Is c o polar or nonpolar. Learning Outcomes Define electronegativity.

Is c o polar or nonpolar 35 units between the bonded atoms. The Lewis structure of carbon monoxide (CO) is O=C with two lone pairs on oxygen and one lone pair on carbon. And we also have to check the molecular geometry of C2H5OH. Perfect for chemistry enthusiasts and students seeking clarity on this essential topic. Is CO polar or nonpolar ?Question = Is CO polar or nonpolar ? Answer = CO ( Carbon monoxide ) is Polar What is polar and non-polar? Polar "In chemistry, polarity is a separation of electric charge leading to a molecule or its chemical groups having an electric dipole or multipole moment. The carbon atom is present at the center of the molecular ion, while all three oxygen atoms occupy the terminal positions, one on each side, making a symmetrical trigonal planar molecular shape and geometry. (You may need to draw Lewis structures and geometric sketches to do so. So I thought the lesson was that polar groups may not have much of an effect on the big nonpolar aromatic EXAMPLE – Predicting Molecular Polarity: Decide whether the molecules represented by the following formulas are polar or nonpolar. Acetic acid (CH3COOH) is the main component of vinegar. 20) atoms. Step #2: Check the bond polarity and molecular geometry The chemical bonds can be Jun 12, 2025 · Is CO32- polar or non-polar? Carbonate (CO32-) is a non-polar molecular ion. In the most stable Lewis representation of CO, -1 and +1 formal charges are present on the adjacent carbon and oxygen atoms, respectively. To determine if a molecule is polar or nonpolar by considering it’s Lewis structure, molecular geometry and bond polarity. Step #2: Check the bond polarity and molecular geometry The chemical bonds can be either nonpolar, polar or ionic depending on the Jun 12, 2025 · Nitric oxide (NO) is a weakly polar molecule. The carbon and oxygen atom have unequal charge distribution and therefore CO bond has a net dipole moment making CO a polar molecule. Even though the C-O bond is polar, the symmetrical shape of the molecule makes it nonpolar as it has no net dipole. O - C - O The oxygen atoms have a delta- charge, and the carbon a delta+ charge. But why? And how can you say that CF2Cl2 is a polar molecule? Want to know the reason? Let’s dive into it! CF2Cl2 (or CCl2F2) is a POLAR molecule because the C-F bonds and C-Cl bonds present in the molecule are polar and it has asymmetric geometry which causes the partial positive (ẟ+) and partial negative (ẟ-) charge to appear on the molecule. Jul 9, 2025 · In this article, we will study Formaldehyde (CH2O) lewis structure, molecular geometry, shape, bond angle, hybridization, polar or nonpolar, etc. Jan 8, 2021 · And such formation of partial charges leads to the polarity in the molecule. May 30, 2024 · It is not considered as polar or nonpolar since ionic compounds do not have distinct polar or nonpolar characteristics as covalent compounds do. Although C and S have very similar electronegativity values, S is slightly more electronegative than C, and so the C-S bond is just slightly polar. And we also have to check the molecular geometry of CHCl3. In this molecule, the oxygen side is more negative than the sulfur side. CCl 4 d. And we also have to check the molecular geometry of CH3OH. The C–O bond is considerably polar. Jan 19, 2025 · Carbon monoxide (CO) is widely known as a gas component in the Earth's atmosphere and industrial processes. What is the electronegativity of an atom. 89 difference in Notice that a tetrahedral molecule such as CCl A 4 is nonpolar Figure (4 12 1. The C-C bond present in CH 3 COOH is purely non-polar, the C-H bonds are very weakly polar owing to an electronegativity difference of 0. Covalent bonds can be polar or nonpolar, depending on the electronegativity difference between the atoms involved. Nonpolar compounds will be symmetric, meaning all of the sides around the central atom are identical - bonded to the same element with no unshared pairs of electrons. Oct 30, 2024 · Is CHCl3 polar or nonpolar? The C-Cl bonds are polar due to the electronegativity difference between carbon and chlorine. an F–F bond an S–N bond an I–Cl bond Arrange the following bonds from least polar to most polar: C-N, C-O, C-C, C-H, N-H, O-H Solutions Electronegativity is a qualitative measure of how much an atom attracts electrons in a covalent bond. It consists of one oxygen (O) atom, one carbon (C) atom, and one sulfur (S) atom. Describe the electronegativity difference between each pair of atoms and the resulting polarity (or In this video we explore the unique dipole moment of carbon monoxide, which seems to defy expectations about how polar a carbon-oxygen triple bond is. Apr 13, 2020 · Learn whether CO is polar or nonpolar and the underlying reasoning behind this determination. I'm having a bit of trouble deciding when a molecule is polar (hydrophilic) or nonpolar (hydrophobic) if it has aromatic rings attached to polar functional groups. Nonpolar Bonds A covalent bond can have a range of polarities. Learn how polarity impacts solubility, intermolecular forces, and chemical behavior, with clear examples and explanations to enhance your understanding of this fundamental chemistry concept. The carbon atom is present at the center of the molecule, while oxygen and sulfur atoms occupy terminal positions, one on each side, making a linear molecular shape. Now in the next step we have to check whether these two C-H bonds and one C=O bond are polar or nonpolar. To understand this concept, the polarity of a molecule is analyzed based on its atomic structure, electronegativity, and molecular Electronegativity is a measure of the relative attraction for the pair of electrons in a bond. May 24, 2023 · CO2 (or Carbon dioxide) is a NONPOLAR molecule because both the bonds (C=O bonds) are identical and CO2 has symmetrical geometry which cancels out the bond polarity. Polar bonds form between any two dissimilar atoms that have different electronegativity values. Notice that a tetrahedral molecule such as CCl A 4 is nonpolar Figure (4 12 1. The Lewis structure for CO 2 is The electronegativities of carbon and oxygen are 2. Polar molecules tend to dissolve in polar solvents due to the attraction between opposite charges, while nonpolar molecules dissolve in nonpolar solvents. No, CO 2 is not polar, even though the bonds are polar. Jun 24, 2022 · Carbon Monoxide is a diatomic molecule, the partial negative charge exists on the carbon and partial positive charge exists on the oxygen atom. These ẟ+ and This quiz helps you practice determining polarity and calculating electronegativity differences in a variety of chemical bonds. Jun 12, 2025 · Are lipids polar or non-polar? Lipids are essentially non-polar in nature due to the presence of long hydrophobic hydrocarbon chains in their structures. Electronegativity is a measure of the tendency of an atom to attract electrons (or electron density) towards itself. A CH3COOH molecule is composed of two C-atoms, two O-atoms and four H-atoms. May 24, 2023 · CH3OH (Methanol) is a POLAR molecule. Describe how molecular geometry plays a role in determining whether a molecule is polar or nonpolar. 44. However, there is a large electronegativity difference CH3Cl Polar or Nonpolar? The C-Cl bond is polar, and the unsymmetrical shape of the molecule makes it polar as it has a net molecular dipole. e. Hence, an ethanol (C2H5OH) molecule is polar and has a high net dipole moment value (net µ > 0). BF 3 is a trigonal planar molecule and all three peripheral atoms are the same. OF 2 c. Thus, the two bonds do not have of the same bond dipole moment, and the bond moments do not cancel. Jun 12, 2025 · So, to learn whether NaCl is polar or non-polar and the reason behind it, you have to do just one thing, i. 8 D). Now in the next step we have to check whether these four C-Cl bonds are polar or nonpolar. So let’s begin! Is C-H bond polar or non-polar? CH2O Polar or Nonpolar? The C-O bond is polar, and the unsymmetrical shape of the molecule makes it polar as it has a net molecular dipole. May 25, 2023 · So from the above diagram we have come to know that the COCl2 molecule has one C=O bond and two C-Cl bonds. May 8, 2023 · Is CCl 4 Polar or Nonpolar? CCl4 is a nonpolar molecule, despite having four polar C–Cl bonds. 24 units exists between the covalently bonded oxygen and hydrogen atoms. HCN Solution: a. Notice that a tetrahedral molecule such as CCl A 4 is nonpolar (Figure 5 12 1). 9 (polar covalent), and 2. , dimethyl ether (CH3OCH3), also possesses a bent or V-shape w. The carbon atom is kept at the central position, and the other atoms are at the surrounding positions, making a trigonal planar molecular shape. Now in the next step we have to check whether these bonds are polar or nonpolar. , a carbon (C) atom in the center is bonded to 2 hydrogens (H) atoms and an oxygen (O) atom by single and double covalent bonds respectively. But looking at the difference in the electronegativities and polarisation in this molecule, we can say that Carbon Monoxide is a polar molecule. Polar vs. Another non polar molecule shown below is boron trifluoride, BF 3. Because oxygen is more electronegative than sulfur, the oxygen end of the molecule is the negative end. In this article, we will discuss whether the C-H bond is polar or non-polar, a question that often confuses many chemistry students. Jul 29, 2021 · To find out whether Ethanol is a polar or nonpolar molecule we look at its Lewis Structure, Bond Nature and other properties. Learn to determine if CO (Carbon monoxide) is polar or non-polar based on the Lewis Structure and the molecular geometry (shape). Nov 14, 2024 · Is urea polar or nonpolar? Urea (CH₄N₂O) features polar C=O and N-H bonds. There is a small electronegativity difference between a C and an H atom in a C-H bond. Step #2: Check whether individual bonds are polar or nonpolar The chemical bonds can be either nonpolar, polar or ionic depending on the difference of the electronegativity values (ΔEN) between the two atoms. Step #2: Check the bond polarity and molecular geometry The chemical bonds can be either nonpolar, polar or ionic depending on May 24, 2023 · So from the above diagram we have come to know that the CH2O molecule has two C-H bonds and one C=O bond. For example, I thought warfarin (image below) was polar because of the 2 C=O bonds and the OH. May 24, 2023 · So from the above diagram we have come to know that the CH2O molecule has two C-H bonds and one C=O bond. Happy learning! Is NaCl polar or non-polar? Sodium chloride (NaCl) is polar in nature. Aug 28, 2015 · The reason why carbon monoxide is often referred to a being practically nonpolar is because of its very small dipole moment. In short, the CO molecule forms a pole of positive charge and negative charge on it. Maybe you’ve heard that water is a polar molecule, yet what about carbon dioxide? Is it polar or nonpolar? Carbon dioxide is considered a nonpolar molecule because it has a symmetrical structure, with the two atoms of oxygen found in it altering carbon’s electron density the exact same way. Jan 8, 2022 · Carbon dioxide is composed of two C-O polar bonds; however, the molecule is nonpolar as the bonds are arranged in a way that the net dipole is zero. When all the dipoles for all the covalent bonds that make up a molecule are added together as vectors, the result is the net dipole moment of the entire molecule. Step #2: Check the bond polarity and molecular geometry The chemical bonds can be either nonpolar, polar or ionic depending on the difference of May 24, 2023 · So from the above diagram we have come to know that the CCl4 molecule has four C-Cl bonds. Covalent bonds can be nonpolar or polar, depending on the electronegativities of the atoms involved. CS2 Polar or Nonpolar? The C-S bond is nonpolar and the symmetrical shape of the molecule makes it nonpolar as it has no net dipole. The strong O-H dipole moments do not get canceled with the small C-H dipole moments due to the bent, angular or V-shape of an alcohol Jun 16, 2023 · So from the above diagram we have come to know that the CHCl3 molecule has one C-H bond and three C-Cl bonds. To determine if a molecule is polar or nonpolar, it is frequently useful to look at Lewis structures. It is an ionic compound composed of oppositely charged sodium (Na +) and chloride (Cl –) ions, tightly held together by strong electrostatic forces of attraction . Each of the C-O bonds has a dipole moment of 2. May 25, 2023 · So from the above diagram we have come to know that the OCS molecule has one Carbon-Oxygen bond and one Carbon-Sulfur bond. The chemical bonds can be either nonpolar, polar or ionic depending on the difference of the electronegativity values (ΔEN) between the two atoms. 44) and hydrogen (E. Jun 12, 2025 · Is OCS polar or non-polar? Carbonyl sulfide (COS or OCS) is a polar molecule. It consists of one carbon (C) atom, one oxygen (O) atom, and two chlorine (Cl) atoms. Chloromethane, CH 3 Cl, is another example of a polar May 24, 2023 · Now in the next step we have to check whether these C-H bonds, C-C bond, C-O bond and O-H bond are polar or nonpolar. This disparity creates a dipole moment, making the bond polar. So from the above diagram we have come to know that the C3H8O molecule has C-H bonds, C-C bond, C-O bond and O-H bond. Oct 19, 2023 · Carbon dioxide (CO2) is nonpolar because it has a linear, symmetrical structure, with 2 oxygen atoms of equal electronegativity pulling the electron density from carbon at an angle of 180 degrees from either direction. Its Lewis structure shows a triple bond between C and O, with one lone pair on oxygen. 4 units between the bonded atoms. 1 (ionic), respectively. Have a look at the above image. The molecular geometry is tetrahedral, leading to a net dipole moment, making CHCl3 polar. POLARITY IN ORGANIC MOLECULES Every covalent bond is either polar or nonpolar. Now in the next step we have to check whether the C-H bond and C-Cl bonds are polar or nonpolar. Polar molecules must contain polar bonds due to a difference in electronegativity between the bonded atoms The polarity of molecules based on polar bonds and vector addition of the polarity vectors of the bonds in a molecule are described. The insolubility of lipids or oil in polar molecules such as water further endorses the non-polarity of the latter. A hydrocarbon chain consists of numerous C-H bonds. These electronic exchange between carbon and oxygen atoms make the CO a polar molecule. CH 2 Cl 2 e. Oxygen is more electronegative than carbon, so there is a polarity in the CO molecule. So from the above diagram we have come to know that the CH3OH molecule has C-H bonds, C-O bond and O-H bond. May 25, 2023 · So from the above diagram we have come to know that the CO3 2- ion has two C-O bonds and one C=O bond. 3D, but the dipoles act in opposite directions, resulting in the net-zero dipole. Nov 13, 2024 · Is caffeine polar or nonpolar? Caffeine is polar due to the presence of multiple nitrogen and oxygen atoms, which create polar bonds, and its unsymmetrical structure contributes to a net molecular dipole, enhancing its polarity. May 25, 2023 · CF2Cl2 is a POLAR molecule. Now in the next step we have to check whether these C-H bonds, C-O bond and O-H bond are polar or nonpolar. CO is practically non-polar since the σ-electron drift from C to O is almost nullified by the π -electron drift from O to C. The formation of covalent bonds is … Covalent bonds can be nonpolar or polar, depending on the electronegativities of the atoms involved. Jun 12, 2025 · Is CH2O polar or non-polar? Formaldehyde (CH2O) is a polar molecule. The CO bond in carbon monoxide is polar. The individual dipole moments of each C–Cl bond cancel each other out vectorially, resulting in no net dipole moment. Feb 2, 2025 · Discover the key differences between co polar and nonpolar molecules, exploring their molecular structure, electronegativity, and bonding characteristics. Mar 31, 2023 · CO is a polar molecule because it has a partial positive charge (ẟ+) on the Carbon atom and partial negative charge (ẟ-) on the Oxygen atom. The C-C bonds are non-polar, while the C-H bonds present in alcohols are weakly polar. C-Se, C-O, and N-H are polar, while Cl-Cl, O=O, are non-polar because they have identical bonded atoms. C-H is non-polar because the have negligible difference in electronegativity. This molecule is also linear, but the C=O and C=S bonds are not equally polar, because O is more electronegative than S. An electronegativity difference of 0. One common form of polar interaction is the hydrogen bond, which is also known as the H-bond. On one end of the spectrum is the purely nonpolar bond in which electrons are shared equally among bonded atoms. r. Each C-H bond is weakly polar due to an electronegativity difference of only 0. Jan 9, 2020 · Is the molecule CO carbon monoxide polar or non-polar? CO (Carbon monoxide) is polar in nature because of the difference in electronegativity of carbon (2. Nov 4, 2024 · Is co polar or nonpolar? The CO molecule is polar due to the difference in electronegativity between carbon and oxygen, creating a dipole moment. Oct 8, 2024 · Discover the definitive answer to Is Carbon Monoxide Polar or Nonpolar? in this insightful article. Some polar character may be present in a May 21, 2021 · Is the CO32- ion polar in nature? Find out in this article detailing its molecular shape and dipole moment to determine its polarity. This tool is useful for chemistry students and professionals to understand electron sharing behavior in molecules and the tendency of atoms to attract electrons. When its value is zero, the molecule is said to be nonpolar, otherwise it’s said to be polar. Check out a few examples with diagrams. The absolute values of the electronegativity differences between the atoms in the bonds H H, H Cl, and Na Cl are 0 (nonpolar), 0. Figure 4 12 1 Some examples of nonpolar molecules based on molecular geometry (BF 3 and CCl 4). 55) and oxygen (3. 03 units exists between a carbon The Big Idea In this lesson, you'll learn how to use bond polarity, Lewis structures, and molecular geometry to determine if a molecule is polar or nonpolar. N = 2. Jun 12, 2025 · The polarity of a sugar molecule is accredited to the presence of strongly polar hydroxyl (OH) functional groups as well as the presence of a polar glycosidic (C-O-C) linkage in it. Dec 15, 2020 · Is CO2 polar or nonpolar? Want to know the answer to this question? If yes, then read this detailed blog on CO2 polarity and get in-depth information about the molecule’s polarity. Sodium transfers an ele Why CO is a nonpolar molecule? Due to the presence of pi bond in \ [CO\] molecule, electrons are drifted from oxygen towards carbon thus nullifying the polarity and making the molecule non-polar. The formation of covalent bonds is … H2O Polar or Nonpolar? The O-H bond is polar, and the unsymmetrical shape of the molecule makes it polar as it has a net molecular dipole. This is due to its highly symmetrical tetrahedral shape. 55 and chlorine at 3. And we also have to check the molecular geometry of OCS. Calculate the molecular polarity (polar, non-polar) of a chemical bond based on the electronegativity of the elements. The 0. Obviously, it is possible to have nonpolar molecules made May 24, 2023 · But wait, let me give you some detailed information about the nonpolar nature of O2 molecule. N = 3. When the difference is very small or zero, the bond is covalent and nonpolar. Draw Lewis structures, name shapes and indicate polar or non-polar for the following molecules: CH4 Jun 12, 2025 · Is COCl2 polar or non-polar? Phosgene (COCl2) is a polar molecule. 11~\mathrm {D} && \text {Direction:}~\longleftarrow\hspace {-1ex}+ \end {align} Unfortunately the explanation of the bonding in carbon monoxide is far from simple, and it is perfectly On the other hand, OCS is a polar molecule. Polarity in a molecule occurs due to the unequal sharing Jul 9, 2025 · In this tutorial, we will discuss H2CO lewis structure, molecular geometry, shape, polar or nonpolar, bond angle, hybridization, etc. Step #2: Check the bond polarity and molecular geometry The chemical bonds can be either nonpolar Although the C–O bond is polar, C and S have the same electronegativity values as shown in Figure 15, so there is no C–S dipole. Each O-H bond is polar as an electronegativity difference of 1. Read this blog post to know if this molecule is polar or not. And we also have to check the molecular geometry of COCl2. Now in the next step we have to check whether these C-H bonds, C-C bond, C-O bond and O-H bond are polar or nonpolar. Now in the next step we have to check whether the Carbon-Oxygen bond and Carbon-Sulfur bond are polar or nonpolar. Jul 19, 2023 · VSEPR theory predicts a linear molecule: The C-O bond is considerably polar. And we also have to check the molecular geometry of C3H6O. Explore the molecular structure of CO, its bond polarity, and how it differs from nonpolar molecules. Jun 1, 2024 · Is CO a ionic polar covalent or non polar covalent bond? It is a non-polar covalent bond. May 7, 2020 · Nonpolar bonds form between two nonmetals with the same electronegativity value. \begin {align} \ce { {}^ {\ominus}\!:C#O:^ {\oplus}} && \text {Dipole:}~|\mathbf {q}|=0. Covalent bonds can be broken if energy is added to a molecule. It consists of one carbon (C) atom and three oxygen (O) atoms. Learn about electronegativity, dipole moments, and why carbon monoxide exhibits unique chemical properties. It is made up of three different atoms i. Oct 30, 2024 · Is CH2O polar or nonpolar? The C=O bond is polar due to oxygen's higher electronegativity, and the bent shape of the molecule results in an overall dipole moment, making CH2O polar. Polar bonds form between atoms of elements with different electronegativity values. The bond in sodium chloride, for instance, is ionic. t the central O-atom. Key Factors Determining Polarity: Sep 16, 2023 · The strong C-O and O-H dipole moments stay uncancelled in the overall molecular shape. Additionally, polar molecules may exhibit stronger intermolecular forces, influencing their boiling points and Whether a bond is nonpolar or polar covalent is determined by a property of the bonding atoms called electronegativity. Mar 31, 2023 · Here is a skeleton of C3H8O lewis structure and it contains C-H bonds, C-O bond, C-C bond and O-H bond. … Boiling point When comparing a polar and nonpolar molecule with similar molar masses, the polar molecule in general has a higher boiling point, because the dipole–dipole interaction between polar molecules results in stronger intermolecular attractions. Chemical Bond Polarity Calculator helps determine whether a covalent bond between two atoms is polar or non-polar. Mar 31, 2023 · But wait, let me give you some detailed information about the polarity of OH- ion. Water is also polar, but for a different reason. May 24, 2024 · The polarity of a molecule affects its physical and chemical properties, including solubility, boiling point, and reactivity. Nov 20, 2024 · Is the C-Cl bond polar or nonpolar? The C-Cl bond is polar due to the difference in electronegativity, with carbon at 2. It has various properties and behaviors that have been studied, and one of the key questions that arise is whether carbon monoxide is a polar molecule. Because of the linear symmetry of the molecule, the negative charges around the oxygen atoms cancel out. Distinguish between the following three types of Describe and explain a nonpolar covalent bond. 16. Molecules as a whole can also be described as nonpolar or polar, depending on the symmetry of the … Covalent bonds between different atoms have different bond lengths. , continue reading this article. 55 and 3. Table of Contents Is CH 2 O Polar or Nonpolar? Electronegativity of CH 2 O How to Check Polarity of a Molecule? Frequently Asked Questions – FAQs Is CH 2 O Polar or Nonpolar? The difference in electronegativity and electron sharing between two atoms in a covalent bond determines whether the molecule is polar or non-polar. Step #2: Check whether individual bonds are polar or nonpolar The chemical bonds can be either nonpolar, polar or ionic depending on the difference Up to this point, we’ve treated chemical bonds as either ionic or covalent. And we also have to check the molecular geometry of CH2O. Jun 12, 2025 · Is vinegar polar or non-polar? Vinegar is polar. ) a. It uses the difference in electronegativity values to identify the type of bond formed. Jun 12, 2025 · The electronegativity difference between two bonded atoms governs the polarity of a chemical covalent bond. When it is large, the bond is polar covalent or ionic. Its asymmetric structure creates a net dipole, making urea a polar molecule with significant solubility in water. Step #2: Check the bond polarity and molecular geometry The chemical bonds can be either nonpolar, polar or ionic depending on May 24, 2023 · So from the above diagram we have come to know that the C3H6O molecule has C-H bonds, C-C bonds and C=O bond. 24 units between the covalently bonded oxygen (E. Jun 12, 2025 · Contrarily, there is some effect of the C-O and C=O dipole moments; however, it gets negated in comparison to the long non-polar hydrocarbon chain. 35 units between the covalently bonded carbon and hydrogen atoms. Learning Outcomes Define electronegativity. Jul 16, 2015 · Similarly carbon dioxide is a linear molecule so the dipoles of the (fairly polar) C=O bonds point in exactly the opposite direction and so cancel out. 44) atoms. That’s the short answer regarding carbon May 24, 2023 · Now in the next step we have to check whether these three B-Cl bonds are polar or nonpolar. Jun 10, 2025 · CO is a polar molecule (net µ > 0) as the more electronegative O-atom pulls the C ≡ O shared electron cloud away from the C-atom. To determine if the molecule is polar or nonpolar, we look at the electronegativity difference between carbon and oxygen. Water, however is bent so the dipoles of the polar O-H bonds do not cancel out leaving a polar molecule with a significant dipole moment (~1. Describe how the electronegativity difference between two atoms in a covalent bond results in the formation of a nonpolar covalent, polar covalent, or ionic bond. It consists of a polar N=O double bond due to an electronegativity difference of 0. Predict polarity of a molecule. However, some people still believe that the molecule is nonpolar practically. CO 2 b. But it apparently is nonpolar. We begin with a discussion about the effects Jun 12, 2025 · The O-H bond is strongly polar, having an electronegativity difference of 1. Nonpolar molecules may contain any type of chemical bonds, but the partial charges cancel each other out. The other isomer of C 2 H 6 O i. eag azejb cei qjm huczzm falp jhfkrg qorw zugwpd hcczy ouv drapyli xhwxccb fglv eqagbyol