A buffer solution of diclofenac (pKa= 4.15) is buffered at ph 5.5.
The Henderson-Hasselbalch equation is commonly used to calculate the pH of buffer solutions. Buffers are made up of a weak acid and a conjugate base. As a result, for a generic weak acid, we could call it HA, and its conjugate base would be A-. To calculate the pH of the buffer solution, find the pKa of the weak acid and multiply it by the log of the conjugate base concentration divided by the concentration of the weak acid.
First, we need to know the pKa of the weak acid, which is acetic acid.The Ka value is less than one because acetic acid is a weak acid. To find the pKa of acetic acid, we take the negative log of the Ka value. So the negative log of 1.8 times 10 to the negative fifth is equal to 4.74. So we can go back to the Henderson-Hasselbalch equation and write that the pH is equal to the pKa, which we just calculated to be 4.74 plus the log of the concentration of the conjugate base.
And therefore, the pH of the buffer solution is less than the pKa of the weak acid. And in the third example, the concentration of the weak acid was less than the concentration of the conjugate base.
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Describe the structure of the berilium atom
Answer:
Beryllium as 4 protons and 5 neutrons in its nucleus giving it an Atomic Number of 4 and an atomic mass of 9. An atom of Beryllium has only 2 electrons in its outer shell.
Which of the following pH values indicates a solution with the highest concentration of hydrogen ions? A. pH = 1, B. pH = 2, C. pH = 7, D. pH = 14.
A solution with a higher number of free hydrogen ions would have lesser pH than a solution having comparatively lower number of free hydrogen ions. Thus, the answer would be Option A i.e. pH = 1.
On the pH ( denoting potential or power of hydrogen) scale , the number which has the highest concentration of hydrogen ions must generally be 0. This represents or marks a chemical/solution with a hydrogen ion concentration of 1 mole/liter or a solution of 1 M (Molarity). Such high concentrations/numbers of hydrogen ions are typically only found in solutions/mixtures made with a strong acid when completely dissociates in water (hydrochloric acid is an example of such solution). We generally treat the pH scale from zero(0) to fourteen (14). For each pH unit, the concentration of hydrogen ions or the number of free hydrogen ions decreases by an order of 10. However, for a solution of pH of less than 0 to exist, a higher hydrogen ion concentration than 1 M concentration would be required.
The lowest known pH is -3.6 from which is achieved by extremely acidic mine water.
Thus, acids generally have high concentrations of hydrogen atoms.
Hence, the answer to the question would be an option with lowest pH score, which is option A.
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Predict the product(s) for the following reactions: (a) NaBH4
(b) CH3CH2OH
(CH3)2CHCH2CH2CH
NaBH4
CH3 COCH2CH3
CH3CH2OH
(c) CO₂CH3
1. LiAlH4, ether
(d) 2. H₂O
CO2CH3
NaBH4
CH3OH
A noteworthy skill of human chemists is the capacity to predict reactions' outcomes with considerable accuracy.
Can we predict chemical reactions?A noteworthy skill of human chemists is the capacity to predict reactions' outcomes with considerable accuracy.These predictions are, of course, grounded on a fundamental physical understanding, but they are unquestionably not the result of meticulous numerical analysis.See what transpires when the chemical splits into smaller, more recognizable products like water, carbon dioxide, or any of the gaseous elements to forecast the outcomes of such a reaction.Combining pure elements frequently results in synthesis reactions.many types of chemical reactions.synthetic processes decaying processes. answers that only replace one.replacement reactions are doubled.To learn more about chemical reactions refer
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Explain why your lung capacity and breathing rate are larger when you are exercising than when you are asleep
When exercising, the body requires more oxygen to fuel the muscles and produce energy. To meet this increased demand for oxygen, the lungs increase their capacity and breathing rate. This allows for more oxygen to be taken in with each breath and for the oxygen to be delivered to the muscles more quickly.
During exercise, the body's metabolism increases as the muscles need more energy to perform the exercises. As a result, the heart rate increases and the blood vessels dilate, allowing for more blood to flow through the body and deliver oxygen to the muscles. The lungs also respond to the increased demand for oxygen by increasing their capacity and breathing rate to take in more oxygen with each breath.
Additionally, the diaphragm and intercostal muscles that control the lungs' expansion and contraction also play an important role in this process. During exercise, these muscles work harder, allowing the lungs to expand more and take in more oxygen with each breath.
On the other hand, when you're asleep, the body's metabolism slows down and the muscles are at rest. So, the body doesn't need as much oxygen as it does during exercise. As a result, the lungs' capacity and breathing rate decrease, allowing for less oxygen to be taken in with each breath and for the oxygen to be delivered to the body more slowly.
In summary, when exercising the body requires more oxygen to fuel the muscles and produce energy, and the lungs increase their capacity and breathing rate to meet this increased demand for oxygen, allowing for more oxygen to be taken in with each breath and for the oxygen to be delivered to the muscles more quickly.
Usually people breathe more gradually while they are sleep, and as sleep stages progress, inhaling becomes more constant and less unpredictable. Nonetheless, studies have shown that when we are in the rapid eye movement (REM) sleep hormone, we also breathe more rapidly and unevenly.
Your lungs and cardiovascular system work quite hard while you exercise. They work together to bring oxygen into the system and get it to the working muscles. This helps your lungs work better by subsequently increases and fortifying the tissue surrounding them.
using standard heats of formation, calculate the standard enthalpy change for the following reaction.
We must determine standard enthalpy change using standard heat of formation. We are aware of the standard heat of graphite creation in order to answer that query.
One group of chemical elements can convert chemically into another through the process of reaction. Sol- We must follow their request and use the accepted temps of formation in this problem. In order to calculate a standard enthalpy change, we must use a standard heat of formation. As a result, in this scenario, we must establish the typical enthalpy change for the particular reaction. What is the advised reply to it, then? In this situation, we must determine the standard or enthalpy change. The result of mixing oxygen gas and solid graphite is c. As a result, gas is created. This is the answer to that reply. The usual heat of creation must be determined. This holds true.
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Sulfur dioxide reacts with oxygen to produce sulfur trioxide. Write the equation. Identify the limiting reagent when 20.0 g of SO2 react with 15.6 g of O2.
The equation related to reaction between Sulfur dioxide and oxygen to produce sulfur trioxide is 2SO[tex]_2[/tex](g) + O[tex]_2[/tex](g) [tex]\rightarrow[/tex] 2SO[tex]_3[/tex] (g). SO[tex]_2[/tex] is limiting reagent.
What is limiting reagent?The reactant that controls how much of the products are generated inside a chemical reaction is known as the limiting reagent. Since some of the other reactants remain that after limiting reagent has been used fully, it is occasionally discovered that they are in excess in the reactions. The theoretical yield is the most product that can theoretically be produced.
2SO[tex]_2[/tex](g) + O[tex]_2[/tex](g) [tex]\rightarrow[/tex] 2SO[tex]_3[/tex] (g)
moles of SO[tex]_2[/tex] =20.0 g / 64.07
=0.312moles
moles of O[tex]_2[/tex]= 15.6 g/32
=0.487moles
On dividing the moles by stoichiometry, out of O[tex]_2[/tex] and SO[tex]_2[/tex], SO[tex]_2[/tex] is limiting reagent.
Therefore, the equation related to reaction between Sulfur dioxide and oxygen to produce sulfur trioxide is 2SO[tex]_2[/tex](g) + O[tex]_2[/tex](g) [tex]\rightarrow[/tex] 2SO[tex]_3[/tex] (g). SO[tex]_2[/tex] is limiting reagent.
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How many molecules are in 2. 0 molecules?.
Two O molecules would refer to two individual molecules of O, which stands for oxygen. Oxygen is a diatomic molecule, which means that each molecule of oxygen is made up of two atoms of oxygen (O2). So, the number of molecules in two O molecules would be two.
Two O molecules refers to two individual molecules of oxygen, which is a diatomic molecule made up of two atoms of oxygen (O2). It's a number that represents the number of molecules.
Each molecule has two atoms of oxygen. So, the number of molecules in two O molecules would be two. The statement is talking about a quantity of molecules, not a physical object or a specific set of molecules. In other words, the number 2.0 or two in this context is a representation of the quantity of oxygen molecules, not a physical object with a specific number of molecules.
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Find the empirical formula for a compound with a molecular formula of C8H12.
Answer:
C2H3
Explanation:
The empirical formula is the simplest whole number ratio of atoms of each element in a compound while the molecular formula shows us the actual number of atoms of each element
Writing C8H12 in a ratio:
8 : 12
This can be simplified by dividing by a common factor present in both numbers
8 and 12 can be divided by 4
8 ÷ 4 = 2 and 12 ÷ 4 = 3, hence the ratio is:
2 : 3
This cannot be simplified any further
Thus, the empirical formula is C2H3
Grams to moles. How many moles of KNO3 are in
235.06 grams of KNO3?
Answer:
3.17648
Explanation:
K = 19
N = 7
O3 = 48
19 + 7 + 48 = 74
74 = Mr of KNO3
moles = mass / Mr
moles = 235.06 / 74
moles = 3.17648
name all monatomic and polyatomic ions
What is a 2. 0 molar solution?.
The molar solution 2.0 obtained when 0.5 mole solute is dissolved in:
250 ml solution (Option C)
Moles of solute in moles divided by volume of solution in liters is molarity.
M = n/V
Where:
M denotes molarity
n denotes moles of solute, and
V denotes volume.
You can solve for the number of moles by multiplying the equation by volume, or MV = n.
So, to find the number of moles of solute, multiply the molarity by the volume. The molar mass of the solute can then be used to convert moles of solute into grams of solute, or mass.
Molarity = moles of solute / volume of solution
2 = 0.5 / volume of solution
So, the volume of solution = 0.25 L
= 250 ml
The question is incomplete, it should be:
2.0 molar solution is obtained when 0.5 mole solute is dissolved in:
A. 250 ml solvent
B. 250 gr solvent
C. 250 ml solution
D. 1000 ml solvent
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in complementary base pairing bonds with and bonds with
The two strands of DNA are held together by hydrogen bonds.
What is chemical bond?A chemical bond is an attraction between two atoms or ions that allows the formation of chemical substances. Chemical bonds are formed when the atoms share or transfer electrons in order to obtain a full outer shell of electrons, achieving a more stable electron configuration. This can happen through covalent bonds, ionic bonds, hydrogen bonds, and other types of bonds. Chemical bonds are responsible for the stability of molecules and are responsible for many of the physical and chemical properties of substances.
These hydrogen bonds form between the nitrogenous bases of the two strands of DNA. Adenine (A) on one strand always bonds with thymine (T) on the other, and cytosine (C) always bonds with guanine (G). This highly specific arrangement of base pairs is essential for the replication and transcription of genetic information.
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If you walk at a speed of 3 meters per second (m/s), how far will you walk in 11 seconds?
If you answer please show how you did it too because my teacher is very specific on showing our work!!
If one walks at a speed of 3 meters per second, the distance that will be walked in 11 seconds is 33 metres.
How to calculate distance?Speed is the rate of motion or action, specifically the magnitude of the velocity i.e. it is the rate distance is traversed in a given time.
The speed can be measured by dividing the distance moved by the time taken as follows:
Speed = distance/time
3m/s = d/11
distance = 33metres
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How many moles of water molecules are in 0.100 mol of copper(II) sulphate pentahydrate?
Answer:
0.500 moles of water molecules
Explanation:
The chemical formula of copper(II) sulphate pentahydrate is CuSO4·5H2O, which means that it contains 5 moles of water molecules for every 1 mole of copper(II) sulphate. To find the number of moles of water molecules in 0.100 mol of copper(II) sulphate pentahydrate, we can multiply the number of moles of copper(II) sulphate by the coefficient of water molecules:
0.100 mol x 5 moles of water/1 mole of copper(II) sulphate = 0.500 moles of water.
so there are 0.500 moles of water molecules in 0.100 mol of copper(II) sulphate pentahydrate.
How do you find the velocity of a ball?.
The velocity of the ball is calculated by the formula v = Δs/Δt.
that is [tex]\overline{v}={\frac{\Delta x}{\Delta t}}[/tex]
Velocity is the direction at which an object is moving and serves as a measure of the rate at which its position is changing as seen from a specific point of view and as measured by a specific unit of time (for example, 60 km/h northbound). In kinematics, the area of classical mechanics that deals with the motion of bodies, velocity is a fundamental idea.
A physical vector quantity called velocity must have both a magnitude and a direction in order to be defined. Speed is the scalar absolute value (magnitude) of velocity; it is a coherent derived unit whose quantity is measured in metres per second (m/s or m/s1) in the SI (metric system). In contrast to "5 metres per second east," which is a vector, "5 metres per second," for instance, is a scalar.
By dividing the distance by the time, the ball's speed is determined. The average speed will be 60/3, or 20 feet per second (6.1 metres per second), if the time was 3 seconds.
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How many molecules are in 1. 5 moles?.
There are 9.033 x10²³ molecules in 1. 5 mol
By multiplying the sum of moles by the Avogadro constant, one can get the total number of atoms or molecules in a sample. The equation reads as follows:
number of molecule= moles x avogadro's number
One mole of material has 6.022x10² atoms, and equal quantities of different gases measured at the same pressure and temperature have the same number of molecules in them.
number of molecule= moles x avogadro's number
number of molecule= 1. 5 mol x 6.022x10²³
number of molecule= 9.033 x10²³
Therefore, there are 9.033 x10²³ molecules in 1. 5 mol of H₂O
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Which of the following best explains the relationship between structures X and Y?
The relationship between structures X and Y is X, nuclei, are located inside Y, chromosomes, and these structures provide energy for the cell.
What are chromosomes?A chromosome is a lengthy DNA molecule that contains all or a portion of the genetic code for an organism. The histones, which are the most significant of these proteins in eukaryotic cells, coat the very long, thin DNA fibers in most chromosomes. KROH-muh-some) A structure that can be discovered in a cell's nucleus. DNA and proteins arranged into genes make up a chromosome. 23 pairs of chromosomes are typically present in each cell.The Latin term for a fruit's seed is nucleus (plural: nuclei). The exceedingly dense center part of an atom, or the atomic nucleus, is what it most frequently refers to. The majority of the DNA in a eukaryotic cell is found in the cell nucleus, which is the cell's main organelle.The complete question is,
Which of the following best explains the relationship between structures X and Y?
X, chromosomes, are located inside Y, the nucleus, and these structures store genetic material for the cell.
X, ribosomes, are located inside Y, the nucleus, and these structures provide protection for the cell.
X, nuclei, are located inside Y, chromosomes, and these structures provide energy for the cell.
X, chromosomes, are located inside Y, DNA, and these structures store proteins for the cell.
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What are pollutant that caue acid precipitation to enter the air?
Select the following:
1. Drilling for natural ga
2. Burning coal
3. Tranporting petroleum
Burning coal cause acid precipitation to enter the air.
About Acid rainAcid rain is defined as all kinds of rain with a pH below 5.6. Rain is naturally acidic (pH slightly below 6) because carbon dioxide (CO2) in the air which dissolves with rainwater has the form a weak acid . This type of acid in rain is very useful because it helps dissolve the minerals in the soil which are needed by plants and animals.
Acid rain is caused by Sulfur which is an impurity in fossil fuels as well as nitrogen in the air which reacts with oxygen to form sulfur dioxide and nitrogen oxides. These substances diffuse into the atmosphere and react with water to form sulfuric acid and nitric acid which are easily soluble so that they fall with the rainwater. This acidic rainwater will increase the acidity of the soil and surface water which will prove harmful to fish and plant life. Efforts to overcome this are currently being intensively implemented.
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consider the steps involved in preparing a dilute solution from a stock solution. arrange them in order from first to last.dd deionized water until the volume reaches the mark on the flask.Add the desired amount of stock solution. Obtain a flask that is thoroughly cleaned and dried.Cap the flask and invert several times to thoroughly mix the solution
Obtain a flask that is thoroughly cleaned and dried. Cap the flask and invert several times to thoroughly mix the solution are listed below.
What is volume ?
Volume, a three-dimensional quantity, is used to calculate the capacity of a solid shape. In order to calculate how much space a closed figure can occupy in three dimensions, volume is utilized. An example would be the space or shape that a substance, such as a solid, liquid, gas, or plasma, occupies. In addition, the cubic meter deriving from the S.I. is widely employed to quantify volume.
What is deionized water ?
Demineralized water, also known as DI water or DM water, is occasionally used interchangeably with DEI water. Most of the ions are no longer present in the water. Ions are atoms or molecules that are either positive ions (which are called cations) or negative ions (which are called anions) depending on the ratio of electrons to protons (called a cation).
Steps in preparation of dilute solution from a stock solution
1 Obtain a flask that is thoroughly cleaned and dried
2 Add the desired amount of stock solution
3 Add deionized water until the volume reaches the mark on the flask
4 Cap the flask and invert serval times to thoroughly mix the solution
If a student accidentally adds deionized water past the calibration mark on a volumetric flask she should start over and make an entirely new solution. Because it is calibrated for the particular volume if excess deionized water is added it gives wrong values(errors) in titration.
Therefore, Obtain a flask that is thoroughly cleaned and dried. Cap the flask and invert several times to thoroughly mix the solution are listed above.
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How many atoms are in 2 H2O molecules?.
There are a total of 6 atoms in 2 H2O molecules. Each H2O molecule is made up of 2 hydrogen atoms and 1 oxygen atom, which means that 2 H2O molecules contain a total of 4 hydrogen atoms and 2 oxygen atoms. This can be calculated by multiplying the number of atoms in each molecule (2 hydrogen atoms and 1 oxygen atom) by the number of molecules (2). Therefore, 2 H2O molecules contain 2 x 2 = 4 hydrogen atoms and 2 x 1 = 2 oxygen atoms, for a total of 4 + 2 = 6 atoms.
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What kind of reaction occur in an electrolytic cell? what characterize it voltage?
An electrolytic cell is a type of electrochemical cell that uses an externally applied voltage to drive a chemical reaction.
In an electrolytic cell, the applied voltage causes a reaction to occur, such as the oxidation or reduction of ions in the electrolyte or the decomposition of the material.
The voltage applied across the cell is known as the electrolytic voltage and is typically much higher than the cell's thermodynamic equilibrium voltage.
The electrolytic voltage is used to drive the reaction, and is typically provided by a battery, fuel cell, or other external power source.
The reaction that occurs during an electrolytic cell is characterized by its voltage, current, and power output.
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Is CH3 nonpolar covalent?.
Methane creates a covalent bond that is non-polar. This is due to the fact that there is almost any distinction between the electronegativity of carbon and hydrogen.
Because the electronegativities of the C and H are comparable when we simply consider CH₃, we declare it to be non-polar. As a result, they cancel one another, making CH₃ non-polar.
A methyl anion, the [CH₃-] group, has covalent connections between its carbon and hydrogen atoms. Although a C-H bond has no bond polarity, the anion has molecular polarity because of the negative charge attached to carbon.
Methane creates a covalent bond that is non-polar.
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Which manufacturing process is shown in the photograph?
A. Combining
B. Forming
C. Separating
D. Conditioning
Answer:
looks like separating
Explanation:
cutting the fabric with scissors
Write a bond-line formula for each of the following compounds:
(a) 1,4-Dichloropentane
(b) sec-Butyl bromide
(c) 4-Isopropylheptane (k) 1,4-Dicyclopropylhexane
(d) 2,2,3- Trimethylpentane (I) Neopentyl alcohol
(e) 3-Ethyl-2 methylhexane
(f) Dichlorocyclopentane
(g) cis-1,2 Dimethylcyclopropane
(h) trans-1,2 Dimethylcyclopropane
(i) 4-Methyl-2-pentanol G) trans-4 Isobutyleyclohexanol (m) Bicyclo[2. 2. 2Joctane (n) Bicycl0butane (o) Cyclopentylcyclopentane (p) 7-Methyl bicyclo[2. 2. 1]heptane
Bond line shows a molecular formula with a single line for each of the covalent links.
Define Bond line
Organic chemists have a convention for displaying molecular structures called bond line notation. This represents a bond between two atoms as a line. The ends of the line represent the positions of the bonded atoms. Only atoms other than carbon and hydrogen are particularly shown.
Pentane is the alkane's parent name for 1,4-dichloropentane. The prefix di- indicates that there are two substituents, and the numbers 1 and 4 indicate that they are on the corresponding carbons. Butane serves as the parent chain for sec-butyl bromide. Heptane serves as the parent chain for 4-isopropylheptane. Pentane serves as the parent chain for 2,2,3-trimethylpentane. Hexane serves as the parent chain for 3-Ethyl-2-methylhexane. Cyclopentane serves as the parent chain for dichlorocyclopentane.
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what is the similarities of comets and asteroids
Please help me!!!!!!!
You can apply the straightforward formula to determine the average atomic mass.
How can I determine the average atomic mass of isotopes?You can apply the straightforward formula to determine the average atomic mass.AM = f1 m1 + f2 m2 +... + fn mn.AM stands for average atomic mass, fn for natural abundance of isotope number n, and mn for isotope number n's atomic mass.Add the atomic masses of each isotope to the natural abundance.Add up all the items you got in step one.The resulting value is the element's average atomic mass.The existence of isotopes for elements can be explained by their average atomic mass. It provides us with the average atomic masses of all the element's isotopes.It is advantageous since its value is equal to the molar mass of an element. Additionally, being aware of the tooth.To learn more about average atomic mass refer to:
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A donut has a density of 0.75 g/cm cubed and a mass of 100.0g. What is the volume of the donut?
Answer:
133.333333333 cm^3
Explanation:
Volume = Mass/Density
What is soil conservation and water conservation?
Soil and water conservation are those activities at the local level which maintain or enhance the productive capacity of the land including soil, water and vegetation in areas prone to degradation. prevention or reduction of soil erosion, compaction, salinity; conservation or drainage of water and.
What do you mean by conservation of water?
Water conservation includes all policies, strategies and activities for the sustainable management of natural freshwater resources, for the protection of the hydrosphere and for meeting current and future human demand. The amount of water used affects population, household size, growth and well-being.To know more about conservation of water, click the link given below:
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Predict the polarity of 6 real molecules (O2, HF, H2O, NH3, CF4, CH3F). First, draw the
molecules and any bond dipoles. Then draw any molecular dipoles. Explain your
reasoning before you check your predictions with the simulation.
Carbon dioxide,Ammonia,Oxygen,Water,Hydrogen fluoride,Nitrogen are the polarity of 6 real molecules
What are the molecular polarity?Polar molecules are those that possess regions of positive and negative charge. Water is an example of a polar material. The type of bonds it has, when coupled with its shape, gives one end of the molecule a slight positive charge (the hydrogen end) and the other a slight negative charge (the oxygen end).Like bonds, molecules can also be polar. In a polar molecule, electron density is unevenly distributed throughout the molecule, resulting in regions of partial negative charge and regions of partial positive charge.Whether a molecule is polar or nonpolar is a matter of its geometry. If one end of the molecule has a positive charge while the other end has a negative charge, the molecule is polar. If a charge is evenly distributed around a central atom, the molecule is nonpolar.To learn more about molecular polarity refers to:
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if 2Na + Cl2 --> 2NaCL ... what happened to the two on Cl? and if 2H2O --> 2H2 + O2 what happened to the 2 on the O as well? could you please answer this in like sort of a simple way? my brain is mush at the moment lol.
Explanation:
when a big number is behind a compound, it means there is 2 of it.
for example 2Na would mean there is a sodium atom and another sodium atom not joined together, but they're just near.
when there is a 2 (which should be small and at the bottom) after an atom, it means there are 2 of that atom.
i hope this helps
