Matter and Materials Flashcards

Flashcards covering key concepts from the Matter and Materials lecture notes for Grade 9 Physical Sciences.

What is matter?

Anything that occupies space and possesses mass.

What is an element?

A pure substance that cannot be broken down into simpler substances by chemical means.

What is the periodic table?

A table of over 110 elements, each represented by symbols.

Name some important elements and their symbols.

Iron (Fe), Lead (Pb), Gold (Au), Copper (Cu), Silver (Ag), Bromine (Br), Zinc (Zn), Iodine (I)

What is a compound?

A pure substance formed by the chemical combination of two or more elements in a fixed ratio by mass.

What does a chemical formula represent?

Shows the ratio of elements present in a compound.

List the key assumptions of John Dalton's atomic theory.

All matter consists of solid indivisible particles called atoms; atoms can neither be created or destroyed; all atoms of the same element are identical; atoms combine in whole number ratios; an atom is the smallest part of an element; compounds are formed when two or more atoms combine.

What were the key conclusions from Sir Ernest Rutherford's experiment?

Most of the volume of the atom is empty space; a small nucleus exists in the centre of the atom; the nucleus is composed of positively charged particles called protons; most of the mass of the atom is concentrated in the nucleus; electrons are constantly moving.

What are protons?

Positively charged particles in the nucleus of an atom.

What are neutrons?

Uncharged particles in the nuclei of an atom.

What are periods on the periodic table?

Horizontal rows on the periodic table representing principle energy levels

What are groups on the periodic table?

Vertical columns on the periodic table containing elements with similar chemical properties.

What are transition elements?

Elements found between Group II and Group III of the periodic table

What are inert gases?

Colourless, odorless gases that are stable elements (Group VIII)

What are the subatomic particles that make up an atom?

Protons, neutrons, and electrons.

What are nucleons?

Protons and neutrons combined together in the nucleus.

What is an orbital?

A space where the probability of finding an electron or an electron pair is the greatest.

What is valency?

The number of electrons that a neutral atom either loses, gains, or shares to acquire a stable electronic structure.

What is ionic charge?

The charge that an atom acquires when it loses or gains electrons.

What is a cation?

A positively charged atom formed when a metal loses valence electrons.

What is an anion?

A negatively charged atom formed when a non-metal gains valence electrons.

What are Lewis dot diagrams?

Diagrams that show the positions of the valence electrons of a particular atom.

What forms molecules?

When non-metal atoms combine and share electrons.

What is a molecule?

The smallest particle of an element or compound that can exist on its own and retain the properties of that element or compound.

What is ionic bonding?

Chemical bonding which involves the transfer of electrons and the formation of ions.

What is the law of conservation of atoms?

In any chemical reaction atoms can neither be created nor destroyed.

Name the diatomic molecules.

H2, N2, O2, Cl2, F2, Br2, and I2.

Describe the test for carbon dioxide.

Bubbling carbon dioxide gas through clear limewater; the solution goes milky.

Describe the test for hydrogen.

2 H2 (g) + O2 (g) 2 H2O (g) + energy (popping sound)

Describe the test for oxygen.

A glowing splint will reignite.

What occurs during covalent bonding?

When non-metal atoms share electron pairs due to their orbitals overlapping.

What is an acid?

A substance containing the element hydrogen, which can be replaced by a metal to form a salt.

What are bases?

Compounds that will neutralize an acid to form a salt and water.

Name three common acids and their chemical formulas.

Hydrochloric acid (HCl), Nitric acid (HNO3), Sulphuric acid (H2SO4)

Name three common bases and their chemical formulas.

Sodium Hydroxide (NaOH), Potassium Hydroxide (KOH), Magnesium Hydroxide (Mg(OH)₂)

What is formed when an acid reacts with a metal?

A salt and hydrogen gas.

What is formed when an acid reacts with a carbonate?

A salt, water, and carbon dioxide gas.

What is formed when an acid reacts with a metal oxide?

A salt and water.

What is formed when an acid reacts with an alkali?

A salt and water.