Question

1. choose the best answer.

the electrolysis of water into oxygen and hydrogen is shown in the following equation.
what type of reaction is the electrolysis of water?
2h₂o → 2h₂ + o₂
single replacement
double replacement
decomposition reaction
synthesis reaction

1. choose the best answer.

a student observes the combustion reaction of methane (ch₄) upon lighting a bunsen burner. which
the reaction?
carbon and water

Explanation:

Question 3

To determine the reaction type, analyze the equation \(2\text{H}_2\text{O}
ightarrow 2\text{H}_2 + \text{O}_2\). A decomposition reaction is when a single compound breaks down into simpler substances. Here, water (\(\text{H}_2\text{O}\)) breaks into hydrogen (\(\text{H}_2\)) and oxygen (\(\text{O}_2\)), fitting decomposition. Single replacement involves one element replacing another, double replacement involves two compounds exchanging ions, and synthesis is combining substances (opposite of decomposition).

Answer:

decomposition reaction

Question 4 (Note: The question text is incomplete, but assuming it's about products of methane combustion: The combustion of methane (\(\text{CH}_4\)) in oxygen produces carbon dioxide (\(\text{CO}_2\)) and water (\(\text{H}_2\text{O}\)), so if options include "carbon dioxide and water", that would be correct. However, with the given partial text, if the option was "carbon and water" (as seen), that's incorrect. But since the question is cut off, we can only address based on visible info. If we assume the question is "Which are the products of the reaction?", the correct products are \(\text{CO}_2\) and \(\text{H}_2\text{O}\), so "carbon and water" is wrong. But since the user's question 4 is incomplete, we can't fully answer, but for the visible part, if we had to choose from the given (incomplete) options, the correct product set for \(\text{CH}_4 + 2\text{O}_2

ightarrow \text{CO}_2 + 2\text{H}_2\text{O}\) is carbon dioxide and water, not "carbon and water".)

(For the sake of providing a response based on the visible part of question 4, if we assume the options are as seen: "carbon and water" is incorrect. The correct products of methane combustion are carbon dioxide (\(\text{CO}_2\)) and water (\(\text{H}_2\text{O}\)).)