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3 years ago

Please help me. ? :)

Chemistry

1 answer:

BaLLatris [955]3 years ago

3 0

Answers and explanation:

To answer these questions you use a periodic table.

A is In because it has 49 protons and In is element number 49.

B is 27 because Co is element number 27.

C is 73 because Ta is element number 73.

D is 49 because the number of electrons in an atoms is always equal to the number of protons.

E is 56 because the atomic number of Ba is 56.

F is 54 because 56 - 54 = 2. The charge is equal to the number of protons minus the number of electrons.

G is 66. The number of neutrons is equal to the atomic mass minus the number of protons. 115 - 49 = 66.

H is 108 because 181 - 73 = 108.

I is 32. The atomic mass of an element is equal to the amount of protons plus the amount of neutrons. So 16 + 16 = 32.

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Se realiza una mezcla de minerales de Cu y Fe: 20 kg FeS2 (pirita), 70 kg de Fe2O3 (hemetita) 15 kg de CuFe2 (calcopirita) y 90

Artemon [7]

Answer:

34.78% Fe

39.66% Cu

5.48% S

20.07% O

Explanation:

Para resolver esta pregunta debemos hallar la masa de cada átomo en cada mineral. Así, podremos hallar el porcentaje de cada átomo:

Pirita (Fe: 55.845g/mol; S: 32.065g/mol; FeS2: 119.975g/mol)

Masa Fe:

20kg FeS2 * (1*55.845g/mol / 119.975g/mol) = 9.31kg Fe

Masa S:

20kg FeS2 * (2*32.065g/mol / 119.975g/mol) = 10.69kg S

Hemetita (Fe: 55.845g/mol; O: 16g/mol; Fe2O3: 159.688g/mol)

Masa Fe:

70kg Fe2O3 * (2*55.845g/mol / 159.688g/mol) = 48.96kg Fe

Masa O:

70kg Fe2O3 * (3*16g/mol / 159.688g/mol) = 21.04kg O

Calcopirita (Fe: 55.845g/mol; Cu: 63.546g/mol; CuFe2: 175.236 g/mol)

Masa Fe:

15kg CuFe2 * (2*55.845g/mol / 175.236 g/mol) = 9.56kg Fe

Masa Cu:

15kg CuFe2 * (1*63.546g/mol / 175.236 g/mol) = 5.44kg Cu

Tenorita (O: 16g/mol; Cu: 63.546g/mol; CuO: 79.545 g/mol)

Masa O:

90kg CuO * (1*16g/mol / 79.545 g/mol) = 18.10kg O

Masa Cu:

90kg CuO * (1*63.546g/mol / 79.545 g/mol) = 71.90kg Cu

Masa Total: 20kg + 70kg + 15kg + 90kg = 195kg

Porcentaje Hierro:

9.31kg Fe + 48.96kg Fe + 9.56kg Fe / 195kg * 100 =

34.78% Fe

Porcentaje Cobre:

5.44kg Cu + 71.90kg Cu / 195kg * 100 =

39.66% Cu

Porcentaje Azufre:

10.69kg S / 195kg * 100 =

5.48% S

Porcentaje Oxígeno:

21.04kg O + 18.10kg O/ 195kg * 100 =

20.07% O

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