Explanation:
Acids are substances whose ph is lower than 7.Acids react with most metals to form a salt and hydrogen gas.
Answer:- oxygen.
Explanations:- The electronic configuration is given and we are asked to figure out the electrically neutral atom that will have the electron configuration, 
.
The sum of electrons for this electron configuration is 8. If we look at the periodic table then 8 is the atomic number of oxygen.
So, the electrically neutral atom for the given electron configuration is oxygen.
Answer:
The identity of an atom is determined my the number of <u>protons</u>. This is the <u>atomic number</u>.
The particle(s) found inside the nucleus are called <u>protons and neutrons</u>. Their combined mass is referred to as <u>the mass number</u>.
Isotopes have the same number of <u>protons</u>, but different number of <u>neutrons</u>.
Option B, Bronze is made of the metals copper and tin.
Alloys are essentially materials that consist of two or more metal elements.
-T.B.
You can know the metal with low reactivity and the metal with high reactivity from the periodic table, as in metals the Chemical reactivity increases by going down a group, because of the farther down group we go the easier of lose and gain of electrons or the easier the electrons to be given or taken, this caused the chemical reactivity be higher.
- and the chemical reactivity decreases as we go across the period because they want to give away valence electrons, they need more energy to get rid of them.
