• Congratulations to the Class of 2024 on your results!
    Let us know how you went here
    Got a question about your uni preferences? Ask us here

NSG 2020 questions I got wrong - could someone please walk me through them? (1 Viewer)

SadCeliac

done hsc yay
Joined
Sep 23, 2021
Messages
2,490
Location
Sydney <3
Gender
Male
HSC
2023
Question 8:

Ethanol and methanoic acid will reflux to produce ethyl methanoate (an ester). You should first write out an equation for this

Determine the number of moles of both ethanol and methanoic acid. This can be done by using n = m/MM
n(ethanol) = 3.50g / 46.068 g/mol = 0.07597 mol
n(methanoic acid) = 5.75g / 60.052g/mol = 0.09575 mol
Ethanol is the limiting reagent meaning it gets used up completely.
Therefore, the n(ethyl methanoate) = 0.07597 mol since they are in a 1:1 stoichiometry ratio

Now you can calculate the mass of the product extracted
m(ethyl methanoate) = 0.07597 mol x 74.078 g/mol = 5.63g

However, the mass was found to be 24% of the expected result
So 5.63g x 0.24 = 1.35g
I just went over this - is methanoic acid not HCOOH, which has a mm of 46??
 

synthesisFR

afterhscivemostlybeentrollingdonttakeitsrsly
Joined
Oct 28, 2022
Messages
3,312
Location
Getting deported
Gender
Female
HSC
2028
ud think they woulda returned him by now
Inflammation: Occurs when injured cells release chemokines. This attracts neutrophils and also acts on mast cells, causing them to release histamine. Mast cells alert the body after detecting foreign material, releasing chemical signals and blood is rushed to the area, bringing white blood cells. Dilation of blood vessels and infiltration of inflammatory cells at the site of infection causes heat, pain, redness, swelling, and the acute loss of function. When tissues are damaged, they release histamines which increase permeability of proximal blood vessels and allow WBCs to travel more easily to the site. The purpose of inflammation is to eliminate the cause of injury (the pathogen), clear out necrotic cells from the area of infection, and initiate tissue repair by stimulating the flow of blood to the area. By heating the area, pathogens are subjected to higher temperatures which may deactivate them due to their enzymes, stopping infection. Increased temperature enhances activity of white blood cells.
 

SadCeliac

done hsc yay
Joined
Sep 23, 2021
Messages
2,490
Location
Sydney <3
Gender
Male
HSC
2023
Inflammation: Occurs when injured cells release chemokines. This attracts neutrophils and also acts on mast cells, causing them to release histamine. Mast cells alert the body after detecting foreign material, releasing chemical signals and blood is rushed to the area, bringing white blood cells. Dilation of blood vessels and infiltration of inflammatory cells at the site of infection causes heat, pain, redness, swelling, and the acute loss of function. When tissues are damaged, they release histamines which increase permeability of proximal blood vessels and allow WBCs to travel more easily to the site. The purpose of inflammation is to eliminate the cause of injury (the pathogen), clear out necrotic cells from the area of infection, and initiate tissue repair by stimulating the flow of blood to the area. By heating the area, pathogens are subjected to higher temperatures which may deactivate them due to their enzymes, stopping infection. Increased temperature enhances activity of white blood cells.
can i plagarise this for bio <3
 

Users Who Are Viewing This Thread (Users: 0, Guests: 1)

Top