Lab Report On Diatomic Molecules
Description
Did you know that diatomic molecules make up majority of the Earth’s atmosphere? The prefix “di” means ‘’two’’ in Greek, so these diatomic molecules are made up of two atoms. In this lesson, we will discuss diatomic molecules and go over some examples.
!!!What is a Diatomic Molecule?
Diatomic molecules are all around us. The Earth’s atmosphere is mainly composed of about 78% oxygen and 21% nitrogen. The oxygen and nitrogen present in the atmosphere are both in the form of ‘’diatomic molecules’’, as shown below:
The subscript 2 of oxygen and nitrogen indicate the number of oxygen atoms and nitrogen atoms. So the oxygen molecules present in the atmosphere have two oxygen atoms and the nitrogen molecules have two nitrogen atoms. …show more content…
There are also other diatomic molecules that we encounter everyday.
Carbon monoxide (CO) is produced from combustion fumes of cars and trucks, and is made of one carbon (C) atom and one oxygen (O) atom. Hydrochloric acid (HCl) is present in the gastric acid produced by our stomach, and is a common acid that we use in the chemistry lab. It is made of one hydrogen (H) atom and one chlorine (Cl) atom:
__Diatomic molecules__ are molecules that are composed only of ‘’two atoms’’. Diatomic molecules are either ‘’homonuclear’’ or ‘’heteronuclear’’. __Homonuclear diatomic molecules__ are composed of two atoms of the ‘’same element’’, like in the case of oxygen (O2) and nitrogen (N2) shown in the illustration above. __Heteronuclear diatomic molecules__ are composed of two atoms of ‘’different elements’’, like in the case of hydrochloric acid (HCl) and carbon monoxide (CO).
The two atoms in a diatomic molecule are connected in a straight line. The __molecular geometry__, which is what describes the shape, of a diatomic molecule is a ‘’linear geometry’’. Shown below are the __Lewis structures__, which show how atoms are bonded in the molecule and lone pairs of electrons, of the diatomic molecules O2, N2, HCl and CO. The red dots represent the electrons and the lines represent the bonds. We can see here that the diatomic molecules exhibit linear molecular …show more content…
geometry.
!!!Homonuclear Diatomic Molecules
There are seven elements that occur naturally as homonuclear diatomic molecules. All of these molecules are in the gaseous state. Five of these elements occur as diatomic elements at room temperature, which is 25 degrees Celsius. These are hydrogen, nitrogen, oxygen, fluorine and chlorine:
At slightly higher temperatures, iodine and bromine exists as homonuclear diatomic molecules: A useful mnemonic device to remember the seven homonuclear diatomic molecules that exist is: __H__ave __N__o __F__ear __O__f __I__ce __C__old __B__eer:
!!!Heteronuclear Diatomic Molecules
Heteronuclear diatomic molecules consist of two atoms of two different elements. There is an abundance of heteronuclear molecules. Two types of bonding can occur in a heteronuclear diatomic molecule: ionic and covalent. __Ionic bonding__ occurs when a metal bonds with a nonmetal. __Covalent bonding__ occurs when two nonmetals bond together. How do we know if an element is a metal or a nonmetal? We refer to the periodic table:
All elements, except for hydrogen, at the ‘’left’’ side of the stairs are classified as metals and all elements at the ‘’right’’ side of the stairs are classified as nonmetals.
The lanthanides and actinides are also classified as metals.
The following are examples of heteronuclear diatomic molecules with ionic bonding:
Let us take NaCl, for example, sodium (Na) is on the far left side of the periodic table, indicating it is a metal, and chlorine (Cl) is a nonmetal, so NaCl is a heteronuclear diatomic molecule with an ionic bond.
The following are examples of heteronuclear diatomic molecules with covalent bonding:
Let us look at HBr, for example. Hydrogen is on the left side of the stairs that divide metals and nonmetals in the periodic table, but ‘’hydrogen is a nonmetal’’. Bromine (Br) is also a nonmetal, so HBr is a heteronuclear diatomic molecule with a covalent bond.
!!!Lesson Summary
__Diatomic molecules__ consist of two atoms that are either from the same element, or from different elements. If the diatomic molecule consists of atoms of the same element, then this is classified as a __homonuclear diatomic molecule__. If the diatomic molecule consists of atoms from two different elements, then it is a __heteronuclear diatomic
molecule.
There are seven elements that naturally occur as homonuclear diatomic molecules in their gaseous states: hydrogen, nitrogen, oxygen, fluorine, chlorine, bromine and iodine. Bromine and iodine need slightly higher temperatures than room temperature to occur as gaseous diatomic molecules. Heteronuclear diatomic molecules can either have an ionic bond or a covalent bond. An ionic bond occurs in a heteronuclear diatomic molecule when a metal is bonded to a nonmetal. A covalent bond occurs when two nonmetals are bonded together.
Quiz:
1. Which of the following statements are true?
- The elements nitrogen and oxygen are diatomic gases in their natural states.
- Ionic bond occurs when two nonmetals are bonded together
- Covalent bond occurs when a metal and a nonmetal are bonded together
- A diatomic molecule is one that is made of ONLY two different elements.
Explanation: the only true statement is “The elements nitrogen and oxygen are diatomic gases in their natural states.” The rest are false because covalent bonds occur when two nonmetals bond together and an ionic bond is when a metal and a nonmetal is bonded together.
A diatomic molecule on the other hand can be made of two different elements or two atoms of the same element, so this statement is also false.
2. Which does NOT occur as a diatomic molecule?
a. Fluorine c. Bromine
b. Nitrogen d. Boron
Explanation: There are seven elements that naturally occur as homonuclear diatomic molecules n their gaseous states: hydrogen, nitrogen, oxygen, fluorine, chlorine, bromine and iodine. Boron is NOT included in this list.
3. Which of the following are heteronuclear diatomic elements with a covalent bond?
MgO
CaO
HF
BaO
Explanation: MgO, CaO and BaO all have ionic bonds. The elements H and F are both nonmetals, so this is a covalent bond.
4. Which of the following is a homonuclear diatomic molecule that needs a slightly higher temperature than room temperature to exist in its gaseous state?
H2
Br2
ClF
I2
Explanation: H2 and Br2 can occur as gaseous homonuclear diatomic molecules at room temperature. ClF is a heteronuclear diatomic molecule. I2 needs a slightly higher temperature than room temperature to occur as a gaseous diatomic molecule.
5. Which of the following is NOT a diatomic molecule?
PCl3
NaCl
O2
BaO
Explanation: All are diatomic molecules except PCl3. Diatomic molecules are only made of two atoms. PCl3 has one P atom and three Cl atoms. Therefore, this is NOT a diatomic molecule.
Did you know that diatomic molecules make up majority of the Earth’s atmosphere? The prefix “di” means ‘’two’’ in Greek, so these diatomic molecules are made up of two atoms. In this lesson, we will discuss diatomic molecules and go over some examples.
!!!What is a Diatomic Molecule?
Diatomic molecules are all around us. The Earth’s atmosphere is mainly composed of about 78% oxygen and 21% nitrogen. The oxygen and nitrogen present in the atmosphere are both in the form of ‘’diatomic molecules’’, as shown below:
The subscript 2 of oxygen and nitrogen indicate the number of oxygen atoms and nitrogen atoms. So the oxygen molecules present in the atmosphere have two oxygen atoms and the nitrogen molecules have two nitrogen atoms. …show more content…
There are also other diatomic molecules that we encounter everyday.
Carbon monoxide (CO) is produced from combustion fumes of cars and trucks, and is made of one carbon (C) atom and one oxygen (O) atom. Hydrochloric acid (HCl) is present in the gastric acid produced by our stomach, and is a common acid that we use in the chemistry lab. It is made of one hydrogen (H) atom and one chlorine (Cl) atom:
__Diatomic molecules__ are molecules that are composed only of ‘’two atoms’’. Diatomic molecules are either ‘’homonuclear’’ or ‘’heteronuclear’’. __Homonuclear diatomic molecules__ are composed of two atoms of the ‘’same element’’, like in the case of oxygen (O2) and nitrogen (N2) shown in the illustration above. __Heteronuclear diatomic molecules__ are composed of two atoms of ‘’different elements’’, like in the case of hydrochloric acid (HCl) and carbon monoxide (CO).
The two atoms in a diatomic molecule are connected in a straight line. The __molecular geometry__, which is what describes the shape, of a diatomic molecule is a ‘’linear geometry’’. Shown below are the __Lewis structures__, which show how atoms are bonded in the molecule and lone pairs of electrons, of the diatomic molecules O2, N2, HCl and CO. The red dots represent the electrons and the lines represent the bonds. We can see here that the diatomic molecules exhibit linear molecular …show more content…
geometry.
!!!Homonuclear Diatomic Molecules
There are seven elements that occur naturally as homonuclear diatomic molecules. All of these molecules are in the gaseous state. Five of these elements occur as diatomic elements at room temperature, which is 25 degrees Celsius. These are hydrogen, nitrogen, oxygen, fluorine and chlorine:
At slightly higher temperatures, iodine and bromine exists as homonuclear diatomic molecules: A useful mnemonic device to remember the seven homonuclear diatomic molecules that exist is: __H__ave __N__o __F__ear __O__f __I__ce __C__old __B__eer:
!!!Heteronuclear Diatomic Molecules
Heteronuclear diatomic molecules consist of two atoms of two different elements. There is an abundance of heteronuclear molecules. Two types of bonding can occur in a heteronuclear diatomic molecule: ionic and covalent. __Ionic bonding__ occurs when a metal bonds with a nonmetal. __Covalent bonding__ occurs when two nonmetals bond together. How do we know if an element is a metal or a nonmetal? We refer to the periodic table:
All elements, except for hydrogen, at the ‘’left’’ side of the stairs are classified as metals and all elements at the ‘’right’’ side of the stairs are classified as nonmetals.
The lanthanides and actinides are also classified as metals.
The following are examples of heteronuclear diatomic molecules with ionic bonding:
Let us take NaCl, for example, sodium (Na) is on the far left side of the periodic table, indicating it is a metal, and chlorine (Cl) is a nonmetal, so NaCl is a heteronuclear diatomic molecule with an ionic bond.
The following are examples of heteronuclear diatomic molecules with covalent bonding:
Let us look at HBr, for example. Hydrogen is on the left side of the stairs that divide metals and nonmetals in the periodic table, but ‘’hydrogen is a nonmetal’’. Bromine (Br) is also a nonmetal, so HBr is a heteronuclear diatomic molecule with a covalent bond.
!!!Lesson Summary
__Diatomic molecules__ consist of two atoms that are either from the same element, or from different elements. If the diatomic molecule consists of atoms of the same element, then this is classified as a __homonuclear diatomic molecule__. If the diatomic molecule consists of atoms from two different elements, then it is a __heteronuclear diatomic
molecule.
There are seven elements that naturally occur as homonuclear diatomic molecules in their gaseous states: hydrogen, nitrogen, oxygen, fluorine, chlorine, bromine and iodine. Bromine and iodine need slightly higher temperatures than room temperature to occur as gaseous diatomic molecules. Heteronuclear diatomic molecules can either have an ionic bond or a covalent bond. An ionic bond occurs in a heteronuclear diatomic molecule when a metal is bonded to a nonmetal. A covalent bond occurs when two nonmetals are bonded together.
Quiz:
1. Which of the following statements are true?
- The elements nitrogen and oxygen are diatomic gases in their natural states.
- Ionic bond occurs when two nonmetals are bonded together
- Covalent bond occurs when a metal and a nonmetal are bonded together
- A diatomic molecule is one that is made of ONLY two different elements.
Explanation: the only true statement is “The elements nitrogen and oxygen are diatomic gases in their natural states.” The rest are false because covalent bonds occur when two nonmetals bond together and an ionic bond is when a metal and a nonmetal is bonded together.
A diatomic molecule on the other hand can be made of two different elements or two atoms of the same element, so this statement is also false.
2. Which does NOT occur as a diatomic molecule?
a. Fluorine c. Bromine
b. Nitrogen d. Boron
Explanation: There are seven elements that naturally occur as homonuclear diatomic molecules n their gaseous states: hydrogen, nitrogen, oxygen, fluorine, chlorine, bromine and iodine. Boron is NOT included in this list.
3. Which of the following are heteronuclear diatomic elements with a covalent bond?
MgO
CaO
HF
BaO
Explanation: MgO, CaO and BaO all have ionic bonds. The elements H and F are both nonmetals, so this is a covalent bond.
4. Which of the following is a homonuclear diatomic molecule that needs a slightly higher temperature than room temperature to exist in its gaseous state?
H2
Br2
ClF
I2
Explanation: H2 and Br2 can occur as gaseous homonuclear diatomic molecules at room temperature. ClF is a heteronuclear diatomic molecule. I2 needs a slightly higher temperature than room temperature to occur as a gaseous diatomic molecule.
5. Which of the following is NOT a diatomic molecule?
PCl3
NaCl
O2
BaO
Explanation: All are diatomic molecules except PCl3. Diatomic molecules are only made of two atoms. PCl3 has one P atom and three Cl atoms. Therefore, this is NOT a diatomic molecule.