:d juan thinks that water will evaporate faster in a warm place than in a cool one. he has two identical bowls and a bucket of water. he wants to do an experiment to find out if he is correct. which one of the following should he do? place a bowl of water in a cool place and a bowl holding twice as much water in a warm place. place a bowl of water in a cool place and a bowl holding half as much water in a warm place. place a bowl of water in a cool place and a bowl holding the same amount of water in a warm place. place two bowls holding the same amount of water in a warm place.

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.

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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.