Structure 1.1 Introduction to Particulate Nature of Matter

Question 1

Pure substances are? Explain.

Answer 1

1. Elements - pure chemical substance composed of atoms with the same number of protons in atomic nucleus - cannot be broken down into simpler substance
2. Compounds - substance made by chemically combining two or more elements in a fixed ratio - physical + chemical properties are different from its constituent elements

Question 2

What types of mixtures exist? Explain both

Answer 2

1. Homogenous - has uniform composition with a fixed ratio - cannot see components
2. Heterogeneous - Non-uniform composition and properties are not the same throughout - can usually separate

Question 3

3 Methods to separate and explain

Answer 3

1. Filtration - solid is separated from a liquid/gas by means of a membrane
2. Distillation - separating solvent from solute
3. Paper chromatography - separate coloured chemicals

Question 4

What are solids?

Answer 4

-particles closely packed
-strong IP forces vibrate in position (vibrate until have enough energy to break away
-fixed shape and volume, do not move freely
-low KE

Question 5

What are liquids?

Answer 5

-spread out
-weak IP forces
-no fixed volume or shape
-medium to high KE

Question 6

What are gases?

Answer 6

-fully spread out
-negligible IP forces
-move freely
-no fixed volume/shape
-high KE

Question 7

What is plasma?

Answer 7

-state of matter
-only at very high how temperatures - fire

Question 8

What are the elements of the Kinetic Molecular Theory?

Answer 8

-Explains difference in physical properties of states of matter
-distinguishes states by modes of particle movement
-increase in temp = increase in KE
-state of matter determined by temperature/pressure

Question 9

Solid - gas? and other way
solid - liquid? and other way
liquid - gas? and other way

Answer 9

1. Sublimation/deposition
2. melting/freezing
3. vaporization (boiling/evaporation)/condensation

Question 10

Fluids are… and use…

Answer 10

Liquids/gases
Diffusion - particles spread out evenly due to random movements - particles with smaller matter diffuse quicker

Question 11

Explain why external pressure affects boiling point

Answer 11

pressure environmentally changes, therefore the pressure changes. With this change, water’s boiling point become positively correlated - meaning that as pressure increases boiling point increases, as pressure decreases, boiling point decreases.

Question 12

In a temperature/energy graph regarding kinetic energy and the states of matter, explain at what points the temperature and pressure increases and why

Answer 12

As the substance is heated at one state of matter, the temp, pressure and KE increases. This is because the particles are using the heat energy to then separate during its state change.

Question 13

In a temperature/energy graph regarding kinetic energy and the states of matter, explain why and at which points the line will plateau

Answer 13

The line plateaus as the substance changes states. It is not increasing in temp, pressure, or energy because instead the particles are using the absorbed energy to break IP forces to become a different state.

Question 14

Melting and boiling are considered… because they…

Answer 14

endothermic, require energy to seperate

Question 15

Freezing and condensation are considered… because they…

Answer 15

exothermic, release energy as they form bonds and bring particles closer together.

Question 16

What is a Kelvin and how to convert to C?

Answer 16

Is the absolute zero, unit of temperature, no movement, average KE particles, add degrees and 273.15 to get K.