Calculate number of electron present in `9.5" g of" PO_(4)^(3-)`:
(a) 6
(b) `5N_(A)`
(c) `0.1N_(A)`
(d) `4.7N_(A)`

If n=2^3xx3^4xx5^4xx7 , then the number of consecutive zeros in n , where n is a natural number, is (a) 2 (b) 3 (c) 4 (d) 7

If 2(2n+5)=3\ (3n-10), then n= (a)5 (b) 3 (c)7 (d) 8

If in the expansion of (a-2b)^(n) , the sum of 5^(th) and 6^(th) terms is 0, then the values of a/b is (a) (n-4)/(5) (b) (2(n-4))/(5) (c) (5)/(n-4) (d) (5)/(2(n-4))

If the mean of first n natural numbers is (5n)/9 , then n= (a) 5 (b) 4 (c) 9 (d) 10

In an organic compound of molar mass 108 g mol^(-1) , H and N atoms are present in 9 : 1 : 3.5 by weight. Molecular formula can be: "1.C_(6)H_(8)N_(2) " 2.C_(7)H_(10)N 3.C_(5)H_(6)N_(3) 4.C_(4)H_(18)N_(3)

The value of sum_(n=3)^(oo)(1)/(n^(5) - 5n^(3) +4 n) is equal to - (a) (1)/(120) (b) (1 )/(96) (c) (1)/(24) (d) (1)/(144)

If two events A and B are such that P(A^c)=0. 3. P(B)=0. 4 a n d P(AnnB^c)=0. 5 , t h e n P(B/(AuuB^c))= (a) 0. 9 (b). 0. 5 (c). 0. 6 (d). 0. 25

Lt_(ntooo) sum_(r=1)^(6n) 1/(n+r)= (A) log6 (B) log7 (C) log5 (D) 0

Assign the position of the element having outer electronic configuration a. ns^(2)np^(4) for n=3 b. (n-1)d^(2)ns^2 for n=4 and c. (n-2) f^(7)(n-1)d^(1)ns^(2) for n=6 , in the periodic table.

Which pair of points lies on the same side of 3x-8y-7=0? a) (0,-1)a n d(0,0) b) (4, -3) and (0, 1) c) (-3,-4)a n d(1,2) d) (-1,-1)a n d(3,7)