Help me, brainiest if correct

Calculate the molar mass of aluminum oxide (al2o3). express your answer to four significant figures.

The number at the end of an isotope’s name is the number.

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.