What is the minimum mass of magnetite Fe3O4, a iron ore, from which 7.5kg of pure iron could be extracted? Be sure your answer has a unit symbol, if necessary, and is rounded to the correct number of significant digits.

Hannah is writing a report on how albedo affects the global climate. she’s proofreading her passage for any factual errors. which sentence must hannah correct before submitting her report? earth receives energy from the sun. this energy drives many of the processes on earth, including its climate. some part of this energy is reflected by earth’s surface. we use the term albedo to describe the reflected energy. albedo of an object is the ratio of the reflected radiation to the total radiation reaching the object. a value of 0 means no energy is absorbed by the object, whereas a value of 1 means that all of the energy is absorbed. in this way, the albedo of an object can influence earth’s atmospheric temperature.

Idon't really understand this can you me and show your work.☺☺[ chemistry b] subject [ electron transfer in lonic bonds]grade( 12)

100 grams of molten lead (600°c) is used to make musket balls. if the lead shot is allowed to cool to room temperature (21°c), what is the change in entropy (in j/k) of the lead? (for the specific heat of molten and solid lead use 1.29 j/g⋅°c; the latent heat of fusion and the melting point of lead are 2.45 × 104 j/kg and 327°c, respectively.)