KBr contains 32.9 % potassium by mass. If 6.40g of Br2 is made to react with 3.60 g of potassium the actual mass of potassium which reacted with Br2 is

Question

KBr contains 32.9 % potassium by mass. If 6.40g of Br2 is made to react with 3.60 g of potassium the actual mass of potassium which reacted with Br2 is (A) 3.14 g (B) l.76g (C) 3.6 g (D) None of these

Tardigrade Admin · Accepted Answer

% of bromine in KBr=100-32.9=67.1 % 67.1 g of bromine react with potassium =32.9 g 6.40 g of bromine react with potassium =((32.9 g)×(6.40 g)/(67.1 g)) =3.138 g =3.14 g

Q. KBr contains 32.9 % potassium by mass. If 6.40g of $B r_{2}$ is made to react with 3.60 g of potassium the actual mass of potassium which reacted with $B r_{2}$ is

3.14 g

l.76g

3.6 g

None of these

$%$ of bromine in $K B r = 100 - 32.9 = 67.1 %$
$67.1 g$ of bromine react with potassium $= 32.9 g$
$6.40 g$ of bromine react with potassium
$= \frac{( 32.9 g ) \times ( 6.40 g )}{( 67.1 g )}$
$= 3.138 g$
$= 3.14 g$

Q. KBr contains 32.9 % potassium by mass. If 6.40g of Br2​ is made to react with 3.60 g of potassium the actual mass of potassium which reacted with Br2​ is