This element is a metalloid of Group IV. It has valence electrons on the third energy level. Its name is , symbol. Its atomic number is and its mass number is . This element has neutrons.

4 valence electrons, Silicon, Si, 14, 28.0855, 14

Explanation:

answer: enthalpy

explanation:

for a exothermic reaction, the energy is released i.e. the energy of the products is lower than the energy of the reactants.

= enthaply

= energy of products

= energy of reactants

as , thus comes out to be negative. negative value of enthalpy shows that the reaction is exothermic.

it should be all of them because it asks if you included all of those in your answer

explanation: