ethanol = 0.19 x 46 = 8.74g
Then;
Density is the mass per unit volume of a substance;
Density = [tex]\frac{mass}{volume}[/tex]
Volume = [tex]\frac{mass}{density}[/tex]
Volume = [tex]\frac{8.74}{0.789}[/tex] = 11.1mL
Matter is anything that has mass and takes up space (volume). How does volume change as matter changes state?
A. The density of matter remains the same, only energy of the atoms changes.
B. matter becomes more dense as it moves from solid to gas
C. Matter becomes less dense as it moves from gas to solid state
D. Matter becomes more dense as it moves from gas to solid state
Answer: D) Matter becomes more dense as it moves from gas to solid state
A gas expands to fill up the container of whatever shape or size. As it cools to a solid, the molecules get closer together and don't move as much (the molecules still will vibrate and move somewhat even in solid form). So effectively the volume of the object shrinks while the amount of mass stays the same. This is why the density increases when going from gas to solid.
What color do you get if you mix red and blue light?
Red and Green?
Blue and green?
What relationship do you find between frequency and energy?
What relationship do you find between wavelength and current flow?
What relationship do you find between light intensity and current flow?
Answer:
Purple light.
Yellow light.
Explanation:
Which one of the following is NOT a proper unit for frequency? *
m·s–1
Hz
s–1
1/s
Answer:
m*s⁻¹.
Explanation:
Hello!
In this case, since the frequency measures how repetitive an event is per unit of time, for instance the laps a car drives every 5 minutes or something similar, we can infer it has units of event/time; in such a way, the unit m*s⁻¹ is not a proper unit of frequency because it is a proper unit of velocity which is the distance traveled per unit of time.
In such a way, Hz (hertz), s⁻¹ and 1/s are possible ways frequency can be represented.
Best regards!
Gustavo and Beatriz are pushing on a door in opposite
directions. If the door does not move, the forces are
The net force in this scenario would be Answer: balanced and zero
Answer:
Correct
Explanation:
Balanced forces are always zero!
Answer:
Balanced
Zero
Explanation:
What force is causing The object to eventually stop moving
Answer:
Hey buddy, here is your answer. Hope it helps you.
Explanation:
The force stopping the object's motion might be an obvious one - the ground! Friction is a force that slows or stops motion. Friction is the resistance to motion created by two objects rubbing against each other (the sled and the snow, for instance). Even air causes friction.
We must __________ forces to calculate net force if the forces are going in OPPOSITE directions.
options:
add
or
subtract
Answer:
subtract
Explanation:
To find the net force of two bodies going in opposite directions, we must subtract the forces this is because they are not additive forces.
The net force is the resultant force acting on a body. This resultant force is the single force that will produce the same effects as all given forces. When forces are directed oppositely on a body, they are subtracted from each other to find the net force.g Lactate dehydrogenase is a tetrameric enzyme (144kDa) that catalyzes conversion of pyruvate into lactate to regenerate NAD in oxygen depleted muscles. a) Why in anaerobic conditions, is NADH oxidized by lactate dehydrogenase
Answer:
Kindly check the explanation.
Explanation:
NADH is oxidized anaerobic conditions by lactate dehydrogenase because in order to transform or change Pyruvate into Lactate it has to happen in an anaerobic condition that is where we hardly find oxygen(in the presence of no oxygen).
The chemical compound or say the enzyme known as lactate dehydrogenase gets its proton from NADH( in a REDOX type reaction). After getting the proton from NADH, it uses that to convert Pyruvate into Lactate.
NB: the conversion can also be done in aerobic condition but more ATP will be produced. With anaerobic condition, less ATO is produced and there is re-oxidation.
