Physics, Chemistry, Maths Forum

Maths & chemistry doubt

Maths & chemistry doubt

by Justin George -
Number of replies: 3

(1)The median AD of triangle ABC is bisected at E,BE meets AC in F then AF:AC

(a)1:3 (b)1:2 (c)3:4(d)1:4

(2)CH3-CH2-CO-18O-CH2-CH3+NAOH

which bond is broken???

In reply to Justin George

Re: Maths & chemistry doubt

by aditya gopi -
answer to question 1>

i do not the exact solution.

but since it is an MCQ i would use extreme case analysis.
that is, i would assume the triangle to be a equilateral triangle.this should hold good becuase the given question does not specify anything.

when i calculated in this way i got 1:3

is the answer correct.

answer question 2>

the bond between the oxygens is broken.
in general the alkoxide group always come out of the ester on hydrolysis.

therefore in this case a sodium salt of the acid and the alcohol with the radioactive oxygen are the products.
In reply to Justin George

Re: Maths & chemistry doubt

by Suvarthi Datta -
(1.) Let the co-ordinates of B,C,A be (0,0),(c,0),(a,b) .
As D is the mid-point of BC , co-ordinates of D is (c/2,0)
As E is the mid-point of AD , co-ordinates of E is [(a/2+c/4),b/2] .

Equation of BE is :

=> y=(2bx)/(c+2a) -----------(1)

Equation of AC is :

=> (a-c)*y = b*(x-c) -------------(2)

Solving (1) & (2) :

=> x=(c+2a)/3

=> y=2b/3

Co-ordinates of F are [(c+2a)/3 , 2b/3]

Let AF:FC = m:1
Using section formula :
=> (m*0+b*1)/(m+1) = 2b/3
=> m = 1/2

=> AF:FC = 1:2
=> AF:AC = 1:3
So answer is 1:3


(2)O-O18 bond is broken . - +
The products are : CH3-CH2-COOH & CH3-CH2-O18Na