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.
Answer:
the answer that you are looking for is d
Explanation:
Answer:
Name the element: Beryllium
Number of shells: 4
Valence electrons: 2
Explanation:
Answer:
Metal
Non-metal
Explanation:
CaF2 is an ionic compound. Ionic compounds are mostly composed of a metal and a non metal. Metals donate electrons to non-metals to form ionic compounds.
Calcium is a divalent ion of group two in the periodic table while F is a univalent nonmetal of group 17 in the periodic table. Hence the compound CaF2 is composed of a metal and a nonmetal.
Answer:
last choice
Explanation:
oxidation and reduction can be defined in terms of adding or removing oxygen to a compound
oxidation is gaining oxygen
reduction is to loss oxygen