Monday, May 21, 2007
XD posted at 11:09 PM
The coumpound is heated for a sufficient time (about 10 mins)to allow complete decomposition.
The compound is is heated in the hottest part of the non-luminous flame to allow complete decompostion.
Upon strong heating, the compound lumps together. The lump cant be broken down despite the constant shaking. Hence, the heat is not evenly distributed in the compound and which results o an incomplete decompostion. Hence, the mass loss is lesser than expected.
The residue was left to cool for a long period of time before weighing again. The residue might be hygroscopic and absorb moisture from the surrounding. Hence, the mass loss will be lesser than expected.
The styrofoam beaker is supported by the beaker to prevent it from toppling and providing it with insulation.
The mixture is stirred constantly throughout the experiment to ensure even mixing. Hence, the lowest/highest temperature can be measure.
The heating is not conducted in a draught-free environment. Hence, heat is loss to the surrounding. Therefore, temperature change is smaller than expected.
Inconsistent heat loss/gain to the surrounding due to inconsistent stirring. Therefore, temperature change is inconsistent.
Mass of boiling tube and content/g
Mass of empty boiling tube/g
Mass of content/g
Consistency --> plus/minus 0.05g
Mass of weighing beaker and content/g
Mass of empty weighing beaker (after reweighing)/g
Mass of content/g
Final temperature/C
Initial temperature/C
Temperature change/C
Check consistency - delta T/mass --> plus/minus 0.1
Neutralisation use water
Reaction use limiting reagent
Amount of heat absorbed or evolved use the mass of solution (usually acid)
Remember to change kJ to J!
Final answers in 3SF!
Calculated figures in 4SF!
Mass in 3dp!
Temperature in 1dp!
me
Me back in the early 90s. Cool huh?
We are closer than veins itself.
Like what Reza said, This is my people.
These are some random Banglah who begged to take a picture with me.
These are my family in SRJC. Even though none of them is perfect, we make up a perfect family!
schools
Tampines Primary School;
East Spring Secondary School;
Millenia Institute;
Serangoon Junior College;
desires
I bounded by a curse; Never to desire ever again.
hopes
Neither can i hope
interest
I do not understand what you speak of
Monday, May 21, 2007
XD posted at 11:09 PM
The coumpound is heated for a sufficient time (about 10 mins)to allow complete decomposition.
The compound is is heated in the hottest part of the non-luminous flame to allow complete decompostion.
Upon strong heating, the compound lumps together. The lump cant be broken down despite the constant shaking. Hence, the heat is not evenly distributed in the compound and which results o an incomplete decompostion. Hence, the mass loss is lesser than expected.
The residue was left to cool for a long period of time before weighing again. The residue might be hygroscopic and absorb moisture from the surrounding. Hence, the mass loss will be lesser than expected.
The styrofoam beaker is supported by the beaker to prevent it from toppling and providing it with insulation.
The mixture is stirred constantly throughout the experiment to ensure even mixing. Hence, the lowest/highest temperature can be measure.
The heating is not conducted in a draught-free environment. Hence, heat is loss to the surrounding. Therefore, temperature change is smaller than expected.
Inconsistent heat loss/gain to the surrounding due to inconsistent stirring. Therefore, temperature change is inconsistent.
Mass of boiling tube and content/g
Mass of empty boiling tube/g
Mass of content/g
Consistency --> plus/minus 0.05g
Mass of weighing beaker and content/g
Mass of empty weighing beaker (after reweighing)/g
Mass of content/g
Final temperature/C
Initial temperature/C
Temperature change/C
Check consistency - delta T/mass --> plus/minus 0.1
Neutralisation use water
Reaction use limiting reagent
Amount of heat absorbed or evolved use the mass of solution (usually acid)
Remember to change kJ to J!
Final answers in 3SF!
Calculated figures in 4SF!
Mass in 3dp!
Temperature in 1dp!
