Answer:
9.94 mL, the volume of ethanol needed
Explanation:
The reaction is:
C₂H₅OH(l) + 3 O₂(g) → 2 CO₂(g) + 3 H₂O(l)
We convert the mass of the formed product to moles:
15 g . 1mol / 44g = 0.341 moles
2 moles of dioxide are produced by 1 mol of ethanol, in order to stoichiometry.
Therefore, 0.341 moles of CO₂ must be produced by (0.341. 1) / 2 = 0.1705 moles of alcohol.
We convert the moles to mass, and then, the mass to volume by the use of density.
0.1705 mol . 46 g / 1 mol = 7.84 g of ethanol
Ethanol density = Ethanol mass /Ethanol volume
Ethanol volume = Ethanol mass /Ethanol density → 7.84 g /0.789 g/mL =
9.94 mL
In order to obtain solid NaCl, the student should do a few steps.
First, he/she should do filtration. Pass the mixture through a filter paper, where all the sand should be filtered out already because they're not dissolved in the solution plus they're too small to pass through the filter paper.
Next, the filtrate should be left with NaCl (aqueous state). To seperate NaCl with the liquid, the student can either do evaporation or crystallization, depending on how pure or fast he/she wants the results to be. Evaporation involves heating the beaker or whatever apparatus under the bunsen burner until all the liquid has evaporated. Then, some white powder should be left, they're NaCl solid. For crystallization, the student should just put the beaker on a room condition environment, and wait. They might have to wait a month or so for the liquid to completely evaporate itself and left with clear and pure NaCl crystals.
Answer:
(A) fossil is the most useful.
It serves as an index fossil. The seashell is a great index fossil because it only appears in the sandstone layer in multiple locations in the same layer of time.
Explanation:
Answer:
It cost Evan $17.70 to send 177 text messages. How many text messages did he send if he spent $19.10?
Explanation:
I cant do this
CH4 : H2O
1 : 2
number of moles of H2O = 1.00 x 2
number of moles of H2O = 2.00mol
mass = number of moles x molar mass
mass of H2O = 2.00 x (1 + 1 + 16)
mass of H2O = 36g
