What is the mass of 7.00 moles of H2O2

0.206 mol H₂O₂

General Formulas and Concepts:

Chemistry - Atomic Structure

Explanation:

Step 1: Define

7.00 moles H₂O₂

Step 2: Identify Conversions

Molar Mass of H - 1.01 g/mol

Molar Mass of O - 16.00 g/mol

Molar Mass of H₂O₂ - 2(1.01) + 2(16.00) = 34.02 g/mol

Step 3: Convert

= 0.205761 mol H₂O₂

Step 4: Check

We are given 3 sig figs. Follow sig fig rules and round.

0.205761 mol H₂O₂ ≈ 0.206 mol H₂O₂

answer is: c. the experiment shows that the red substance experienced a chemical change.

this is chemical change (chemical reaction), because two new substances are formed (metalig liquid and gas), the atoms are rearranged and the reaction is followed by an energy change.

this is example of chemical decomposition.

chemical decomposition (analysis) is the separation of a single chemical compound into its two or more elemental parts or to simpler compounds.  

chemical decomposition is opposite of chemical synthesis.

i believe the answer is true.