Page 270 - Chemistry

H
C
H 3C OH CH 3
42 42
n = 118  1
+
35. i) RCOONa Soapy detergent
+
R CH 2 OSO 3 Na soap less detergent
+
ii) RCH 2OSO 3 Na does not form scum. Its calcium and magnesium salts are soluble
iii) Chlorine bleaches by oxidation
SO 2 bleaches by reduction

36. (a) Polyphenylethene
(b) H H

C C

H



Radioactivity

1. u= 234 √ V = 91√

2. (a) Nuclear fusion is a process whereby smaller nuclei combine to form a larger one at high
temperatures;
Nuclear fission is whereby a large nuclide splits to form smaller one when hit by a neutron

(b) 230 230 4

90 91 2

3. 238 234 4
U Y + H e √1 (1 mk)
92 90 2
2
234 234 0
Y Z + e √1 (1 mk)
90 91 -1

4. (a) Is an atom or atomic nucleus characterized by its atomic number and mass number

(b) 14 = 7 1 from the graph
2 1
half –life is 10days
1
(c) Destroys physical properties of metals e.g. lower tensile strength
1

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