2C4H10 + 13O2 = 8CO2 + 10H2O
1. (2.06g C4H10)/(58.12 g/mol C4H10) = 0.035mol C4H10
2. (0.035molC4H10)(10 mol H2O/2mol C4H10) = 0.177mol H2O
3. (0.177mol H2O)(18.01g/mol H2O) = 3.19g H2O
Answer: Option (C) is the correct answer.
Explanation:
When chemical composition of a substance is not changing in a chemical reaction then it is known as a physical change.
For example, when water change state, from ice to steam then it means solid state is changing into gaseous state.
Therefore, it is a physical change.
And, a reaction which causes change in chemical composition is known as a chemical change.
For example, 
Thus, we can conclude that we can see water change state, from ice to steam. This is a physical change in matter.
Answer:
DNA
Explanation: Because if you stretch DNA it gets longer.