Question

give the symbol and number of protons in one atom of: lithium, iron, oxygen, krypton, bromine, copper, mercury, helium. give the symbol and number of electrons in a neutral atom of: uranium, boron, chlorine, iodine, xenin. give the symbol and number of neutrons in one atom of:

Explanation:

Step1: Recall element symbols and proton - number facts

The number of protons in an atom is equal to its atomic number. We use the periodic table to find element symbols and atomic numbers.

Step2: For Bromine

The symbol is Br and the atomic number (number of protons) is 35.

Step3: For Copper

The symbol is Cu and the atomic number (number of protons) is 29.

Step4: For Mercury

The symbol is Hg and the atomic number (number of protons) is 80.

Step5: For Helium

The symbol is He and the atomic number (number of protons) is 2.

Step6: For Chlorine

The symbol is Cl and the atomic number (number of electrons in a neutral atom = number of protons) is 17.

Step7: For Iodine

The symbol is I and the atomic number (number of electrons in a neutral atom = number of protons) is 53.

Step8: For Xenon (assuming you meant Xenon instead of Xenin)

The symbol is Xe and the atomic number (number of electrons in a neutral atom = number of protons) is 54.

Answer:

Bromine: Br, 35
Copper: Cu, 29
Mercury: Hg, 80
Helium: He, 2
Chlorine: Cl, 17
Iodine: I, 53
Xenon: Xe, 54