HELP How much of a 1.0 g polonium-214 sample remains after 818 microseconds? The half life of polonium-214 is 163.7 microseconds.

All of the following are part of the biosphere except

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.

What volume would 2.25 moles of ne has occupy at stp?