Which of the following demonstrates how chemicals can help the
environment?

An empty fuel tank can still contain and therefore can be even more dangerous than one full of liquid fuel.

Avariable that is not being directly tested during an experiment should be changed varied experimented controlled

Read the chemical equation. 2c2h2 + 5o2 → 4co2 + 2h2o which of the following statements would be correct if one mole of c2h2 was used in this reaction? one mole of oxygen was used in this reaction. five moles of oxygen were used in this reaction. four moles of carbon dioxide were produced from this reaction. two moles of carbon dioxide were produced from this reaction.