It should be:
# of protons - # of electrons
It gives you the ion charge of the element. For example, Oxygen ion has 8 protons and 10 electrons. Therefore, 8 - 10 = -2 ----> O2-
The number of protons in an atom is equal to its atomic number. In a neutral atom, the number of electrons is equal to that of protons. If the atom is negatively charged, add it to the number of electrons; and if positive, subtract.
Look at the atomic number. That will be the number of protons and electrons; subtract that number from the atomic mass (rounding down) and you'll have the number of neutrons.
Find the atomic number. That tells you the number of protons and electrons (in a neutral atom). Then find the atomic weight. The number of protons plus the number of neutrons will equal the atomic weight. So if you know the wt. just subtract the number of protons and you will have the number of neutrons.
From the periodic table, potassium has an atomic number of 19. This means that potassium atoms have 19 protons in their nuclei. In a neutral atom, the number of protons equals the number of electrons. Therefore, potassium atoms have 19 electrons. Mass number is the sum of protons and neutrons in the nucleus of an isotope. If you know the mass number and number of protons, subtract the number of protons from the mass number. In the case of potassium-31, the mass number is 31. So, subtract 19 from 31 and you get 12, which is the number of neutrons. So the atoms of potassium-31 has 19 protons, 19 neutrons, and 12 neutrons.
To find out the number of electrons in an element you must add the protons and neutrons and subtract that number with the atomic mass, this will determine the amount of electrons because the unknown element could be an isotope and have more than the normal amount of electrons of the non isotope element.
The number of protons in an atom is equal to its atomic number. In a neutral atom, the number of electrons is equal to that of protons. If the atom is negatively charged, add it to the number of electrons; and if positive, subtract.
Look at the atomic number. That will be the number of protons and electrons; subtract that number from the atomic mass (rounding down) and you'll have the number of neutrons.
If its a neutral atom, there will be the same number of protons as electrons. The atomic number will tell you how many protons there are, so there are 50 protons and 50 electrons.The mass number is the sum of the number of protons (or electrons in a neutral atom) and the number of neutrons. Since we know there are 50 protons, we subtract 125 with 50 to get 75 neutrons.
Find the atomic number. That tells you the number of protons and electrons (in a neutral atom). Then find the atomic weight. The number of protons plus the number of neutrons will equal the atomic weight. So if you know the wt. just subtract the number of protons and you will have the number of neutrons.
Subtract the atom number from the mass number to get the neutron. Mass number is the sum of neutrons and electrons. Atom number is the number of electrons. the number of electrons is equivalent to the number of protons.
From the periodic table, potassium has an atomic number of 19. This means that potassium atoms have 19 protons in their nuclei. In a neutral atom, the number of protons equals the number of electrons. Therefore, potassium atoms have 19 electrons. Mass number is the sum of protons and neutrons in the nucleus of an isotope. If you know the mass number and number of protons, subtract the number of protons from the mass number. In the case of potassium-31, the mass number is 31. So, subtract 19 from 31 and you get 12, which is the number of neutrons. So the atoms of potassium-31 has 19 protons, 19 neutrons, and 12 neutrons.
Atomic number means number of protons present in an atom. Atomic number= number of protons. mass number = number of neutrons+ number of protons. So if you subtract the number of protons you get neutrons and if you subtract neutrons you get protons. mass number - protons= neutrons Mass number - neutrons = protons.
The number of protons for any element is the atomic number. The number of electrons is equal to the number of electrons. To find the number of nuetrons you must subtract the atomic number from the mass number mass number-atomic number= number of nuetrons protons=electron the number of protons in the element aluminum is 13. The number of electrons is 13.
Bromine has the atomic number 35, so it has 35 protons. To find the number of neutrons in Bromine-80, subtract the atomic number from the atomic mass: 80 (atomic mass) - 35 (protons) = 45 neutrons. Since it is a neutral atom, the number of protons and electrons are the same, so there are 35 electrons.
The atomic number is how many protons there are, and since the number of protons is equal to the number of electrons, it is also the number of electrons. You can take the number of protons away from the atomic weight (overall weight) which will give you the number of neutrons. (Electrons don't weigh anything in the atomic weight so you don't need to subtract this as well). Hope this helps :D
To find out the number of electrons in an element you must add the protons and neutrons and subtract that number with the atomic mass, this will determine the amount of electrons because the unknown element could be an isotope and have more than the normal amount of electrons of the non isotope element.
The charge of an ion can be calculated by adding up the protons and subtracting the electrons. When oxygen with 8 protons has 8 electrons it is neutral, when it has 7 electrons it is positively charged.