Year 9 Exam revision MC

During a science class, Avery is examining different elements and wonders what determines the chemical identity of an atom. What should Avery focus on?

• Neutrons

• Protons

• Electrons

• Shells

Scarlett is studying atoms in her science class. She learns that a neutral atom has the same number of electrons as:

• Shells

• Neutrons

• Protons

• Valence electrons

Avery and Maya are studying two samples of the same element, but each sample has atoms with different numbers of neutrons. What do these isotopes have?

• Different protons, same neutrons

• Same protons, different neutrons

• Same neutrons, different electrons

• Same electrons, different protons

When Isla's neutral atom loses an electron during a science experiment, it becomes:

• A cation (positive ion)

• An anion (negative ion)

• A neutron

• A proton

Luna is conducting an experiment in her science class. She observes that when a neutral atom gains an electron, it becomes:

• A proton

• An isotope

• A cation

• An anion

During a science class, Evelyn, Noah, and Priya are discussing which elements from the first 20 in the periodic table have full outer shells. Which three elements are they talking about?

• Helium, Neon, Argon

• Oxygen, Nitrogen, Fluorine

• Lithium, Beryllium, Boron

• Carbon, Sodium, Magnesium

During a science class, Olivia noticed that some elements do not react easily with others because their outer shells are full. These elements with full outer shells are called:

• Halogens

• Noble gases

• Alkali metals

• Transition metals

Benjamin, Aria, and Jackson each have a collection of atoms of the same element. What do all these atoms have in common?

• Same number of electrons

• Same number of protons

• Same mass number

• Same neutron number

Arjun, Harper, and Noah are discussing atoms in their science class. Which of the following statements made by them is FALSE?

• All atoms of the same element have the same number of protons

• All atoms of the same element have the same mass number

• Atoms of different elements differ in proton number

• Isotopes have different neutron numbers

What is the atomic number?

• Total number of particles in the nucleus

• Number of neutrons

• Number of protons

• Number of electrons in an ion