The apparent effects of the gravity of unseen matter on visible objects
Answer:
Reaction A, B, E and F are exothermic reactions.
Explanation:
Exothermic reactions are defined as the reactions in which energy of reactants is more than the energy of the products. In these reactions, energy is released by the system.
The total enthalpy of the reaction
comes out to be negative.
Endothermic reactions are defined as the reactions in which energy of products is more than the energy of the reactants. In these reactions, energy is absorbed by the system.
The total enthalpy of the reaction
comes out to be positive.
So, from the given option reaction which are exothermic are with negative value
that enthalpy of reaction and those are:
1)
,ΔH = -1203 kJ/mol
2)
,ΔH =-176 kJ/mol
3)
,ΔH = -393.5 kJ/mol
4)
,ΔH =-891 kJ/mol
Answer:
1.
- A) protons and neutrons
- B) electrons
2.
- By changing the number of proton.
Explanation:
Protons and neutrons are located at the center of an atom which is nucleus .
Electrons will orbit around the nucleus .
Http://www.chem4kids.com/files/elem_pertable.html this should help.