StoichiometryGas Volume and Mass Stoichiometry206Choose the best answerIn the reaction: 2NO + O₂ → 2NO₂ 560 cm³ NO₂ is produced at STP (273 K and 1 atm), while 50 mg O₂ remains unused. What were the initial masses of NO and O₂?A0.6 g NO and 0.4 g O₂B0.75 g NO and 0.45 g O₂C6.0 g NO and 4.5 g O₂D0.3 g NO and 0.37 g O₂ Like 0 Discuss 0Share
StoichiometryLimiting Reagent207Choose the best answerA limiting reagent is the reactant that:AIs consumed laterBIs consumed firstCRemains unchangedDIs always present in excess Like 0 Discuss 0Share
Stoichiometry#Atomic Structure#Isotopes208Choose the best answerWhich statement correctly defines relative atomic mass?AThe total number of protons and neutrons present in an atomBThe mass of the most abundant isotope of an elementCThe average mass of all atoms of an element relative to 1/12 of the mass of a carbon-12 atom, taking into account their natural isotopic abundancesDThe mass of an atom expressed in grams Like 0 Discuss 0Share
StoichiometryPercentage Composition by Mass209Choose the best answerWhat is the percentage of carbon by mass in CaCO₃?A6%B12%C40%D48% Like 0 Discuss 0Share
StoichiometryMolecular Formula and Molar Mass210Choose the best answerOne mole of a compound contains 1 mol C atoms and 2 mol O atoms. Its molar mass is:A3 g mol⁻¹B12 g mol⁻¹C32 g mol⁻¹D44 g mol⁻¹ Like 0 Discuss 0Share