<span>The scientific method is a systematic way of questioning about the world around us and answering questions. The number of steps varies from one description to another, mainly when data and analysis are separated into separate step, but this is a fairly standard list of 6 scientific method steps, which you are expected to know for any science class:
1. Form a Hypothesis. This is a sort of educated guess about what you expect.
2. Design an Experiment to test your hypothesis. An experiment has an independent and dependent variable. You change or control the independent variable and record the effect it has on the dependent variable.
3. Conduct Experiment
4. Record data and observations and analyze what the data means. Often, you'll prepare a table or graph of the data.
5. Form a Conclusion. Conclude whether to accept or reject your hypothesis. Communicate your results.</span>
Answer:
See explanation and images attached
Explanation:
a) In the mechanism for the acid catalysed esterification of propanoic acid using ethanol, we can see that the first step is the protonation of the acid followed by nucleophillic attack of the alcohol. Loss of water and consequent deprotonation regenerates the acid catalyst. We can see the fate of the 18O labelled ethanol in the mechanism shown.
b) In the second mechanism, an unnamed ester is hydrolysed using an acid catalyst. The attack of the acid and subsequent nucleophillic attack of water labelled with 18O leads to the incorporation of this 18O into the product acid as shown in the mechanism attached to this answer.
The law of conservation of mass states that mass is neither created nor destroyed. Since we have 2 g/mol of A and 3 g/mol of B then AB should be equal to the sum of their molar mass that is
2 g/mol + 3 g/mol = 5 g/mol AB
for the case of A2B3
A2 = 2 * 2 = 4 g/mol
B3 = 3 * 3 = 9 g/mol
therefore A2B3 = 13 g/mol
Less friction to stop the wheel from turning
Answer:

Explanation:
The equation for mass is:

We plug in the given values into the equation:

