Hexanes is ... Select one: a. a mixture of hexane isomers. b. a royal plural like "We are not amused!". c. impure hexane. d. a mixture of hydrocarbons with the boiling point close to that of hexane. e. a mixture of normal and iso-hexanes.

Inside a flashbulb, oxygen surrounds a thin coil of magnesium. when the flashbulb is set off, a chemical reaction takes place in which magnesium combines with oxygen to form magnesium oxide. which of the chemical equations matches the reaction above? a. mg + o2 mgo2 + energy b. 2mg + o mg2o + energy c. 2mg + o2 2mgo + energy d. mg + o mgo + energy

The number of moles of a given mass of a substance can be found without knowing its molecular formula or molar mass. true false

Asample of hydrated tin (ii) chloride (sncl2) has a mass of 4.90 g. when it is dehydrated, it has a mass of 4.10 g. which is the correct chemical formula for the hydrate? sncl2•2h2o          sncl2•4h2o          sncl2•6h2o