Chemistry
What is the difference between physical and chemical change?
A chemical change results in formation of a new substance whereas physical change does not form any new substance.
What does the symbol below represent in a circuit diagram?
Single cell
Which organelle is called the “powerhouse of the cell”?
Mitochondria
What is the protective layer in the stratosphere that absorbs harmful UV rays?
Ozone
What is the name of this element (Na)
Sodium
What is the difference between one point of compression and corresponding on the next compression in a sound wave called?
Wavelength
Which blood vessel carries oxygenated blood from the lungs to the heart?
Pulmonary vein
What is the study of how living things interact with each other and their environment?
Ecology
Why does sugar dissolve faster in hot water than in cold water?
Higher temperatures increase the kinetic energy of water molecules, helping them break down the sugar molecules faster
In a parallel circuit, what happens to the total current when another branch is added?
It increases
Which scientist proposed the theory of natural selection?
Charles Darwin
Which greenhouse gas traps significantly more heat per molecule than CO2?
Methane
What is the common name and formula of the gas that turns limewater milky?
Carbon dioxide (CO2)
A car increases speed from 0 to 20 m/s in 5 seconds. What is its acceleration?
4 m/s²
What is the nitrogen- fixing bacteria in root nodules of legumes called?
Rhizobium
What is the term for the site where waste is buried under the ground in a controlled way to isolate it from the environment, reduce pollution, and manage disposal of solid waste?
Landfill/ sanitary landfill
Why do noble gases not form ions under normal conditions?
As they have a complete valence shell which make them chemically inert
A skydiver reaches a constant speed when gravity balances air resistance. What is this called?
Terminal velocity
In which part of the respiratory system, gaseous exchange takes place?
Alveoli/ Air sacs in the lungs
What is the gradual increase in the concentration of phosphorus, nitrogen, and other plant nutrients in an aging aquatic ecosystem such as a lake?
Eutrophication