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 Page 1


G e n e r a l 	 I n s t r u c t i o n s :
T h i s 	 q u e s t i o n 	 p a p e r 	 h a s 	 8 	 q u e s t i o n s .
W r i t e 	 t h e 	 c o r r e c t 	 s e r i a l 	 n u m b e r 	 o f 	 t h e 	 q u e s t i o n 	 b e f o r e 	 a t t e m p t i n g 	 i t .
D r a w 	 d i a g r a m s 	 w h e r e v e r 	 n e c e s s a r y .
W r i t e 	 a n s w e r s 	 i n 	 n e a t 	 a n d 	 l e g i b l e 	 h a n d w r i t i n g .
1 . 	 C h o o s e 	 t h e 	 c o r r e c t 	 a n s w e r s . 	 ( 5 )
a . 	 T h e 	 f o r m u l a 	 f o r 	 c a l c i u m 	 n i t r a t e 	 i s 	 _ _ _ _ _ _ _ _ _ .
i . 	 C a
2
( N O
3
) 	 i i . 	 C a ( N O
3
)
2
	 i i i . 	 C a ( N O
3
)
3
	 i v . 	 C a
3
( N O
3
)
b . 	 W a l l s 	 o f 	 l a r g e 	 i n t e s t i n e 	 a b s o r b 	 _ _ _ _ _ _ _ _ .
i . 	 c e l l u l o s e 	 i i . 	 d i g e s t e d 	 f o o d 	 i i i . 	 w a t e r 	 i v . 	 o x y g e n
c . 	 A 	 p e r s o n 	 s i t t i n g 	 i n 	 f r o n t 	 o f 	 a 	 r o o m 	 h e a t e r 	 f e e l s 	 h o t . 	 N a m e 	 t h e 	 p r o c e s s 	 b y 	 w h i c h 	 h e a t
i s 	 t r a n s f e r r e d .
i . 	 C o n d u c t i o n 	 i i . 	 C o n v e c t i o n 	 i i i . 	 R a d i a t i o n 	 i v . 	 T r a n s m i s s i o n
d . 	 W h i c h 	 o f 	 t h e 	 f o l l o w i n g 	 i s 	 b a s i c 	 i n 	 n a t u r e ?
i . N a
2
S O
4
	 i i . 	 C a 	 ( O H )
2
	 i i i . 	 C a S O
4
	 i v . 	 N a 	 C l
e . 	 C o n v e c t i o n 	 o c c u r s 	 i n 	 _ _ _ _ _ _ _ _ .
i . 	 s o l i d s 	 i i . 	 l i q u i d s 	 i i i . 	 g a s e s 	 i v . 	 b o t h 	 l i q u i d s 	 a n d 	 g a s e s
2 . 	 C o r r e c t 	 t h e 	 u n d e r l i n e d 	 w o r d s 	 a n d 	 r e w r i t e 	 t h e 	 c o r r e c t 	 s t a t e m e n t s . 	 ( 5 )
a . 	 H e a t 	 f r o m 	 t h e 	 s u n 	 r e a c h e s 	 u s 	 b y 	 c o n v e c t i o n .
b . 	 U p p e r 	 f i x e d 	 p o i n t 	 o n 	 t h e 	 F a h r e n h e i t 	 s c a l e 	 i s 	 3 5 0 ° F .
Page 2


G e n e r a l 	 I n s t r u c t i o n s :
T h i s 	 q u e s t i o n 	 p a p e r 	 h a s 	 8 	 q u e s t i o n s .
W r i t e 	 t h e 	 c o r r e c t 	 s e r i a l 	 n u m b e r 	 o f 	 t h e 	 q u e s t i o n 	 b e f o r e 	 a t t e m p t i n g 	 i t .
D r a w 	 d i a g r a m s 	 w h e r e v e r 	 n e c e s s a r y .
W r i t e 	 a n s w e r s 	 i n 	 n e a t 	 a n d 	 l e g i b l e 	 h a n d w r i t i n g .
1 . 	 C h o o s e 	 t h e 	 c o r r e c t 	 a n s w e r s . 	 ( 5 )
a . 	 T h e 	 f o r m u l a 	 f o r 	 c a l c i u m 	 n i t r a t e 	 i s 	 _ _ _ _ _ _ _ _ _ .
i . 	 C a
2
( N O
3
) 	 i i . 	 C a ( N O
3
)
2
	 i i i . 	 C a ( N O
3
)
3
	 i v . 	 C a
3
( N O
3
)
b . 	 W a l l s 	 o f 	 l a r g e 	 i n t e s t i n e 	 a b s o r b 	 _ _ _ _ _ _ _ _ .
i . 	 c e l l u l o s e 	 i i . 	 d i g e s t e d 	 f o o d 	 i i i . 	 w a t e r 	 i v . 	 o x y g e n
c . 	 A 	 p e r s o n 	 s i t t i n g 	 i n 	 f r o n t 	 o f 	 a 	 r o o m 	 h e a t e r 	 f e e l s 	 h o t . 	 N a m e 	 t h e 	 p r o c e s s 	 b y 	 w h i c h 	 h e a t
i s 	 t r a n s f e r r e d .
i . 	 C o n d u c t i o n 	 i i . 	 C o n v e c t i o n 	 i i i . 	 R a d i a t i o n 	 i v . 	 T r a n s m i s s i o n
d . 	 W h i c h 	 o f 	 t h e 	 f o l l o w i n g 	 i s 	 b a s i c 	 i n 	 n a t u r e ?
i . N a
2
S O
4
	 i i . 	 C a 	 ( O H )
2
	 i i i . 	 C a S O
4
	 i v . 	 N a 	 C l
e . 	 C o n v e c t i o n 	 o c c u r s 	 i n 	 _ _ _ _ _ _ _ _ .
i . 	 s o l i d s 	 i i . 	 l i q u i d s 	 i i i . 	 g a s e s 	 i v . 	 b o t h 	 l i q u i d s 	 a n d 	 g a s e s
2 . 	 C o r r e c t 	 t h e 	 u n d e r l i n e d 	 w o r d s 	 a n d 	 r e w r i t e 	 t h e 	 c o r r e c t 	 s t a t e m e n t s . 	 ( 5 )
a . 	 H e a t 	 f r o m 	 t h e 	 s u n 	 r e a c h e s 	 u s 	 b y 	 c o n v e c t i o n .
b . 	 U p p e r 	 f i x e d 	 p o i n t 	 o n 	 t h e 	 F a h r e n h e i t 	 s c a l e 	 i s 	 3 5 0 ° F .
c . 	 A l u m i n i u m 	 h a s 	 a 	 v a l e n c y 	 o f 	 t w o .
d . 	 T a s a a r , 	 m o o g a 	 a n d 	 k o s a 	 a r e 	 t y p e 	 o f 	 w o o l .
e . 	 P o t a s s i u m 	 h y d r o x i d e 	 a b s o r b s 	 o x y g e n 	 w h e n 	 p u t 	 i n 	 t h e 	 f l a s k 	 f o r 	 e x p e r i m e n t 	 t o 	 s h o w 	 t h a t
c a r b o n 	 d i o x i d e 	 i s 	 n e c e s s a r y 	 f o r 	 p h o t o s y n t h e s i s .
3 . 	 A n s w e r 	 t h e 	 f o l l o w i n g 	 i n 	 b r i e f . 	 ( 6 )
a . 	 W h a t 	 i s 	 t h e 	 a t o m i c i t y 	 o f 	 p h o s p h o r u s ?
b . 	 N a m e 	 t h e 	 p r o c e s s 	 o f 	 w a s h i n g 	 w o o l 	 w i t h 	 d e t e r g e n t 	 t o 	 r e m o v e 	 i m p u r i t i e s .
c . 	 N a m e 	 t h e 	 s t r u c t u r e 	 i n 	 t h e 	 c e l l 	 t h a t 	 h a s 	 c h l o r o p h y l l 	 i n 	 i t .
d . 	 N a m e 	 t h e 	 t y p e 	 o f 	 s o i l 	 r e q u i r e d 	 f o r 	 t h e 	 g r o w t h 	 o f 	 w h e a t .
e . 	 N a m e 	 t h e 	 s o i l 	 w h o s e 	 t e x t u r e 	 i s 	 g r i t t y 	 a n d 	 l o o s e .
f . 	 I d e n t i f y 	 t h e 	 i m a g e 	 o f 	 t h i s 	 p l a n t 	 a n d 	 n a m e 	 i t .
4 . 	 G i v e 	 r e a s o n s 	 f o r 	 e a c h 	 o f 	 t h e 	 f o l l o w i n g 	 s t a t e m e n t s . 	 ( 8 )
a . 	 E l e c t r i c 	 c a b l e s 	 l a i d 	 i n 	 s u m m e r s 	 a r e 	 l e f t 	 l i t t l e 	 l o o s e .
b . 	 N e o n 	 h a s 	 t h e 	 s a m e 	 c h e m i c a l 	 s y m b o l 	 a n d 	 f o r m u l a .
c . 	 V e n u s 	 f l y 	 t r a p 	 i s 	 a n 	 i n s e c t i v o r o u s 	 p l a n t .
d . 	 A i r 	 i s 	 a 	 m i x t u r e .
Page 3


G e n e r a l 	 I n s t r u c t i o n s :
T h i s 	 q u e s t i o n 	 p a p e r 	 h a s 	 8 	 q u e s t i o n s .
W r i t e 	 t h e 	 c o r r e c t 	 s e r i a l 	 n u m b e r 	 o f 	 t h e 	 q u e s t i o n 	 b e f o r e 	 a t t e m p t i n g 	 i t .
D r a w 	 d i a g r a m s 	 w h e r e v e r 	 n e c e s s a r y .
W r i t e 	 a n s w e r s 	 i n 	 n e a t 	 a n d 	 l e g i b l e 	 h a n d w r i t i n g .
1 . 	 C h o o s e 	 t h e 	 c o r r e c t 	 a n s w e r s . 	 ( 5 )
a . 	 T h e 	 f o r m u l a 	 f o r 	 c a l c i u m 	 n i t r a t e 	 i s 	 _ _ _ _ _ _ _ _ _ .
i . 	 C a
2
( N O
3
) 	 i i . 	 C a ( N O
3
)
2
	 i i i . 	 C a ( N O
3
)
3
	 i v . 	 C a
3
( N O
3
)
b . 	 W a l l s 	 o f 	 l a r g e 	 i n t e s t i n e 	 a b s o r b 	 _ _ _ _ _ _ _ _ .
i . 	 c e l l u l o s e 	 i i . 	 d i g e s t e d 	 f o o d 	 i i i . 	 w a t e r 	 i v . 	 o x y g e n
c . 	 A 	 p e r s o n 	 s i t t i n g 	 i n 	 f r o n t 	 o f 	 a 	 r o o m 	 h e a t e r 	 f e e l s 	 h o t . 	 N a m e 	 t h e 	 p r o c e s s 	 b y 	 w h i c h 	 h e a t
i s 	 t r a n s f e r r e d .
i . 	 C o n d u c t i o n 	 i i . 	 C o n v e c t i o n 	 i i i . 	 R a d i a t i o n 	 i v . 	 T r a n s m i s s i o n
d . 	 W h i c h 	 o f 	 t h e 	 f o l l o w i n g 	 i s 	 b a s i c 	 i n 	 n a t u r e ?
i . N a
2
S O
4
	 i i . 	 C a 	 ( O H )
2
	 i i i . 	 C a S O
4
	 i v . 	 N a 	 C l
e . 	 C o n v e c t i o n 	 o c c u r s 	 i n 	 _ _ _ _ _ _ _ _ .
i . 	 s o l i d s 	 i i . 	 l i q u i d s 	 i i i . 	 g a s e s 	 i v . 	 b o t h 	 l i q u i d s 	 a n d 	 g a s e s
2 . 	 C o r r e c t 	 t h e 	 u n d e r l i n e d 	 w o r d s 	 a n d 	 r e w r i t e 	 t h e 	 c o r r e c t 	 s t a t e m e n t s . 	 ( 5 )
a . 	 H e a t 	 f r o m 	 t h e 	 s u n 	 r e a c h e s 	 u s 	 b y 	 c o n v e c t i o n .
b . 	 U p p e r 	 f i x e d 	 p o i n t 	 o n 	 t h e 	 F a h r e n h e i t 	 s c a l e 	 i s 	 3 5 0 ° F .
c . 	 A l u m i n i u m 	 h a s 	 a 	 v a l e n c y 	 o f 	 t w o .
d . 	 T a s a a r , 	 m o o g a 	 a n d 	 k o s a 	 a r e 	 t y p e 	 o f 	 w o o l .
e . 	 P o t a s s i u m 	 h y d r o x i d e 	 a b s o r b s 	 o x y g e n 	 w h e n 	 p u t 	 i n 	 t h e 	 f l a s k 	 f o r 	 e x p e r i m e n t 	 t o 	 s h o w 	 t h a t
c a r b o n 	 d i o x i d e 	 i s 	 n e c e s s a r y 	 f o r 	 p h o t o s y n t h e s i s .
3 . 	 A n s w e r 	 t h e 	 f o l l o w i n g 	 i n 	 b r i e f . 	 ( 6 )
a . 	 W h a t 	 i s 	 t h e 	 a t o m i c i t y 	 o f 	 p h o s p h o r u s ?
b . 	 N a m e 	 t h e 	 p r o c e s s 	 o f 	 w a s h i n g 	 w o o l 	 w i t h 	 d e t e r g e n t 	 t o 	 r e m o v e 	 i m p u r i t i e s .
c . 	 N a m e 	 t h e 	 s t r u c t u r e 	 i n 	 t h e 	 c e l l 	 t h a t 	 h a s 	 c h l o r o p h y l l 	 i n 	 i t .
d . 	 N a m e 	 t h e 	 t y p e 	 o f 	 s o i l 	 r e q u i r e d 	 f o r 	 t h e 	 g r o w t h 	 o f 	 w h e a t .
e . 	 N a m e 	 t h e 	 s o i l 	 w h o s e 	 t e x t u r e 	 i s 	 g r i t t y 	 a n d 	 l o o s e .
f . 	 I d e n t i f y 	 t h e 	 i m a g e 	 o f 	 t h i s 	 p l a n t 	 a n d 	 n a m e 	 i t .
4 . 	 G i v e 	 r e a s o n s 	 f o r 	 e a c h 	 o f 	 t h e 	 f o l l o w i n g 	 s t a t e m e n t s . 	 ( 8 )
a . 	 E l e c t r i c 	 c a b l e s 	 l a i d 	 i n 	 s u m m e r s 	 a r e 	 l e f t 	 l i t t l e 	 l o o s e .
b . 	 N e o n 	 h a s 	 t h e 	 s a m e 	 c h e m i c a l 	 s y m b o l 	 a n d 	 f o r m u l a .
c . 	 V e n u s 	 f l y 	 t r a p 	 i s 	 a n 	 i n s e c t i v o r o u s 	 p l a n t .
d . 	 A i r 	 i s 	 a 	 m i x t u r e .
5 . 	 A n s w e r 	 t h e 	 f o l l o w i n g 	 q u e s t i o n 	 i n 	 5 0 - 6 0 	 w o r d s . 	 ( 1 6 )
a . 	 A 	 s o i l 	 s a m p l e 	 t a k e s 	 3 5 	 m i n u t e s 	 t o 	 p e r c o l a t e 	 7 0 0 	 m l 	 o f 	 w a t e r . 	 C a l c u l a t e 	 t h e 	 r a t e 	 o f
p e r c o l a t i o n 	 o f 	 t h e 	 s o i l 	 s a m p l e .
b . 	 F r o m 	 w h i c h 	 a c i d s 	 a r e 	 t h e s e 	 s a l t s 	 o b t a i n e d 	 – 	 c a r b o n a t e 	 a n d 	 c h l o r i d e ?
c . 	 W h a t 	 h a p p e n s 	 w h e n 	 h y d r o c h l o r i c 	 a c i d 	 r e a c t s 	 w i t h 	 c a l c i u m 	 c a r b o n a t e ? 	 W r i t e 	 t h e 	 c h e m i c a l
r e a c t i o n 	 f o r 	 i t .
d . 	 D i s t i n g u i s h 	 b e t w e e n 	 t h e 	 s i l t 	 a n d 	 s a n d y 	 s o i l .
e . 	 W h a t 	 i s 	 s y m b i o s i s ? 	 E x p l a i n 	 w i t h 	 a 	 s u i t a b l e 	 e x a m p l e .
f . 	 W h a t 	 i s 	 p e r i s t a l s i s ? 	 D o e s 	 i t 	 o c c u r 	 o n l y 	 i n 	 o e s o p h a g u s ?
g . 	 D e s c r i b e 	 t h e 	 p r o c e s s 	 o f 	 r e e l i n g .
h . 	 P , 	 Q , 	 R 	 a n d 	 S 	 a r e 	 a l l 	 v a r i o u s 	 t y p e s 	 o f 	 f i b r e s . 	 T h e 	 f i b r e s 	 P 	 a n d 	 Q 	 a r e 	 o b t a i n e d 	 f r o m 	 a n i m a l s
w h e r e a s 	 t h e 	 f i b r e s 	 R 	 a n d 	 S 	 a r e 	 o b t a i n e d 	 f r o m 	 p l a n t s . 	 T h e 	 y a r n 	 m a d e 	 f r o m 	 P 	 i s 	 u s e d 	 f o r
k n i t t i n g 	 s w e a t e r s 	 w h e r e a s 	 Q 	 i s 	 u s e d 	 f o r 	 w e a v i n g 	 s a r e e s . 	 T h e 	 f i b r e 	 R 	 i s 	 u s e d 	 i n 	 f i l l i n g 	 q u i l t s
a n d 	 S 	 i s 	 u s e d 	 i n 	 m a k i n g 	 g u n n y 	 b a g s . 	 N a m e 	 t h e 	 P , 	 Q , 	 R 	 a n d 	 S 	 f i b r e s .
6 . 	 A n s w e r 	 t h e 	 f o l l o w i n g 	 q u e s t i o n 	 i n 	 8 0 - 8 5 	 w o r d s . 	 ( 2 4 )
a . 	 i . 	 C o n v e r t 	 9 5 ° F 	 t o 	 ° C .
i i . 	 N a m e 	 t h e 	 i n s t r u m e n t 	 u s e d 	 t o 	 m e a s u r e 	 t e m p e r a t u r e .
b . 	 W h y 	 a r e 	 t h e 	 e a r t h w o r m s 	 c o n s i d e r e d 	 t h e 	 f a r m e r ’ s 	 f r i e n d s ? 	 E x p l a i n 	 h o w 	 t r e e s 	 h e l p 	 i n 	 s o i l
f o r m a t i o n 	 a s 	 w e l l 	 a s 	 i n 	 i t s 	 p r o t e c t i o n .
c . 	 R a d h e y s h a y a m 	 a n d 	 D h a n r a j 	 a r e 	 e n j o y i n g 	 a 	 p a r t y . 	 S u d d e n l y , 	 D h a n r a j 	 s u f f e r s 	 f r o m
i n d i g e s t i o n 	 d u e 	 t o 	 a c i d i t y . 	 R a d h e y s h y a m ’ s 	 s i s t e r 	 i m m e d i a t e l y 	 b r i n g s 	 L i m c a 	 f o r 	 h i m .
H e 	 a d v i s e s 	 h i m 	 n o t 	 t o 	 t a k e 	 L i m c a 	 i n 	 t h i s 	 s i t u a t i o n . 	 H e 	 g o e s 	 t o 	 t h e 	 m a r k e t 	 a n d 	 b r i n g s 	 d i g e n e
t a b l e t 	 f o r 	 D h a n r a j .
i . 	 W h y 	 d o e s 	 R a d h e y s h a y a m 	 a d v i s e 	 D h a n r a j 	 n o t 	 t o 	 t a k e 	 L i m c a ?
i i . 	 W h a t 	 v a l u e s 	 d o 	 y o u 	 l e a r n 	 f r o m 	 R a d h e y s h a y a m ?
Page 4


G e n e r a l 	 I n s t r u c t i o n s :
T h i s 	 q u e s t i o n 	 p a p e r 	 h a s 	 8 	 q u e s t i o n s .
W r i t e 	 t h e 	 c o r r e c t 	 s e r i a l 	 n u m b e r 	 o f 	 t h e 	 q u e s t i o n 	 b e f o r e 	 a t t e m p t i n g 	 i t .
D r a w 	 d i a g r a m s 	 w h e r e v e r 	 n e c e s s a r y .
W r i t e 	 a n s w e r s 	 i n 	 n e a t 	 a n d 	 l e g i b l e 	 h a n d w r i t i n g .
1 . 	 C h o o s e 	 t h e 	 c o r r e c t 	 a n s w e r s . 	 ( 5 )
a . 	 T h e 	 f o r m u l a 	 f o r 	 c a l c i u m 	 n i t r a t e 	 i s 	 _ _ _ _ _ _ _ _ _ .
i . 	 C a
2
( N O
3
) 	 i i . 	 C a ( N O
3
)
2
	 i i i . 	 C a ( N O
3
)
3
	 i v . 	 C a
3
( N O
3
)
b . 	 W a l l s 	 o f 	 l a r g e 	 i n t e s t i n e 	 a b s o r b 	 _ _ _ _ _ _ _ _ .
i . 	 c e l l u l o s e 	 i i . 	 d i g e s t e d 	 f o o d 	 i i i . 	 w a t e r 	 i v . 	 o x y g e n
c . 	 A 	 p e r s o n 	 s i t t i n g 	 i n 	 f r o n t 	 o f 	 a 	 r o o m 	 h e a t e r 	 f e e l s 	 h o t . 	 N a m e 	 t h e 	 p r o c e s s 	 b y 	 w h i c h 	 h e a t
i s 	 t r a n s f e r r e d .
i . 	 C o n d u c t i o n 	 i i . 	 C o n v e c t i o n 	 i i i . 	 R a d i a t i o n 	 i v . 	 T r a n s m i s s i o n
d . 	 W h i c h 	 o f 	 t h e 	 f o l l o w i n g 	 i s 	 b a s i c 	 i n 	 n a t u r e ?
i . N a
2
S O
4
	 i i . 	 C a 	 ( O H )
2
	 i i i . 	 C a S O
4
	 i v . 	 N a 	 C l
e . 	 C o n v e c t i o n 	 o c c u r s 	 i n 	 _ _ _ _ _ _ _ _ .
i . 	 s o l i d s 	 i i . 	 l i q u i d s 	 i i i . 	 g a s e s 	 i v . 	 b o t h 	 l i q u i d s 	 a n d 	 g a s e s
2 . 	 C o r r e c t 	 t h e 	 u n d e r l i n e d 	 w o r d s 	 a n d 	 r e w r i t e 	 t h e 	 c o r r e c t 	 s t a t e m e n t s . 	 ( 5 )
a . 	 H e a t 	 f r o m 	 t h e 	 s u n 	 r e a c h e s 	 u s 	 b y 	 c o n v e c t i o n .
b . 	 U p p e r 	 f i x e d 	 p o i n t 	 o n 	 t h e 	 F a h r e n h e i t 	 s c a l e 	 i s 	 3 5 0 ° F .
c . 	 A l u m i n i u m 	 h a s 	 a 	 v a l e n c y 	 o f 	 t w o .
d . 	 T a s a a r , 	 m o o g a 	 a n d 	 k o s a 	 a r e 	 t y p e 	 o f 	 w o o l .
e . 	 P o t a s s i u m 	 h y d r o x i d e 	 a b s o r b s 	 o x y g e n 	 w h e n 	 p u t 	 i n 	 t h e 	 f l a s k 	 f o r 	 e x p e r i m e n t 	 t o 	 s h o w 	 t h a t
c a r b o n 	 d i o x i d e 	 i s 	 n e c e s s a r y 	 f o r 	 p h o t o s y n t h e s i s .
3 . 	 A n s w e r 	 t h e 	 f o l l o w i n g 	 i n 	 b r i e f . 	 ( 6 )
a . 	 W h a t 	 i s 	 t h e 	 a t o m i c i t y 	 o f 	 p h o s p h o r u s ?
b . 	 N a m e 	 t h e 	 p r o c e s s 	 o f 	 w a s h i n g 	 w o o l 	 w i t h 	 d e t e r g e n t 	 t o 	 r e m o v e 	 i m p u r i t i e s .
c . 	 N a m e 	 t h e 	 s t r u c t u r e 	 i n 	 t h e 	 c e l l 	 t h a t 	 h a s 	 c h l o r o p h y l l 	 i n 	 i t .
d . 	 N a m e 	 t h e 	 t y p e 	 o f 	 s o i l 	 r e q u i r e d 	 f o r 	 t h e 	 g r o w t h 	 o f 	 w h e a t .
e . 	 N a m e 	 t h e 	 s o i l 	 w h o s e 	 t e x t u r e 	 i s 	 g r i t t y 	 a n d 	 l o o s e .
f . 	 I d e n t i f y 	 t h e 	 i m a g e 	 o f 	 t h i s 	 p l a n t 	 a n d 	 n a m e 	 i t .
4 . 	 G i v e 	 r e a s o n s 	 f o r 	 e a c h 	 o f 	 t h e 	 f o l l o w i n g 	 s t a t e m e n t s . 	 ( 8 )
a . 	 E l e c t r i c 	 c a b l e s 	 l a i d 	 i n 	 s u m m e r s 	 a r e 	 l e f t 	 l i t t l e 	 l o o s e .
b . 	 N e o n 	 h a s 	 t h e 	 s a m e 	 c h e m i c a l 	 s y m b o l 	 a n d 	 f o r m u l a .
c . 	 V e n u s 	 f l y 	 t r a p 	 i s 	 a n 	 i n s e c t i v o r o u s 	 p l a n t .
d . 	 A i r 	 i s 	 a 	 m i x t u r e .
5 . 	 A n s w e r 	 t h e 	 f o l l o w i n g 	 q u e s t i o n 	 i n 	 5 0 - 6 0 	 w o r d s . 	 ( 1 6 )
a . 	 A 	 s o i l 	 s a m p l e 	 t a k e s 	 3 5 	 m i n u t e s 	 t o 	 p e r c o l a t e 	 7 0 0 	 m l 	 o f 	 w a t e r . 	 C a l c u l a t e 	 t h e 	 r a t e 	 o f
p e r c o l a t i o n 	 o f 	 t h e 	 s o i l 	 s a m p l e .
b . 	 F r o m 	 w h i c h 	 a c i d s 	 a r e 	 t h e s e 	 s a l t s 	 o b t a i n e d 	 – 	 c a r b o n a t e 	 a n d 	 c h l o r i d e ?
c . 	 W h a t 	 h a p p e n s 	 w h e n 	 h y d r o c h l o r i c 	 a c i d 	 r e a c t s 	 w i t h 	 c a l c i u m 	 c a r b o n a t e ? 	 W r i t e 	 t h e 	 c h e m i c a l
r e a c t i o n 	 f o r 	 i t .
d . 	 D i s t i n g u i s h 	 b e t w e e n 	 t h e 	 s i l t 	 a n d 	 s a n d y 	 s o i l .
e . 	 W h a t 	 i s 	 s y m b i o s i s ? 	 E x p l a i n 	 w i t h 	 a 	 s u i t a b l e 	 e x a m p l e .
f . 	 W h a t 	 i s 	 p e r i s t a l s i s ? 	 D o e s 	 i t 	 o c c u r 	 o n l y 	 i n 	 o e s o p h a g u s ?
g . 	 D e s c r i b e 	 t h e 	 p r o c e s s 	 o f 	 r e e l i n g .
h . 	 P , 	 Q , 	 R 	 a n d 	 S 	 a r e 	 a l l 	 v a r i o u s 	 t y p e s 	 o f 	 f i b r e s . 	 T h e 	 f i b r e s 	 P 	 a n d 	 Q 	 a r e 	 o b t a i n e d 	 f r o m 	 a n i m a l s
w h e r e a s 	 t h e 	 f i b r e s 	 R 	 a n d 	 S 	 a r e 	 o b t a i n e d 	 f r o m 	 p l a n t s . 	 T h e 	 y a r n 	 m a d e 	 f r o m 	 P 	 i s 	 u s e d 	 f o r
k n i t t i n g 	 s w e a t e r s 	 w h e r e a s 	 Q 	 i s 	 u s e d 	 f o r 	 w e a v i n g 	 s a r e e s . 	 T h e 	 f i b r e 	 R 	 i s 	 u s e d 	 i n 	 f i l l i n g 	 q u i l t s
a n d 	 S 	 i s 	 u s e d 	 i n 	 m a k i n g 	 g u n n y 	 b a g s . 	 N a m e 	 t h e 	 P , 	 Q , 	 R 	 a n d 	 S 	 f i b r e s .
6 . 	 A n s w e r 	 t h e 	 f o l l o w i n g 	 q u e s t i o n 	 i n 	 8 0 - 8 5 	 w o r d s . 	 ( 2 4 )
a . 	 i . 	 C o n v e r t 	 9 5 ° F 	 t o 	 ° C .
i i . 	 N a m e 	 t h e 	 i n s t r u m e n t 	 u s e d 	 t o 	 m e a s u r e 	 t e m p e r a t u r e .
b . 	 W h y 	 a r e 	 t h e 	 e a r t h w o r m s 	 c o n s i d e r e d 	 t h e 	 f a r m e r ’ s 	 f r i e n d s ? 	 E x p l a i n 	 h o w 	 t r e e s 	 h e l p 	 i n 	 s o i l
f o r m a t i o n 	 a s 	 w e l l 	 a s 	 i n 	 i t s 	 p r o t e c t i o n .
c . 	 R a d h e y s h a y a m 	 a n d 	 D h a n r a j 	 a r e 	 e n j o y i n g 	 a 	 p a r t y . 	 S u d d e n l y , 	 D h a n r a j 	 s u f f e r s 	 f r o m
i n d i g e s t i o n 	 d u e 	 t o 	 a c i d i t y . 	 R a d h e y s h y a m ’ s 	 s i s t e r 	 i m m e d i a t e l y 	 b r i n g s 	 L i m c a 	 f o r 	 h i m .
H e 	 a d v i s e s 	 h i m 	 n o t 	 t o 	 t a k e 	 L i m c a 	 i n 	 t h i s 	 s i t u a t i o n . 	 H e 	 g o e s 	 t o 	 t h e 	 m a r k e t 	 a n d 	 b r i n g s 	 d i g e n e
t a b l e t 	 f o r 	 D h a n r a j .
i . 	 W h y 	 d o e s 	 R a d h e y s h a y a m 	 a d v i s e 	 D h a n r a j 	 n o t 	 t o 	 t a k e 	 L i m c a ?
i i . 	 W h a t 	 v a l u e s 	 d o 	 y o u 	 l e a r n 	 f r o m 	 R a d h e y s h a y a m ?
d . 	 W r i t e 	 t h e 	 c o l o u r 	 c h a n g e 	 t a k e s 	 p l a c e 	 i n 	 a c i d s 	 a n d 	 b a s e s 	 w i t h 	 t h e 	 f o l l o w i n g 	 i n d i c a t o r s :
P h e n o l p h t h a l e i n , 	 t u r m e r i c 	 a n d 	 m e t h y l 	 o r a n g e .
e . 	 E x p l a i n 	 t h e 	 s t e p s 	 t o 	 o b t a i n 	 w o o l l e n 	 y a r n 	 f r o m 	 h a i r 	 o f 	 s h e e p .
f . 	 E x p l a i n 	 t h e 	 d i f f e r e n c e 	 b e t w e e n 	 t h e 	 a t o m 	 a n d 	 t h e 	 m o l e c u l e .
g . 	 W h a t 	 i s 	 t h e 	 f u n c t i o n 	 o f 	 s a l i v a 	 a n d 	 b i l e 	 j u i c e ?
h . 	 D i f f e r e n t i a t e 	 b e t w e e n 	 a u t o t r o p h s 	 a n d 	 s a p r o t r o p h s .
7 . 	 E x p l a i n 	 t h e 	 f o l l o w i n g 	 w i t h 	 t h e 	 h e l p 	 o f 	 w e l l 	 - 	 l a b e l l e d 	 d i a g r a m s . 	 ( 6 )
a . 	 O r g a n s 	 f o r 	 d i g e s t i o n 	 i n 	 h y d r a 	 a n d 	 s p i d e r
b . 	 A 	 t h e r m o s 	 f l a s k 	 m i n i m i z i n g 	 t r a n s f e r 	 o f 	 h e a t 	 b y 	 c o n d u c t i o n , 	 c o n v e c t i o n 	 a n d 	 r a d i a t i o n
8 . 	 A n s w e r 	 t h e 	 f o l l o w i n g 	 q u e s t i o n s 	 i n 	 d e t a i l 	 a n d 	 d r a w 	 w e l l - l a b e l l e d 	 d i a g r a m s 	 w h e r e v e r
r e q u i r e d : 	 ( 2 0 )
a . 	 E x p l a i n 	 h o w 	 d i g e s t e d 	 f o o d 	 i s 	 a b s o r b e d 	 i n t o 	 t h e 	 b l o o d 	 i n 	 h u m a n 	 b e i n g s .
b . 	 M e n t i o n 	 t w o 	 d i f f e r e n c e s 	 b e t w e e n 	 a 	 c l i n i c a l 	 a n d 	 a 	 l a b o r a t o r y 	 t h e r m o m e t e r . 	 W h a t
p r e c a u t i o n s 	 w i l l 	 y o u 	 t a k e 	 w h i l e 	 m e a s u r i n g 	 t e m p e r a t u r e 	 w i t h 	 a 	 l a b o r a t o r y 	 t h e r m o m e t e r ?
c . 	 E x p l a i n 	 w i t h 	 t h e 	 h e l p 	 o f 	 a n 	 e x p e r i m e n t 	 t h a t 	 d a r k 	 c o l o u r e d 	 o b j e c t s 	 a b s o r b 	 a n d 	 l o o s e
r a d i a n t 	 h e a t 	 m o r e 	 q u i c k l y 	 t h a n 	 l i g h t 	 c o l o u r e d 	 o b j e c t s .
d . 	 W h a t 	 i s 	 t h e 	 c o m m o n 	 n a m e 	 f o r 	 c o p p e r 	 s u l p h a t e ? 	 W r i t e 	 i t s 	 f o r m u l a 	 a n d 	 i t s 	 t h r e e 	 u s e s .
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FAQs on Class 7 Science: CBSE Past Year Paper - 8 - Science Class 7

1. What are the different types of natural resources?
Ans. Natural resources can be classified into three main types: renewable resources, non-renewable resources, and flow resources. Renewable resources are those that can be replenished or regenerated naturally, such as sunlight, wind energy, and water. Non-renewable resources, on the other hand, are limited in nature and cannot be replenished once exhausted, like fossil fuels (coal, oil, and natural gas) and minerals. Flow resources are those that are available in a continuous flow and can be used without the fear of depletion, such as wind and tidal energy.
2. What is the role of conservation of natural resources?
Ans. Conservation of natural resources is crucial for the sustainable development of our planet. It involves the responsible and judicious use of resources to ensure their availability for future generations. Conservation helps in preventing the depletion and degradation of natural resources, as well as minimizing the impact on the environment. By conserving resources like water, forests, and wildlife, we can maintain ecological balance, preserve biodiversity, and mitigate the effects of climate change.
3. How can we conserve water resources?
Ans. Water conservation is essential to ensure the availability of clean and freshwater for present and future generations. Here are some ways to conserve water resources: 1. Fix any leaks or drips in taps, pipes, or toilets. 2. Install water-efficient fixtures like low-flow showerheads and dual-flush toilets. 3. Use buckets instead of hoses for washing vehicles or cleaning. 4. Collect rainwater for gardening or household chores. 5. Practice responsible irrigation techniques like drip irrigation or using timers. 6. Avoid overwatering plants and use mulch to retain moisture. 7. Raise awareness about water conservation in your community and encourage others to save water.
4. What are the advantages of using renewable energy sources?
Ans. Renewable energy sources offer several advantages over non-renewable sources like fossil fuels. Here are some of the advantages: 1. Renewable energy sources are abundant and can be replenished naturally, reducing our dependency on finite resources. 2. They produce lower or zero greenhouse gas emissions, contributing to mitigating climate change. 3. Renewable energy technologies are becoming more efficient and cost-effective, making them economically viable. 4. They promote energy independence by reducing reliance on imported fossil fuels. 5. They have the potential to create job opportunities in the renewable energy sector. 6. Renewable energy sources, such as solar and wind, can be harnessed locally, reducing transmission and distribution losses. 7. Using renewable energy sources helps to diversify the energy mix and reduce the environmental impact associated with fossil fuel extraction and combustion.
5. How can we contribute to wildlife conservation?
Ans. Wildlife conservation is crucial to maintain biodiversity and preserve the delicate balance of ecosystems. Here are some ways you can contribute to wildlife conservation: 1. Support conservation organizations and initiatives financially or by volunteering. 2. Spread awareness about the importance of wildlife conservation among family, friends, and the community. 3. Avoid purchasing products derived from endangered species or illegal wildlife trade. 4. Respect wildlife habitats and avoid disturbing or destroying them. 5. Practice responsible tourism by choosing eco-friendly and sustainable options. 6. Plant native trees and create wildlife-friendly gardens or green spaces. 7. Participate in citizen science projects to collect data on wildlife populations and behavior, contributing to scientific research and conservation efforts.
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