19 An excess of calcium carbonate is added to dilute hydrochloric acid, X. The carbon dioxide gas given off is collected and its volume recorded at regular time intervals.
Line X on the graph shows the results obtained.
The experiment is repeated using dilute hydrochloric acid, Y.
Line Y on the graph shows the results obtained.

Over the last 90 years, scientists have added to the body of evidence supporting the big bang theory. what is the latest piece of evidence discovered in 2014?

Which metal exist in liquid state and can be cut with knife ?

The human eye contains a molecule called 11-cis-retinal that changes shape when struck with light of sufficient energy. the change in shape triggers a series of events that results in an electrical signal being sent to the brain that results in vision. the minimum energy required to change the conformation of 11-cis-retinal within the eye is about 164 kj/mol.