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I am Lyosha [343]
2 years ago
5

Please help chemistry timed test

Chemistry
2 answers:
Artist 52 [7]2 years ago
8 0

Answer:

Barrium nucleus has 56 protons and 137−56=81 neutrons.

Atomic Mass 137.327 atomic mass units

Number of Protons 56

Number of Neutrons 81

Number of Electrons 56

lakkis [162]2 years ago
7 0

Answer:

54

Barium atomic number is 56, this means that it has 56 protons in its nucleus and put it as a period 6 element. an uncharged barium atom would have 56 electron also. However as a group 2 element barium easily loses 2 electron to form the +2 cation. the ions has 56-2=54

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babymother [125]

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