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aev [14]
1 year ago
3

Someone pls explain how I do this work

Chemistry
1 answer:
Archy [21]1 year ago
3 0

Answer:

Explanation:


Element    #of protons     Mass #.      # of electrons      Atomic #.   Neutron

 Se.               34.                   78.96.                  34                     34           45
             

Si.                 14.                      28.                       14.                   14           14

         

H.                   1.                       1.                       1                         1               0


Ca.                  20.                 40.078.                20.                  20.              21

Fe.                  26.                  56.                         26.                 26.             30

Na.                  11.                    23.                       11.                    11.                12

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Iron is the most commonly used metal iron is extracted in a blast fumace from iron
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Answer:

70/100 X 2000 = 1400 tonnes of iron.

Explanation:

take the percentage of iron oxide and divide with overall amount of iron oxide using 2000 tonnes of hematite ore. 1400 tonnes of iron will be produced. this is not the percentage. if you want the percentage of iron produced just divide.

70/100 x 200 = 1400 tonnes of iron

percentage of iron produced = 70/1400 x 100 = 5 % of iron produced from 70% of iron oxide in 2000 tones of hematite ore

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3 years ago
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