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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<h3>The treatment and disposal of Mercury:</h3>
- Heating and incineration can release the mercury vapor into atmosphere causing atmospheric pollution. The process of solidification and disposal into secured landfill, gas phase recovery of mercury, and thermal treatment is gaining interest in mercury treatment and recovery field by various researchers and industries.
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1.35atm(760mmHg/1atm)=1026mmHg
Every cell has a nucleus unless it is RNA which is involved with DNA movement