Year 8 Chemistry CAT 1 Review Flashcards

Flashcards to review key concepts from the Year 8 Chemistry CAT 1 exam, covering elements, compounds, atoms, chemical reactions, and the periodic table.

How is an element symbol correctly written?

With the first letter capitalized (e.g., Na)

What is a key feature of element symbols?

They mostly contain one or two letters.

How can tap water best be described in chemistry?

A mixture

What is true about CO2 in terms of elements and compounds?

It is a compound but not an element.

Given that bromine is the only non-metal liquid at room temperature, which group could bromine belong to?

Group W or Y

Which of the following is an example of a physical change?

Melting chocolate

What does the atomic number of an element represent?

The number of protons in the nucleus

Which statement is true about the arrangement of elements in the periodic table?

Li and K are in the same group and share similar properties.

Which of the following is NOT an example of a chemical change?

Mixing blue and red paint to obtain purple paint.

What chemical formula represents acetaldehyde?

C2H4O

Draw and label a molecule of O2

Two oxygen atoms bonded together.

Draw and label a molecule of NH3.

One nitrogen atom bonded to three hydrogen atoms.

What is the chemical formula for a molecule with three carbon atoms and eight hydrogen atoms?

C3H8

Describe the structure of an atom.

In the nucleus there are protons and neutrons, and outside is electrons.

How are elements arranged on the periodic table?

Elements on the periodic table are arranged from there the protons in the nucleus

What is an element?

A substance made of only one type of atom.

What is an atom?

The smallest building blocks of matter.

What is a compound?

A substance consisting of two or more types of atoms.

What is a mixture?

A combination of two or more elements or compounds.

What is a molecule?

A cluster of atoms bonded together.

Identify the element with the symbol 'B'.

Boron

Identify the element with the symbol 'Be'.

Beryllium

Identify the element with the symbol 'Li'.

Lithium

Identify the element with the symbol 'K'.

Potassium

What is the chemical symbol for hydrogen?

H

What is the chemical symbol for chlorine?

Cl

What is the chemical symbol for sodium?

Na

What is the chemical symbol for neon?

Ne

What elements are in ammonia (NH3) and how many atoms of each are there?

Nitrogen = 1, Hydrogen = 3

What elements are in methane (CH4) and how many atoms of each are there?

Carbon = 1, Hydrogen = 4

What elements are in sodium chloride (NaCl) and how many atoms of each are there?

Sodium = 1, Chlorine = 1

What elements are in calcium carbonate (CaCO3) and how many atoms of each are there?

Calcium = 1, Carbon = 1, Oxygen = 3

What elements are in sulfuric acid (H2SO4) and how many atoms of each are there?

Hydrogen = 2, Sulfur = 1, Oxygen = 4

What elements are in sodium bicarbonate (NaHCO3) and how many atoms of each are there?

Sodium = 1, Hydrogen = 1, Carbon = 1, Oxygen = 3

Identify which shapes represent elements.

A and E

Identify which shapes represent compounds.

B

Identify which shapes represent mixtures.

C

Why can elements and compounds be represented by chemical formulas while mixtures cannot?

Elements & compounds are bonded together and that's why they can be represented by chemical formulas while mixtures cannot because mixtures are mixed together meaning they are not bonded.

List three properties of metals

Malleable, has luster, and is conductive

Describe if the change is chemical of physical and the evidence when a teaspoon of sugar is added to a glass of water.

Physical change occurs because it can be reversed, you can dehydrate the water to get sugar.

When potassium iodide solution is added to lead nitrate solution, a yellow solid of lead iodide as well as a solution of potassium nitrate are formed. Is that a chemical change or physical change?

This is a physical change because you can't change it or turned it back to its original form

When potassium iodide solution is added to lead nitrate solution and a yellow solid of lead iodide as well as a solution of potassium nitrate are formed. identify the reactants in this change.

Potassium iodide + lead nitrate

When potassium iodide solution is added to lead nitrate solution and a yellow solid of lead iodide as well as a solution of potassium nitrate are formed. Identify the products in this change.

Lead Iodide + Potassium Nitrate

When potassium iodide solution is added to lead nitrate solution and a yellow solid of lead iodide as well as a solution of potassium nitrate are formed. Write a word equation to show this change.

Potassium iodide added to lead nitrate reacts to make lead iodide + Potassium Nitrate

Explain the independent variable in the experiment with magnesium strips and hydrochloric acid.

The length of the magnesium strip

Explain the dependent variable in the experiment with magnesium strips and hydrochloric acid.

Changing how much magnesium strip changes temperature

Explain the aim of the experiment with magnesium strips and hydrochloric acid.

To investigate to see how much Mg strips are required to reach 41.5 ° C.

Write a hypothesis for the experiment with magnesium strips and hydrochloric acid.

It is hypothesised that when you add more strips of Magnesium the temperature will go higher depending on how much pair My & you add.

When graphing results of length of magnesium against the temperature of the solution, state the trends shown.

Increasing length of Magnesium increases temerature in the solution.