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.
B directly; inversely
Pressure and volume have an inverse relationship (when one increases the other increases) while volume and temperature are direct (if one increases so does the other)
Note: these relationships are only true if other factors are constant such as the temperature, and amount (in moles).
Answer: Option (d) is the correct answer.
Explanation:
An atom or element which has the ability to readily gain an electron will have high electronegativity.
Both Beryllium and Calcium are alkaline earth metals and hence they are electropositive in nature.
Whereas both iodine and nitrogen are electronegative in nature. But across the period there is an increase in electronegativity and down the group there is a decrease in electronegativity.
Nitrogen belongs to period 2 and iodine belongs to the bottom of group 17. Thus, we can conclude that nitrogen is more electronegative than iodine.
