1. How many moles of H₂ would be required to produce 9.0 grams of water?
The answer would be approximately 0.4495 moles of H₂.
2. What mass of H₂O is formed when excess H₂ reacts with 64 g of O₂?
A mass of 72g H₂O will be formed.
3.How many moles of SnF₂ will be produced along with 48 grams of H₂?
Approximately 23.811 moles of SnF₂ will be produced.
4. How many moles of sodium are required to produce 40. grams of NaOH?
The answer would be approximately 1.000722 moles of sodium.
I could only answer 4 of them so sorry, I had like check over it.
The last 2 were super confusing for me.
The answer is definitely 4. It has fewer electrons. This is because, whenever the electrons are few, they are positive. Positive electrons are anions, while the negative ones are cations. Hope i helped. Have a nice day.
Explanation:
The work is to calculate the molar mass of the solute (adrenaline) from the elevation of the boling point and compare with the mass of the structural formula. If they both are reasonably equal then you conclude that the results are in agreement, else they are not in agreement.
Since, you did not include the structural formula, I can explain the whole procedure to calculate the molar mass from the boiling point elevation, and then you can compare with the mass of the structural formula that only you know.
Determination of the molar mass from the boiling point elevation.
1) With the elevation of the boiling point, which is a colligative property, you can find the molality of the solution, using the formula:
ΔTb = i * Kb * m
Where:
> ΔTb is the increase of the boiling point of ths solvent, i.e. CCl4.
> i van't Hoff constant = 1 (because the solute is non ionic)
> m is the molality of the solution
2) Clearing m you get:
m = ΔTb / Kb
Kb is a datum that you must find in a table of internet (since the statement does not include it).
I found Kb = 5.02 °C/m
Then, m = 0.49°C / (5.02°C/m) = 0.09760956 m
3) With m and the mass of solvent you find the number of moles of solute using the formula:
m = number of moles of solute / kg of solvent
You have the mass of the solvent = 36.0 g = 0.0360 kg, so you can solve for the number of moles of solute:
=> number of moles of solute = m * kg of solvent = 0.09760956 m * 0.036kg = 0.0035139 moles
4) With the nuimber of moles and the mass you find the molar mass:
molar mass = mass in grams / number of moles = 0.64 g / 0.0035139 moles = 182 g/mol <------------- this is the important result
5) Now that you have the molar mass you can compare with the mass of the molecular formula. If they are reasonably equal then you conclude that the <span>molar mass of adrenaline calculated from the boiling point elevation is in agreement with the structural formula</span>
Answer:
Try using Ptable or chemicalaid
Explanation:
Ptable is a great website that shows you a dynamic periodic table. It can show you which elements are Halogens, Alkali metals, transition metals, noble gases, and etc!
Chemicalaid is a nice website to find out more information about specific elements, it also lists every element on the periodic table.
