4.Let’s say I hand you 2 mineral samples, and tell you that one is pyrite and the other is magnetite.?
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A. Pyrite and magnetite are both from the same crystal system. That means they form crystals in a similar shape or pattern. They are both from the isometric system. They will both be blocky crystals but may not be exactly the same. Perfect pyrite crystals are cube shaped or diploidal (see:http://webmineral.com/data/Pyrite.shtml), and magnetite is an octahedron (see: http://webmineral.com/data/Magnetite.shtml).\n\nHardness of magnetite is 5 1/2-6 on Mohs scale and pyrite is 6- 6 1/2.  \n\nBoth have conchoidal fracture. (Quartz has conchoidal fracture in case you need to picture this)\n\nBoth have a similar density. Pyrite has a density of 4.8-5 g/cc and magnetite has a density of 4.95 gm/cc.\n\nBoth have a metallic luster. \n\nB. The best way to distinguish between them is to use a streak test. Magnetite will be grayish-black and pyrite will be greenish-black.\n\nThe other major difference is that magnetite will be naturally magnetic, and pyrite will not be. \n\n\nThe lesson here is to learn think of your different properties as sort of a tool kit. Decide which properties are useful and which ones will not be useful for the particular samples you are testing. Be sure to be familiar with all of the properties you can use. A list would be:\na. cleavage\nb. color (one of the least reliable)\nc. density\nd. luster\ne. fracture\nf. crystal habit (can be confusing because some minerals have several possible)\ng. hardness (know the hardness of common tests like a penny, a knife, a quartz crystal, glass, etc.)\nh. streak\ni. magnetism\nj. taste (best test for Halite or sylvite)\nk. There are lots more that involve using thin sections in a microscope, and X-ray diffractometer, etc.
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Ferromagnesium minerals: silicates with iron and magnesium in their formula, dark colored and dense. Example includes hornblende. \nNonferromagnesium mineral: silicates with no iron or magnesium in their formula (calcium, sodium or potassium common), light colored. Example includes feldspar.
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Question 1 used if three or more things to distinguish. Question 2 used if only 2 things to distinguish
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Fe2O3(s) + 3 CO(g) ----> 2 Fe(l) + 3 CO2(g)\n\nCount up the oxygens; the left side and right side oxygens should match.
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What extract are you talking about? Different materials require different extraction methods.
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FeCl3 + NaCl -> FeCl2 + NaCl3\n\n\nFeCl3 + NaCl -> FeCl2 + NaCl3\n\nthese reactions are not possible \nas this reaction can take place if iron(fe) was more reactive than sodium or fe was less electropositive than na\nhence \nthese reactions are not possible
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I don't know but if you click on the site below you'll find out real quick. They know minerals.
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Pb(SO4)2\nPbSO4  is lead (II) sulfate!
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The best test is a streak test. If you are not familiar with this, it is when you rub the mineral across a piece of unglazed porcelain plate or tile.\n\nIn a streak test the gold will leave behind a gold streak while pyrite will leave behind a black one. This works, trust me, I know. All you need is a piece of unglazed porcelain.\n\nYou said earlier about rubbing it across the skin. I have never seen this work however some cheap jewlery is made of pyrite & will leave the fingers, etc. black looking. That is after you wear it a while.\n\nGold is very dense for its size. Pyrite is not nearly as dense. You could do a density test by displacement in water but I assume from what you told me that the "gold" is in a matrix.\n\nPyrite is usually found as a mass of cubic crystals. Sometimes they take on the appearance of a nugget b/c the cubes are very tiny. Gold will not have these cubes.\n\nGold is sometimes found in quartz veins. If you have a chunk of quartz it is possible that there is some gold in there.\n\nGo with the streak test & let us know what happens.\n\n:)
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Iron and lead are both elements, so in their pure form, they wouldn't contain any trace of the other.\n\nIn a given sample of rock, however, iron and lead might both be present in some quantity, along with other substances.  The percentage would depend on the sample, and would vary depending on the source.  However, the iron itself would still not contain lead.
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K2S\n\nPotassium is K.  Sufide is S2-, so you need 2 K's.
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yes you are right.. there are two sets of electrons
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4Fe3+ + 9O2 ->  6Fe2O3
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I believe it is iron.  Not an expert though.
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This lab involves putting iron (steel wool) into a solution of copper sulphate. The reaction produces metallic copper and iron sulphate solution. I've never been really sure if it's iron(II) sulphate or iron(III) sulphate as the product. I've used both equations with good results. \n\n   Fe   +  CuSO4   --->  Cu  +  FeSO4\n   2 Fe   +  3 CuSO4   --->  3 Cu  +  Fe2(SO4)3\n\n\nFor prelab, make up a saturated copper(II) sulphate solution\nTrust me. Otherwise, the kids will be filtering for hours.  \n\nHave containers available for appropriate disposal of reagents. And make sure they clean up all of the bits of steel wool from the lab benches. Those little bits will haunt you for weeks if they don't.\n\n\n\n\nMethod\n\n1. Obtain 100 mL of copper (II) sulphate solution in\n   a clean, dry beaker. \n\n2. Obtain about 10 g of steel wool. Record the exact mass.\n \n3. Place the steel wool into the copper(II) sulphate solution.  Stir with a glass rod. When the solution loses its blue colour, add more copper(II) sulphate solution.\n\n4. Continue stirring (and adding solution, if necessary)until the strands of steel wool are no longer apparent, and only particles of a reddish brown solid are visible.\n\n5. Record the mass of a piece of filter paper.\n   Place it into a funnel.\n \n6. Pour the mixture through filter paper in a funnel.\n   Rinse any residue in the beaker into the filter        paper      with distilled water. Rinse the solid in the filter paper with distilled water.\n\n7. Allow the solid and filter paper to dry, then find the combined mass.\n\n\nAnalysis\n\n1. If iron was the limiting reactant, predict the mass of copper which should have been formed. Show work.\n  \n2. Calculate the percentage difference between  the mass of copper predicted in question 1 and the actual amount of copper produced. Show all work.\n\n3. Discuss possible explanations for your results in question 2.\n\n\n\nGood luck !
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Ferric sulfite, or iron (III) sulfite
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Get two pieces of iron block. Turn a coil round one of them. Pass electric current through the one which has the coil turned round it. This will make the coiled piece of iron act like a magnet and will attract the other piece of iron. And you have made an electromagnet.