Answer: The answers are the first and third options.
Answer:- d) 42 kJ of heat is released and the reaction is exothermic.
Solution:- Heat of reaction is the summation of heats of products - reactants.
![\Delta H_r_x_n=\sum [products-reactants]](https://tex.z-dn.net/?f=%5CDelta%20H_r_x_n%3D%5Csum%20%5Bproducts-reactants%5D)
From given information, the energy contained by products is 352 kJ and the energy contained by reactants is 394 kJ. Let's plug in the values in the formula:
= [352 kJ - 394 kJ]
= -42 kJ
Heat of reaction is -42 kJ. The negative sign indicates the heat is released means the reaction is exothermic.
So, the correct option is the last one, 42 kJ of heat is released and the reaction is exothermic.
Answer:
Option D
Explanation:
Rutherford deduced that the atomic nucleus was positively charged because the alpha particles that he fired at the metal foils were positively charged, and like charges repel. Alpha particles consist of two protons and two neutrons, so they are positively charged. In Rutherford's experiments most of the alpha particles passed straight through the foil without being deflected. However, occasionally the alpha particles were deflected in their paths, and rarely the alpha particles were deflected backward at a 180 degree angle.
Since like charges repel, Rutherford concluded that the cause of the deflections of the positively charged alpha particles had to be something within the atom that was also positively charged. Rutherford concluded from his metal foil experiments that most of an atom is empty space with a tiny, dense, positively charged nucleus at the center that contains most of the mass of the atom.
D. The energy released or absorbed during the reaction
Answer:
try hypocenter for the blank spot... hope this helps
Explanation: