Question

which statement is true about 22.4 l each of hydrogen, ammonia, and uranium dioxide gas assuming that the temperature and pressure are the same for all of gases?
○ hydrogen gas has the least number of molecules.
○ the gases have the same number of molecules.
○ oxygen gas has the most number of molecules.
○ uranium dioxide gas has the most number of molecules.
question 8
1 pts
when ethane (c₂h₆) burns, it produces carbon dioxide and water:
2c₂h₆ (g) + 7o₂ (g) ⟶ 4co₂ (g) + 6h₂o (l)
how many moles of water will be produced when 8 moles of ethane are burned?
○ 24 moles
○ 48 moles
○ 56 moles
○ 64 moles

Explanation:

Step1: Analyze the stoichiometric ratio

From the balanced chemical equation \(2C_{2}H_{6}(g)+7O_{2}(g)\to4CO_{2}(g)+6H_{2}O(l)\), the ratio of \(C_{2}H_{6}\) to \(H_{2}O\) is \(2:6 = 1:3\).

Step2: Calculate the moles of water

If there are \(n = 8\) moles of \(C_{2}H_{6}\), using the ratio \(\frac{n_{H_{2}O}}{n_{C_{2}H_{6}}}=\frac{3}{1}\), then \(n_{H_{2}O}=3\times n_{C_{2}H_{6}}\). Substitute \(n_{C_{2}H_{6}} = 8\) moles, so \(n_{H_{2}O}=3\times8=24\) moles.

Answer:

24 moles