Answer:
C) Covalent bonds come about because of a sharing of electrons; ionic bonds do not.
Explanation:
There are two main types of chemical bonds- covalent and ionic/electrovalent bonds.
Ionic bond: Ionic or electrovalent bonds are characterized by the transfer of electrons from electropositive atoms (metals) to electronegative atoms (non-metals). The metal atoms after donating their electrons become positively charged ions (cations) while the non-metal atoms after accepting electrons become negatively charged ions (anions). Strong electrostatic forces of attraction constitutes ionic bonds.
Covalent bond: Covalent bonds are formed by the sharing of electrons by the atoms involved in the bond; usually between atoms of comparable electronegativities or atoms of the same element. The shared electrons are contributed by each of the atoms involved in the bonding or may be contributed by only one of the atoms. In covalent bonding, molecules rather than ions are formed.
Answer:
Los metaloides serían los elementos con propiedades intermedias. No existe una definición estandarizada de elemento metaloide ni un consenso completo sobre los elementos que son metaloides. A pesar de la falta de especificidad en el término, es muy utilizado en los textos químicos, tanto educativos como divulgativos o de investigación.
Explanation:
Using E=hν where h is Planck's constant and v is the frequency of the photon. In the question above,the wavelenght is given so we can find the frequency of the photon using c=λν. c is a constant =3*10^8 so frequency is equal to
(3*10^8)/0.135*10^-9. Then use ur frequency in the eqn above using h 6.626*10^-34