Question

analysis: answer the following questions: 1. which molecules are not compounds? 2. plastic ‘sticks’ are used to hold ‘atoms’ together in this activity. is this a good way to represent covalent bonds? why or why not? 3. which molecule(s) has a double bond? a. highlight the double bonds in yellow. 4. which molecule(s) has a triple bond? a. circle any triple bonds with a green pen/pencil. 5. what are the differences between single, double & triple covalent bonds? 6. how many different elements in glucose? 7. glycine is an amino acid. how many total atoms are in the glycine molecule you built? 8. how many different elements in the glycine? 9. draw an atomic model for a carbon, nitrogen & oxygen atom, showing all the electrons. i have given you hydrogen as an example:

Explanation:

Step1: Define compound

A compound is a substance made up of two or more different types of elements chemically combined. So, molecules made of only one - type of element are not compounds. For example, $O_2$ (oxygen molecule) is not a compound as it consists of only oxygen atoms.

Step2: Evaluate plastic - stick model for covalent bonds

Plastic sticks can be a good way to represent covalent bonds in a simple, visual way. Covalent bonds involve the sharing of electrons between atoms, and the sticks can represent the connection between atoms. However, they do not show the electron - sharing aspect directly.

Step3: Identify double - bond molecules

Double - bond molecules have a bond where two pairs of electrons are shared between atoms. For example, in carbon dioxide ($CO_2$), there are double bonds between carbon and oxygen ($C = O$).

Step4: Identify triple - bond molecules

Triple - bond molecules have a bond where three pairs of electrons are shared between atoms. For example, in nitrogen gas ($N_2$), there is a triple bond between the two nitrogen atoms ($N\equiv N$).

Step5: Differentiate covalent bonds

Single covalent bonds share one pair of electrons, double covalent bonds share two pairs of electrons, and triple covalent bonds share three pairs of electrons. Double bonds are shorter and stronger than single bonds, and triple bonds are shorter and stronger than double bonds.

Step6: Determine elements in glucose

The chemical formula of glucose is $C_6H_{12}O_6$. There are 3 different elements: carbon (C), hydrogen (H), and oxygen (O).

Step7: Count atoms in glycine

The chemical formula of glycine is $C_2H_5NO_2$. The total number of atoms is 2 (C) + 5 (H)+1 (N)+2 (O)=10 atoms.

Step8: Determine elements in glycine

In glycine ($C_2H_5NO_2$), there are 4 different elements: carbon (C), hydrogen (H), nitrogen (N), and oxygen (O).

Step9: Draw atomic models

• Carbon (C): Atomic number is 6. It has 2 electrons in the first shell and 4 electrons in the second shell. Draw a nucleus with 6 protons and 6 neutrons (approximate), and two electron - shells with 2 electrons in the inner shell and 4 electrons in the outer shell.
• Nitrogen (N): Atomic number is 7. It has 2 electrons in the first shell and 5 electrons in the second shell. Draw a nucleus with 7 protons and 7 neutrons (approximate), and two electron - shells with 2 electrons in the inner shell and 5 electrons in the outer shell.
• Oxygen (O): Atomic number is 8. It has 2 electrons in the first shell and 6 electrons in the second shell. Draw a nucleus with 8 protons and 8 neutrons (approximate), and two electron - shells with 2 electrons in the inner shell and 6 electrons in the outer shell.

Answer:

1. Molecules made of only one type of element are not compounds, e.g., $O_2$.
2. Plastic sticks can be a simple visual representation but do not show electron - sharing directly.
3. Examples include $CO_2$ with $C = O$ double bonds.
4. Examples include $N_2$ with $N\equiv N$ triple bonds.
5. Single bonds share 1 pair of electrons, double bonds share 2 pairs, triple bonds share 3 pairs; double and triple bonds are shorter and stronger than single bonds.
6. 3 (carbon, hydrogen, oxygen).
7. 10.
8. 4 (carbon, hydrogen, nitrogen, oxygen).
9. Carbon: Nucleus with 6 protons and 6 neutrons, 2 electrons in first shell, 4 in second shell. Nitrogen: Nucleus with 7 protons and 7 neutrons, 2 electrons in first shell, 5 in second shell. Oxygen: Nucleus with 8 protons and 8 neutrons, 2 electrons in first shell, 6 in second shell.