IB myp 4-5 Chemistry – Practice Questions- All Topics
Topic :The atmosphere -Emission and Environmental Implications
Topic :The atmosphere- Weightage : 21 %
All Questions for Topic : Characteristics of gases,Atmospheric composition,Testing and Treatment,Extraction,Emission and environmental Implications
Question:
Describe how the salinity level of the lake has changed over the past 100 years. To what extent might the lake have changed naturally over time?
▶️Answer/Explanation
Ans: In 1941, the salinity level in the lake was 48 g l–1. In 1982, at the time when the lake was at its lowest recorded water level, the salinity was 98 g l–1. The natural environment is dynamic, with changes occurring in the salinity levels of the lake as a result of natural phenomena.
Question:
State what types of organisms can be found in the lake.
▶️Answer/Explanation
Ans: Primary lake life including of algae, brine shrimp, and alkali flies, nesting birds including California gulls and snowy plovers, and migratory birds including eared grebes, Wilson’s phalaropes ,
red–necked phalaropes, and 79 other species of water birds.
Question:
Comment on how the diversion of water for an increasing population of Los Angeles has affected the salinity of the lake.
▶️Answer/Explanation
Ans: As an increasing amount of water was diverted from the lake to provide for the increasing Los Angeles population, the volume of the lake decreased, increasing the salinity of the lake.
Question:
What impact has human development and intervention had on the ecosystem of the lake?
▶️Answer/Explanation
Ans: A decrease in the volume of the lake resulted in an increase in the salinity of the lake. As this change was relatively rapid, the ecosystem was unable to adapt at the same rate. Plant and animal species were unable to cope with this rapid change in their environment and the populations began to collapse.