The 3d orbital has lower energy--it fills before the 4s because of electron repulsion energies. I am studying acids and bases and it seems that it takes 2 which does not make sense to me. Beryllium has two valence electrons. The one electron in the 3d orbital and the two electrons in the 4s orbital are scandium's three valence electrons. Login to reply the answers Post; Anonymous. Br has 7 valence e-. Thanks. (1) 5 (2)3 (3)7 (4) 8 19. 5 years ago. Bromine has an electron configuration of 1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^10 4p^5 the valence electrons are in the 4s and 4p orbitals giving Bromine 7 valence electrons. Bromine has 7 valance electrons. This works if you are using the definition of valence shell to be the outermost shell.

Correct Answer: Correctc. Se(34)=1s²2s²2p⁶3s²3p⁶ 3d¹º 4s² 4p⁴. The outermost s & p electrons are considered to be the valence electrons for an atom, so …

Valence electrons … Selected Answer: Correctc. The valence electrons are in the 4th level, 4s2 + 4p5 = 7 valence electrons.
its 4 rows down, 2 from the end in the periodic table... Can anyone explain to me how the d orbitals effect the amount of valence electrons? Favorite Answer. 28 . Uploaded By hawraaal. You can find the how many electron in a. single atom by using a periodic table. All members of the family have seven valance electron hence the name 7A.

Luckily Oxygen (#O#) is in group 16, so it has 6 valence electrons. 1 decade ago. All of elements in this column have a charge of -1. This is a chemical element.

Asked in Atoms and Atomic Structure, Particle Physics How many protons and electrons in ion Br?

In chemistry, valence electrons are the electrons contained in the outermost, or valence, electron shell of an atom. Which element has the following ground-state electron configuration (Kry5s4d105p? If it is in the middle section (transition metals, Lanthanoids, or Actinoids), the rules are not so clear-cut. It does not include the transition metals.

1 decade ago.

How many electrons must a Sc atom lose to form a stable cation? A neutral bromine atom would also have 35 electrons. If you go the website below, you will see the electron configuration of bromine. 0 1 0.
(1)2 (2) 4 (3) 7 (4) 8 18.

The atomic number for bromine is 35, which means it has 35 protons in its atomic nuclei. no its not 35 that includes valence electrons. of selenium,we see . The column to its left has 7, then 6, and so on. How many electrons must a Sc atom lose to form a stable cation? (Beginning with principal quantum number 4, the s subshell has lower energy than the preceding period subshell, d; and so the 4s fills before the 3d.) Bromine's electron configuration, 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p5, shows that the third energy level is full, with 18 electrons (3s2 + 3p6 + 3d10), and therefore stable. Pages 28 This preview shows page 23 - … In order for a bromine atom to become a 1- bromide ion, it would have to gain an additional electron. This means they have six valence electrons. Br is a 7A element meaning there electron configuration would be ns2np7, but if you add an electron the it achieves noble gas configuration or if it lose one it would but …

The number of valence electrons is equal to their GROUP NUMBER, example: Mg is in IIA, therefore, it has 2 valence electrons... Br is in VIIA,therefore, it has 7 valence electrons A Br- ion would have 8 valence electrons if it has gained a electron and 6 if it has lost. From the above electron . It is located in the 3rd “8B” column, or Column 10) Thus, it is a transition metal.