Fertiliser Technology
Iron is not used alone as a catalyst in ammonia synthesis, because

It gets oxidised above 500°C
It decomposes ammonia
Its activity declines rapidly, if heated to above 520°C
None of these

ANSWER DOWNLOAD EXAMIANS APP

Fertiliser Technology
Plant tranquillisers

Hold back stem growth and halt plants at a desired height
Produce seedless fruit
Accelerate ripening of food and grain
Cause early maturation of plants

ANSWER DOWNLOAD EXAMIANS APP