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Masja [62]
3 years ago
15

The period 4 alkaline-earth metal has the name_______ . An isotope of this element having 20 neutrons has amass numberof _______

Chemistry
1 answer:
Cerrena [4.2K]3 years ago
6 0

Answer:

The period 4 alkaline-earth metal has the name Calcium. An isotope of this element having 20 neutrons has a mass number of 40.

Explanation:

Looking at the periodic table 4th row for the alkaline-earth metal, we can find Calcium which has an atomic number of 20 (or protons number, or z). The mass number is given by the sum of protons and neutrons. If the number of protons in this case is 20 and the number of neutrons is also 20, the mass number A = 40.

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The molecular mass of H₂S is 34 gram per mole.  

Number of moles is determined by using the formula,  

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