Electrons in Atoms and the Periodic Table
Chemical Bonds
The impact of Humans on Natural Environments
Living Organisms: Variety and Common Features
Waves and Electromagnetic Radiation
100

What is the name of the rule that states no two electrons in an atom can have the same spin number?

Pauli Exclusion Principle

100

What is the name of the ion of Fe that loses 3 electrons?

Iron (III) ion

100

What are the two main components of an ecosystem?

Biotic (living) and abiotic (non-living) components.

100

What are the three main parts of most cells?

Cell membrane, cytoplasm, nucleus

100

What are the two classes of waves?

Mechanical and electromagnetic waves

200

What is the principal quantum number?  

(n)

200

Name the compound Cu(NO₃)₂

Copper(II) nitrate

200

What process returns nitrogen gas to the atmosphere?  

Denitrification

200

What is diffusion?

The movement of particles from an area of high concentration to low concentration.

200

What is the difference between a transverse and a longitudinal wave?

In transverse waves, particles move perpendicular to the direction of the wave; in longitudinal waves, they move parallel.


300

What is the energy needed to remove an electron called?

Ionization energy

300

Why do ionic compounds conduct electricity when dissolved in water?

Because the ions are free to move and carry electric current.

300

What factors affect population size?

irth rate, death rate, immigration, emigration

300

What is active transport and how is it different from diffusion?

Active transport moves substances against a concentration gradient using energy.

300

Define wavelength and include its SI unit.

The distance between two consecutive crests or troughs in a wave. The SI unit is m-meters.

400

It forms at extremely low temperatures close to absolute zero; it helps scientists study quantum mechanics.

Bose-Einstein condensate 

400

What are two properties typical of covalent compounds?

Low melting/boiling points and poor conductivity.

400

What is eutrophication, and what causes it?

Overgrowth of algae due to excess nutrients from fertilizers.

400

Why is the nucleus considered the control center of the cell?

It contains DNA that controls cell activities.

400

What formula relates wave speed, frequency, and wavelength?

Wave speed = frequency × wavelength (v = f × λ)

500

A radioactive isotope undergoes alpha decay. What happens to its atomic number and mass number?


The atomic number decreases by 2, and the mass number decreases by 4.

500

Explain the difference between a polar bond and a polar molecule.

A polar bond has uneven electron sharing; a polar molecule has an overall dipole due to bond shape and polarity.

500

Why are food webs more accurate than food chains in showing feeding relationships?

Because they show multiple pathways and interconnections in an ecosystem.

500

What process connects the nucleus, RER and the Golgi body? 

Protein synthesis 

500

Why does a straw in water appear bent?

Because of refraction — light changes speed and direction in different media.