I would say that descriptive investigations aren't repeatable because it means that you are only describing something - you ask certain question about something, but do not form a hypothesis at that point yet. So it would be a waste of time to simply ask the same questions over and over again with no hypothesis to prove, which is why these types of investigations cannot be repeated.
Answer:
-179.06 kJ
Explanation:
Let's consider the following balanced reaction.
HCl(g) + NaOH(s) ⟶ NaCl(s) + H₂O(l)
We can calculate the standard enthalpy change for the reaction (ΔH°r) using the following expression.
ΔH°r = 1 mol × ΔH°f(NaCl(s)) + 1 mol × ΔH°f(H₂O(l)) - 1 mol × ΔH°f(HCl(g)) - 1 mol × ΔH°f(NaOH(s))
ΔH°r = 1 mol × (-411.15 kJ/mol) + 1 mol × (-285.83 kJ/mol) - 1 mol × (-92.31 kJ/mol) - 1 mol × (-425.61 kJ/mol)
ΔH°r = -179.06 kJ
Answer:
C. Fe will stay positive and increase in magnitude.
Explanation:
Coulomb's law states that the force of attraction of repulsion between two charged particles is directly proportional to the magnitude of their charges and inversely proportional to the square of the distance of separation between them.
This means that if the size of the charges are large, the force acting on them will be large as well. Also if the distance between the two charges increases the force decreases. However, the force increases when the distance of separation decreases.
Like charges repel, therefore, two negative charges brought together will repel each other, and the distance between the two charges decreases, the force will increase in magnitude. Forces of repulsion are considered positive, therefore, the force, Fe, will stay positive and increase in magnitude.