Perception Of Salts Flashcards

1
Q

Explain why it is important that magnesium is in excess

A

To neutrilese all nitric acid so solution only contain magnisium nitrate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Explain titration

A

1.mesure 25 cm3 of naoH solution with pippette and transfer solution to conical flask
2.add 3 drops of phenolphathline
3.add dilute sulphuric acid in burrette and measure initial volume
3.add the acid drop by drop to the alkali in the flask and swirl until colour change
4.mesure final volume of acid used and repeat to obtain concordant result

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Describe how the student can obtain dry crystals of hydrated magnesium nitrate from the mixture at end of reaction (dissolving)

A

1.add excess solid a little at a time in a beaker half filled with sulphuric acid during stiring
2.filter mixture to remove excess solid
3.heat the filtration and evaporate till Crystillastion pint in evaporating basin
4.leave solution to cool and crystallises when crystals formed on glass Rod
5.seprate by filtration and dry between 2 filter paper

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Appaurtas use to add naoh solution

A

Pippette

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Why is is better to use phenolphthalien indicator rather than universal indicator in titration

A

Has only one colour and give sharp end point

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Why we warm acid

A

To increase Rate of reaction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

How will student know when the copper (Ii) oxide is in excess

A

When solid perciptae formed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

How will student know when the crystallisation point reached

A

When crystals formed on glass rod

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Precipitation

A

1.mix 2 solutions,preciptate of nacl2(ex) formed and stir them with glass Rod
2.filter the mixture
3.wash residue by distilled water to remove any soluble substances
4.dry residue between 2 filter paper r drying oven

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Colour of perciptate silver chloride

A

White

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Explain why it is important that magnesium is in excess

A

To neutrlise all nitric acid so solution only contain magnesium nitrate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

State why the student uses an excess of zinc powder

A

To neutrilise all acid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Give the reason for using the white tile

A

To see the colour change clearly at the end poiny

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Colour change of methyl benzene in acid natural alkali

A

Red(acid)
Orange(neutral)
Yellow(alkali)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

State why we filter mixture in dissolving

A

To remove excess solid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Why is it better to use distilled water rather than tap water to wash the solid residue

A

No soluble ions

17
Q

Why leaving solid in warm place is important

A

To evaporated water to dry it