Part A. Atomic Structure & Nuclear Changes (10 items)

During a science fair, Ava explains a model of the atom where electrons move in fixed orbits around the nucleus, similar to how planets orbit the Sun. Which scientist's model is Ava describing?

• Dalton

• Rutherford

• Bohr

• Thomson

Priya visits a hospital for a medical scan, and the doctor mentions using an isotope called Technetium-99m for the imaging process. Why are isotopes like Technetium-99m useful in medicine?

• They are colorless.

• They are stable.

• They can emit radiation safely in small amounts.

• They are cheaper than medicines.

Emma is learning about elements in her science class. She wants to know which subatomic particle is responsible for determining the chemical behavior of an element. Which one should she focus on?

• Proton

• Neutron

• Electron

• Nucleus

Emma is studying two types of carbon atoms: Carbon-12 and Carbon-14. She wants to know how these two atoms differ. What is the difference between Carbon-12 and Carbon-14?

• Number of protons

• Number of electrons

• Number of neutrons

• Atomic number

Rohan is learning about how electricity is generated in nuclear power plants. Which nuclear process powers these plants?

• Fusion

• Fission

• Combustion

• Radiation absorption

Arjun and Mason are trying to create energy by fusing atoms together in their science lab on Earth. Which best explains why this is much harder for them to achieve than it is in the Sun?

• It requires extremely high temperatures and pressure.

• It happens only in water.

• It uses oxygen.

• It needs sunlight.

Priya is curious about why bananas naturally release small amounts of radiation as they ripen. This is due to the isotope:

• Uranium-235

• Potassium-40

• Iodine-131

• Carbon-12

Hannah is learning about nuclear power plants in her science class. Her teacher asks, "What is the main safety concern regarding nuclear waste?"

• It smells bad

• It remains radioactive for thousands of years

• It explodes easily

• It cannot be buried

Emma is studying the periodic table and notices that the atomic number of nitrogen is 7. What does this tell her?

• It has 7 neutrons.

• It has 7 protons.

• It has 7 electrons and 7 neutrons.

• It has 14 protons.

Aria is curious about how different devices work. She wants to know which of the following devices directly uses nuclear principles in its operation.

• Microwave oven

• PET scan in hospitals

• Gas stove

• Blender