Question

question 3
1 pts
the difference between doing compositional stoichiometry and reaction stoichiometry problems is

the use of stoichiometric mole ratios

the use of the van deemter equation.

the use of the ideal gas law.

the use of the cottrell equation.

question 4
1 pts
consider the reaction:
$ch_4 + 2o_2 \
ightarrow co_2 + 2h_2o$
exactly 14.5 moles of $co_2$ are produced from burning how many moles of $ch_4$ in excess oxygen?

29.0 moles

34.5 moles

65.2 moles

14.5 moles

Explanation:

Question 3

• Compositional stoichiometry deals with the composition of substances (e.g., mass percent, empirical formulas), while reaction stoichiometry involves relationships between reactants and products in a chemical reaction, which uses stoichiometric mole ratios from the balanced equation.
• The Van Deemter equation is related to chromatography, the ideal gas law to gas behavior, and the Cottrell equation to electrochemistry—none relate to the difference between these two stoichiometry types. So the correct option is about stoichiometric mole ratios.

Step1: Identify mole ratio

From the balanced reaction $\ce{CH4 + 2O2 -> CO2 + 2H2O}$, the mole ratio of $\ce{CH4}$ to $\ce{CO2}$ is $1:1$.

Step2: Calculate moles of $\ce{CH4}$

Let $n_{\ce{CH4}}$ be moles of $\ce{CH4}$ and $n_{\ce{CO2}} = 14.5$ mol.
Using the ratio $\frac{n_{\ce{CH4}}}{n_{\ce{CO2}}} = \frac{1}{1}$, so $n_{\ce{CH4}} = n_{\ce{CO2}} = 14.5$ mol.

Answer:

A. the use of stoichiometric mole ratios (Note: Assuming the first option is A, as per the order. If options had labels, use the correct label. Here, the first option is the correct one.)

Question 4