H2SO4 is referred to as a strong acid and is denoted as option A.
<h3>What is an Acid?</h3>
This refers to any substance which tastes sour when in water and changes the color of blue litmus paper to red. It is usually very corrosive and are used in industries for different functions.
H2SO4 is referred to as a strong acid because it dissociates completely in its aqueous solution or water.
Read more about Acid here brainly.com/question/25148363
#SPJ1
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.