I GENUINELY NEED THE ANSWER ASAP :o After a building is demolished, a contractor wants to separate a pile of rubble containing gravel, sand, iron nails, sawdust and concrete dust particles so he can recycle the parts. Use the following information to answer the following questions:
• concrete is made of limestone, which dissolves in acid
• sand is smaller than gravel
• iron is attracted to a magnet
• sawdust is less dense than water
Write a step-by-step process for the contractor to use to separate the 5 components of his rubble pile.

explanation:

let the different atoms be x and y. each with four protons and same mass will be represented as follows.

mass number is number of protons + number of neutrons.

            and  

since, it is given that one has a negative charge while the other is neutral. therefore, there will be increase in number of protons and the atom will be represented as follows.

according to periodic table, mass number of beryllium is 9 and it has atomic number 4 so, the atoms will be and .  

the protons and neutrons will be located inside the nucleus whereas the electrons will be revolving around the nucleus.  

1 is the answer to this problem

water and alcohols have similar properties because water molecules contain hydroxyl groups that can form hydrogen bonds with other water molecules and with alcohol molecules, and likewise alcohol molecules can form hydrogen bonds with other alcohol molecules as well as with water.