Answer:
Explanation:
When the amount of H2O2 is doubled while KI is kept constant, the rate of reaction doubles.
When the amount of KI is doubled and the amount of H2O2 is halved, the rate stays nearly constant.
2H2O2 (aq) → O2(g) + 2H2O (l) ------------- first order kinetics reaction.
Catalysts are KI, FeCl3 only, KCl is not a catalyst. Order: KI < MnO2 < Pb < FeCl3.
H2O2 + I– -> IO– + H2O (Step 1)
H2O2 + IO– -> I– + H2O + O2 (Step 2)
It can be seen that the iodine ion (provided by the KI solution) is a product as well as a reactant.
02(g)2Fe? (aq) + 2 H(a) 2 H 2 Fe3 (aq) H2O2(aq) + 2 Fe,Taq) H02(aq) 2 Fe (aq) 2 H (aq)
Answer: D
Explanation: Even if the audiance did not have a pair of shoes felt uncomfortable or worried not a lot of people would have noticed. If anyone noticed it would only be about 5% of people so that is how I came to the conclision of D.
Answer:
c. 1.5 mol
Explanation:
- Firstly, we need to calculate the no, of moles of 39.0 grams of calcium fluoride.
n = mass / molar mass = (39.0 g) / (78.07 g/mol) = 0.499 mol ≅ 0.5 mol.
- CaF₂ ionized in water as:
<em>CaF₂ → Ca⁺² + 2F⁻.</em>
Every 0.1 mole of CaF₂ is ionized to 3 ions (1 ion of Ca⁺² and 2 ions of F⁻).
<em>So, 0.5 mol of CaF₂ will contain (3 x 0.5 mol = 1.5 mol) of ions.</em>
Thus, the right choice is "c. 1.5 mol".
Answer:
Conducting experiments and using the scientific method.
Explanation:
Scientists (and other people) test hypotheses by conducting experiments. The purpose of an experiment is to determine whether observations of the real world agree with or conflict with the predictions derived from a hypothesis. If they agree, confidence in the hypothesis increases; otherwise, it decreases.