Question

***55 POINTS, ASAP, PLEASE HELP!!!***

Step 1: Predict the products of a chemical reaction.

a) Use your knowledge of atoms, bonding, and the periodic table to complete the chemical equation and predict the products of the chemical reaction.


CH4 + O2 ----> ________


Label this equation “Initial

Prediction.”


Step 2: Explain your prediction.

a) Write a few paragraphs predicting the products of the chemical reaction and explaining why you

made this prediction. Your paragraphs should include:

i. identify the products of the chemical reaction.

ii. explain why these are the products based on trends in the periodic table (the number of

valence electrons, electronegativity, etc.).

iii. identify the types of bonds in the reactants and products.

iv. identify the number of each type of bond in the reactants and products.

v. identify the type of reaction.

b) Label these paragraphs “Initial Explanation.”


Step 4: Create Lewis dot diagrams.

a) Draw Lewis dot diagrams of the reactants and products on the paper with your chemical equation.

b) Select a different color to use for each element in the chemical reaction. Use your chosen color

for the element’s symbol and for its valence electrons.

c) Label these diagrams “Lewis Dot Diagrams.”


Step 5: Review and revise your prediction and explanation.

a) First, review your initial prediction and explanation by comparing it to your Lewis dot diagrams. If

the results of your Lewis dot diagrams are different from your initial prediction, you will need to

revise your prediction and explanation.

b) Next, review your prediction and explanation to determine whether they adhere to the law of

conservation of mass. If they do not, you will need to revise your prediction and explanation so

that mass is conserved.

c) Finally, determine whether your explanation addresses trends in the periodic table and how they

can be used to predict outcomes of chemical reactions. If it does not, you will need to revise your

explanation to include a discussion of periodic trends and how they help predict the outcomes of

chemical reactions.

Answer 1

Initial Prediction:
CH4 + O2 ----> CO2 + H2O

Initial Explanation:
The reaction between methane (CH4) and oxygen (O2) is a combustion reaction, which produces carbon dioxide (CO2) and water (H2O). This reaction occurs because methane is a hydrocarbon, which means it contains hydrogen and carbon atoms. Oxygen is a highly reactive element, and it readily reacts with hydrocarbons to produce carbon dioxide and water.

The Lewis dot diagram for methane shows that it has four valence electrons, which it shares with four hydrogen atoms to form four covalent bonds. Oxygen has six valence electrons, and it forms two covalent bonds with two oxygen atoms to form O2. The combustion reaction between methane and oxygen breaks the covalent bonds in both reactants and forms new covalent bonds in the products. In the products, carbon dioxide has two double bonds between carbon and oxygen atoms, and water has one covalent bond between oxygen and hydrogen atoms.

The types of bonds in the reactants are covalent bonds, while the types of bonds in the products are also covalent bonds. The number of each type of bond in the reactants and products are as follows:
Reactants:
4 C-H bonds
1 O=O bond
Products:
2 C=O double bonds
2 O-H bonds

The total mass of the reactants is equal to the total mass of the products, which means that the law of conservation of mass is satisfied. Therefore, the balanced chemical equation for the combustion of methane is:
CH4 + 2O2 ----> CO2 + 2H2O

Lewis Dot Diagrams:
CH4: H
|
H--C--H
|
H

O2: O=O

CO2: O
||
O=C=O

H2O: H
|
H--O--H