Page 286 - Chemistry

i) 1 Mole of MnO 4 reacts with 2.5 moles of S.
∴ Moles of MnO 4 in (h) reacts with 2.5 x moles in (h) of S.
3
∴ 25 cm of S will contain 2.5 x 0.0002907 √1 = 0.0007267 √1

j) 1000 x Answer in (i)
25
1000 x 0.0007267 √½ = 0.029068 M √½
25

k) Answer in (j) ⇒ 5.0g
1 Mole of S = 1 x 5.0
Answer in (j)
= 1 x 5.0
0.029068 √½

= 172.0g √½

H 2X∙2H 2O = 172.0
2(l) + X + 2(18) = 172.0 √1
X + 38 = 172.0
X = 172.0 – 38 √½
= 134.0 √½
Q. 2. a) Observations Inferences
- Colourless vapour condenses on the Hydrated salt / water crystallization√1
-
cooler parts of the test tube /OH
- Moist blue litmus paper remains blue
and red litmus paper remains red.
- White powder.
Any 2 = 1 mk

b) Observations Inferences

Dissolve √½ to form a Soluble salt / substance / compound. √½
colorless√½ solution.

i) Observations Inferences
2+
2+
2+
White precipitate √½ Ca , Mg , Ba
Insoluble√1 in excess 3 = 1 mk
2 = ½ 1 = 0 mk
ii) Observations Inferences

2+
2+
White precipitate √1 Ca , Ba 2 = 1 mk
1 = ½ mk

iii) Observations Inferences
2-
No white precipitate. √1 SO 4 √1 absent

iv) Observations Inferences

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