Chemistry

Question 1

List the characteristic of a Pure Substance (3)

Answer 1

1) Fixed/Constant Composition
2) Fixed/Constant Properties
3) Cannot be separated by physical means

Question 2

Pure Substances can be further broke up into

Answer 2

Elements and Compounds

Question 2

List the characteristic of Mixtures (3)

Answer 2

1) They have a variable composition
2) Their properties are variable (since components retain their own individual properties)
3) Can be separated by physical mean

Question 3

Mixtures can be broken up into

Answer 3

Homogenous and Heterogenous mixtures

Question 4

How can you determine if a substance is pure ?

Answer 4

It has a fixed melting and boiling point as any impurities will lower its melting and boiling point.

Question 5

An atom is…?

Answer 5

The smallest indivisible particle of an element.

Question 6

An Element is…?

Answer 6

The simplest form of matter

Question 7

Compounds are … ?

Answer 7

composed of more than one type or kind of atom, which are combined chemically.

Question 8

What is a homogenous mixture

Answer 8

A mixture in which the properties and composition are uniform throughout the mixture (the components cannot be distinguished from each other)

Question 9

Examples of Homogeneous Mixtures

Answer 9

1) Air
2) Salt Dissolved in water
3) Metal Alloy such as brass (mix of zinc and copper)

Question 10

What is a Heterogeneous Mixture ?

Answer 10

Non-uniform mixture whose components are in different states and can be distinguished from each other such as Suspensions and Colloids

Question 11

Examples of Heterogeneous Mixtures

Answer 11

salt and sand, mayonnaise and muddy water

Question 12

What is Chromatography

Answer 12

Used to separate colors and parts of a substance

Question 13

What is a Saturated Solution

Answer 13

Contains as much solute as can be dissolved at a particular temperature in the presence of undissolved solute.
No more solute can dissolve in the solvent at that temperature

Question 14

What is a Solution

Answer 14

A homogeneous mixture formed when a solute is dissolved in a solvent

Question 15

What is a Solute

Answer 15

The substance that is bein dissolved (is in the smaller amount)

Question 16

What is solvent

Answer 16

Does the dissolving (is in the greater amount)

Question 17

List of separation techniques

Answer 17

1) Filtration
2) Evaporation / Recrystallization
3) Simple Distillation
4) Sublimation
5) Fractional Distillation
6) Separating Funnell

Question 18

What is a Immiscible Liquid

Answer 18

Liquids which do not mix (oil and water)

Question 19

What is an Isotope

Answer 19

a variation of an element that possesses the same atomic number but a different mass number
E.g: Carbon 12 and Carbon 14 (both have 6) but Carbon 14 has 8 neutrons

Question 20

Mass and Atomic number of: Hydrogen

Answer 20

mass number: 1
Atomic Number: 1

Question 21

Mass and Atomic number of: Helium

Answer 21

Mass number: 4
Atomic number: 2

Question 22

Mass and Atomic number of: Lithium

Answer 22

Mass number: 6.9 or 7
Atomic number: 3

Question 23

Mass and Atomic number of: Beryllium

Answer 23

Mass number: 9
Atomic number: 4