Q.

Read the passage carefully and answer the following questions from (i) to (v):

 

Marble’s popularity began in ancient Rome and Greece, where white and off-white marble were used to construct a variety of structures, from hand-held sculptures to massive pillars and buildings.

(ii) A student added 10 g of calcium carbonate in a rigid container, secured it tightly and started to heat it. After some time, an increase in pressure was observed, the pressure reading was then noted at intervals of 5 mins and plotted against time, in a graph as shown. During which time interval did maximum decomposition take place

1 15–20 min  
2 10–15 min  
3 5–10 min  
4 0–5 min  

Ans.

(4)