Pt coated with powdered coat of platinum efficient catalyst than only pt metal. Why?
Answers
Answer:
A trapezium has parallel sides 77m & 60 m & its non-parallel sides are 26m & 25 m. Find the area of the trapeziumDraw a line BC parallel to AD
Draw a perpendicular line BE on DF
ABCD is a parallelogram.
BC=AD=25 cm
CD=AB=60 cm
CF=77−CD=17cm
For ΔBCF
semiperimeter of triangle=
2
25+26+17
=
2
68
=34
By Heron's Formula of triangle=
s(s−a)(s−b)(s−c)
=
34(34−25)(34−26)(34−17
)
=204cm²
Also, area of ΔBCF=
2
1
×base×height
204=
2
1
BE×CF
204=
2
1
BE×17
BE=408/17
BE=24 cm
Area of Trapezium=
2
1
(AB+DF)×BE
=1/2(60+77)×24
Area=1644cm²
Answer:
The role of platinum in catalytic converters is to oxidise carbon monoxide (CO) and hydrocar- bons. Platinum is particularly effective at this under oxygen-excessive conditions, so is often the metal of choice for diesel applications.