Iron is found in Earth's crust as several iron compounds: Calculate the mass (in kg) of each compound that contains 6.3 × 10^3 kg of iron.

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The mass of 2.21 x 1040 atoms of iron (molar mass = 55.845 g/mol) is 2.78 x 104 g. 2.05 x 102 g 30.97 g. O 6.22 x 103g O 112 × 10-2 g.

What is the mass of 3.5 x 10^-3 molecules of copper (II) carbonate? Use correct significant figures and units.

1a) 1b)

1.) What is the molar mass for aluminum sulfate? Please use the atomic masses on the periodic table. Express your answer with the correct significant figures and units for molar mass. Mass Choices:  123.05 342.17 6.02 x 10^23 273.08 Unit Choices:  mol mol/g g g/mol 2.) How many grams are there in 5.699 moles of copper, Cu?  Express your answer with the appropriate significant figures and units.  0.08968 g/mol Cu 362.2 g/mol Cu 362.2 g Cu 0.08968 g Cu

Calculate the amount of anions (in moles) in 24.4 g of calcium iodate. Express your answer with three significant figures.

Crime scene investigators keep a wide variety of compounds on hand to help with identifying unknown substances they find in the course of their duties. One such investigator, while reorganizing their shelves, has mixed up several small vials and is unsure about the identity of a certain powder. Elemental analysis of the compound reveals that it is 67.31 % carbon, 6.978% hydrogen, 4.617% nitrogen, and 21.10% oxygen by mass.     Which of the compounds could the powder be? C17H19NO3C17H19NO3 = morphine, analgesic C17H21NO4C17H21NO4 = cocaine, illicit drug C7H5N3O6C7H5N3O6 = 2,4,6-trinitrotoluene (TNT), commonly used explosive C10H15NC10H15N = methamphetamine, stimulant C4H5N2OC4H5N2O = caffeine, stimulant C11H15NO2C11H15NO2 = 3,4-methylenedioxymethamphetamine (MDMA), illicit drug C21H23NO5C21H23NO5 = heroin, illicit drug C3H6NO3C3H6NO3 = hexamethylene triperoxide diamine (HMTD), commonly used explosive

A chemist prepares a solution of potassium bromide (KBr) by measuring out 31. mg of KBr into a 100. mL volumetric flask and filling to the mark with distilled water. Calculate the molarity of Br anions in the chemist's solution. Be sure your answer is rounded to the correct number of significant digits. alo mol L

A chemist adds  160.0mL  of a  ×9.310−5/molL  magnesium fluoride  MgF2  solution to a reaction flask. Calculate the mass in milligrams of magnesium fluoride the chemist has added to the flask. Be sure your answer has the correct number of significant digits. mg