Answer:
A. N₂(g) + 3H₂(g) -----> 2NH₃ exothermic
B. S(g) + O₂(g) --------> SO₂(g) exothermic
C. 2H₂O(g) --------> 2H₂(g) + O₂(g) endothermic
D. 2F(g) ---------> F₂(g) exothermic
Explanation:
The question says predict not calculate. So you have to use your chemistry knowledge, experience and intuition.
A. N₂(g) + 3H₂(g) -----> 2NH₃ is exothermic because the Haber process gives out energy
B. S(g) + O₂(g) --------> SO₂(g) is exothermic because it is a combustion. The majority, if not all, combustion give out energy.
C. 2H₂O(g) --------> 2H₂(g) + O₂(g) is endothermic because it is the reverse reaction of the combustion of hydrogen. If the reverse reaction is exothermic then the forward reaction is endothermic
D. 2F(g) ---------> F₂(g) is exothermic because the backward reaction is endothermic. Atomisation is always an endothermic reaction so the forward reaction is exothermic
Answer:
0.033 M
Explanation:
Let's consider the neutralization reaction between NaOH and HCl.
NaOH + HCl → NaCl + H₂O
0.4 L of 0.1 M NaOH were used. The reacting moles of NaOH are:
0.4 L × 0.1 mol/L = 0.04 mol
The molar ratio of NaOH to HCl is 1:1. The reacting moles of HCl are 0.04 moles.
0.04 moles of HCl are in 1.2 L. The molarity of HCl is:
M = 0.04 mol / 1.2 L = 0.033 M
A line that stay s straight across the graph
