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VashaNatasha [74]
3 years ago
12

I need help

Chemistry
1 answer:
Liono4ka [1.6K]3 years ago
6 0

Answer:

d and e - Sodium and antimony

Explanation:

The atomic numbers remain the same, while the mass numbers change (because neutrons are being added or taken away).

sodium has an atomic number of 19 and a mass number of 39 - in d, it has an atomic number of 19 but a mass number of 40. therefore, it is an isotope

antimony has an atomic number of 51 and a mass number of 121.60 - in e, it has an atomic number of 51, but a mass number of 123. therefore, it is an isotope

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ivanzaharov [21]

We have to get the stable atom formed after positron emission from Terbium-147.

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3 years ago
If an unknown quantity of gas is held at a temperature of 789 K in a container with a volume of
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