I need help on a few of these.
A. How many protons are in one atom of fluorine - 19?
B. How many neutrons are in one atom of potassium - 39?
C. How many electrons are in one neutral atom of V - 51?
D. What is the symbol for the element that has 78 protons?
E. What is the symbol for the neutral atom that has 52 electrons?
You are missing quite a lot here.
Look up these definitions: Atomic number; atomic mass number
Then go here
http://www.ptable.com/
I will be happy to check your work.
A. To find the number of protons in one atom of fluorine - 19, we need to look at its atomic number. The atomic number represents the number of protons in an atom. The atomic number of fluorine is 9. Therefore, there are 9 protons in one atom of fluorine - 19.
B. To determine the number of neutrons in one atom of potassium - 39, we need to subtract the atomic number from the mass number. The atomic number of potassium is 19 (as indicated by its position on the periodic table), and the mass number is 39. Subtracting the atomic number from the mass number, we get (39 - 19 = 20). Hence, there are 20 neutrons in one atom of potassium - 39.
C. To find the number of electrons in one neutral atom of V - 51, we again rely on the atomic number. The atomic number of vanadium (V) is 23. In a neutral atom, the number of electrons is equal to the number of protons. Therefore, there are 23 electrons in one neutral atom of V - 51.
D. The symbol for an element represents its atomic symbol. To determine the symbol for the element with 78 protons, we consult the periodic table. The element with 78 protons is platinum (Pt).
E. The symbol for a neutral atom represents its element. To find the symbol for a neutral atom with 52 electrons, we look on the periodic table for an element that has an atomic number (number of protons) equal to 52. The element with atomic number 52 is tellurium (Te), so its symbol is Te.