Answer:
a) 2.01 g
Explanation:
- Na₂CO₃ (s) + 2AgNO₃ (aq) → Ag₂CO₃ (s) + 2NaNO₃
First we <u>convert 0.0302 mol AgNO₃ to Na₂CO₃ moles</u>, in order to <em>calculate how many Na₂CO₃ moles reacted</em>:
- 0.0302 mol AgNO₃ *
= 0.0151 mol Na₂CO₃
So the remaining Na₂CO₃ moles are:
- 0.0340 - 0.0151 = 0.0189 moles Na₂CO₃
Finally we <u>convert Na₂CO₃ moles into grams</u>, using its <em>molar mass</em>:
- 0.0189 moles Na₂CO₃ * 106 g/mol = 2.003 g Na₂CO₃
The closest answer is option a).
Answer:
When liquid water is cooled, it contracts until a temperature of approximately 4 degrees Celsius is reached. After that, it expands slightly until it reaches the freezing point, and then when it freezes it expands by approximately 9%. When water freezes, water molecules form a crystalline structure maintained by hydrogen bonding. Ice is less dense than water because the orientation of hydrogen bonds causes molecules to push farther apart, which lowers the density.
1.75 (moles O2) × 6 (moles H2O) ÷ 9 (moles O2) = 1.17 (moles H2O)
You have to convert moles of O2 into moles of H2O so it's the number of moles you start with (1.75 O2) × the number of moles from the element you want (6 H20), then ÷ by the number of moles that the element that you already have (9 O2).