Two. One hydrogen atom has one valence electron, so two hydrogen atoms will have two valence electrons :)
Hydrogen has 1 valence electron, whereas helium has 2 valence electrons.
Nitrogen has five valence electrons, while hydrogen has one valence electron. To achieve a stable configuration, nitrogen typically forms three bonds with hydrogen atoms, utilizing three of its valence electrons. Therefore, the correct formula when nitrogen bonds with hydrogen is NH₃, or ammonia.
Acetylene (C2H2) has 2 valence electrons for each carbon atom and 1 valence electron for the hydrogen atoms. Therefore, acetylene has a total of 10 valence electrons (4 from carbon and 6 from hydrogen).
H2O2 is a compound, and the concept of "valence electrons" applies to atoms but not to compounds. If the question is or should be intended to be, "How many valence electrons did the atoms in one formula unit of H2O2 have before they reacted to form the compound?", the answer is one from each hydrogen atoms and six from each oxygen atom, for a total of 14.
the number of valence electrons determine the reactivity of the atoms
The number of valence electrons in cyclopentadiene C5H6 is 54. Carbon has 4 valence electrons and hydrogen has 1, giving a total of 30 for carbon atoms and 24 for hydrogen atoms.
Hydrogen has 1 valence electron, whereas helium has 2 valence electrons.
The number of valence electrons in CH2O is 14. Carbon contributes 4, each of the two hydrogen atoms contributes 1, and oxygen contributes 6 valence electrons.
A molecule of ammonia (NH3) has 8 valence electrons - 5 from nitrogen and 1 each from the three hydrogen atoms.
H2 is not an atom, it is a diatomic molecule. Each hydrogen atom has 1 valence electron. When two hydrogen atoms covalently bond to form an H2 molecule, there are two valence electrons being shared by the two atoms.
Silicone has 4 valence electros so it would need 4 hydrogen atoms to give itself an octet of valence electrons.
Hydrogen has 1 valence electron. Bromine has 7 valence electrons. When hydrogen and bromine react, the bromine atom 'steals' the hydrogen atom's only electron. The hydrogen atom then has no electrons and the bromine atom has 8 valence electrons. The two atoms are now ions because their number of protons does not equal their number of electrons. The bromine atom is now a bromide anion and the hydrogen atom is now a hydrogen cation (a proton). The two ions remain together, ionicly bonded and together are called hydrogen bromide.
Boron has 3 valence electrons, and each hydrogen has 1 valence electron. There are two hydrogen atoms in BH2F, so BH2F overall has 3 + 2 = 5 valence electrons.
For neutral atoms, the electron number is always the same as the proton number.For ions, charged atoms, the proton number is different than the electron number by the charge (e.g. a hydrogen ion, H(+1) has 1 proton and 0 electrons, 1 more proton than electrons).
The chemical properties of an atom depend on the number of electrons in its outermost shell, known as the valence electrons. These electrons determine how atoms interact with other atoms to form chemical bonds.
Acetylene (C2H2) has 2 valence electrons for each carbon atom and 1 valence electron for the hydrogen atoms. Therefore, acetylene has a total of 10 valence electrons (4 from carbon and 6 from hydrogen).
The H3O+ ion has three hydrogen atoms bonded to an oxygen atom. Each hydrogen atom contributes 1 valence electron, while the oxygen atom contributes 6 valence electrons. Therefore, the total number of valence electrons in the H3O+ ion is 3 (hydrogen) + 6 (oxygen) = 9 electrons.