2.0 how matter observations change

Question 0

Iron Age

Answer 0

Eventually people learned to combine iron with carbon to produce an even harder material- steel. They used steel to make blades for hunting and for armour

Question 1

Use of gold B.C

Answer 1

Gold and copper became highly valued because of their properties of lustre, colour and the ability to not tarnish. Copper was made into wire whereas gold was made into sheets and jewellery

Question 2

Greek philosophers

Answer 2

Idea that all matter is made up of particles

They observed that a rock could be broken down into powder: making the idea of divisible substances

Question 3

Democritus

Answer 3

A Greek philosopher who used the word atomos to discribe the smallest particles that could not be broken further. Atomos means indivisible!
Democritus believed that these particles he discovered gave each material its own set of properties

Question 4

Alchemy/ alchemists

Answer 4

Are people who were part magician and part scientist
The alchemy comes from the Arabic word alkimiya which translates as “the chemist”
Today the study of alchemy is called pseudo-science(not real science because it includes magic)
They believed that is was possible to change metals into gold
They created useful tools that are still found in labs today such as plaster

Question 5

Al-Razi

Answer 5

Arab alchemist who discovered what we now call plaster in Paris

Question 6

John Dalton

Answer 6

English scientist used his own experience to develop a theory of the composition of matter.
Dalton suggested that they were made up of elements. He was the first to define an element as a pure substance. He states that an element is currently nooses if a particle called an atom

Question 7

Billiard ball model

Answer 7

Created by John dalton to show his theory that atoms are like solids. The atoms of each element have a different made than atoms of other elements

Question 8

J.J Thomson

Answer 8

The first British physicist to discover a subatomic particle (smaller than an atom) he also experimented with cathode rays, concluded that the Rays were made of streams of negatively charged particles. He also discovered electrons

Question 9

Electrons

Answer 9

Particles that are much smaller in mass than even a hydrogen atom and are made into rays of negatively charged particles.

Question 10

Cathode rays

Answer 10

Produced when a piece of metal is heated at one end of the tube containing a gas. That heated metals sends out a stream of electrons toward the opposite end of the tube, causing the end of the tube to glow. Cathode ray tube’s are now used in electrical devices such as televisions.

Question 11

The raisin bun model

Answer 11

Created by Thompson, he described the atom as a positively charged sphere in which negatively charged electrons were embedded like raisins in a bun.( A circle with negative signs and positive signs)

Question 12

Hantaro Nagoka model

Answer 12

This Japanese physicist refined the model of the atom further. In this model the atom resembled a miniature solar system. In the center of the atom was a large positive charge. The negatively charged electrons orbiting around the positive charge like planets orbiting around the sun.

Question 13

Niels Bohr

Answer 13

A danish researcher who worked with Rutherford, suggested that electrons do not orbit randomly in an atom. Bohr said that they move in a specific circular orbits, or electron shells, as shown in his model. For this work he won the Nobel Prize in physics in 1922

Question 14

Neutron

Answer 14

Has about the same mass as a proton but carries no electrical charge.

Question 15

Electron

Answer 15

Has only a very small mass of either a proton or neutron

Question 16

Jons Jacob Berzelius

Answer 16

Modified Deltons symbols and suggested using letters rather than pictures to represent an element. The first letter capitalized of an element would become the symbol. For elements with the same first letter, such as hydrogen and helium, a small second letter would be added. We still use this method today to identify elements.

Question 17

Atomic mass

Answer 17

The mass of one atom of an element. Scientists were able to describe and determine the average mass of an atom of other elements by comparing it with the mass of a Carbon atom bracket. Atomic mass is measured by atomic mass unit of amu.

Question 18

John newlands

Answer 18

Recognized a pattern when elements were listed by increasing atomic mass. He noticed that properties of elements seemed to repeat through this list at regular intervals. He called this pattern the law of octaves, as the pattern was similar to the octave scale on piano.

Question 19

Dmitri Mendeleev

Answer 19

Was able to organize the elements in a way that reflected the pattern in the properties of the elements. He collected the 63 elements known to exist in his time. These included lithium,carbon, nitrogen, oxygen, fluorine, sodium, silicon, phosphorus, sulphur and chlorine. He wrote down the properties of each element using it’s melting point, density and color. Using the properties he would sort them into patterns like playing a card game. Mendeleev noticed gaps in his chart so he predicted the possible atomic mass in elements to fit the gaps.

Question 20

Periodic table of elements

Answer 20

Created by Dimitri Mendeleev and it included the 63 known elements of his time. Sense then more elements have been discovered.

Question 21

Period

Answer 21

A horizontal row. As you move from left to right across the period the properties of the elements change. From left to right the elements gradually change from metals to non-metals. The most reactive metals start on the left.

Question 22

Groups or families

Answer 22

Vertical columns. Groups are usually referred to by the first element in the column. The other metals in that column have properties similar to those of the first.

Question 23

Atomic number

Answer 23

The number above the elements symbol on the left is the atomic number. It shows how many protons are in the nucleus of one atom of that element. Because atoms are neutral, the number of protons equals the number of electrons. Therefore the atomic number also tells you how many electrons and protons are in that particular element.

Question 24

Ion charge

Answer 24

The positive and negative signs in the top right corner of the box in the periodic table.

Question 25

Metals

Answer 25

Are shiny, malleable and ductile. They also conduct electricity!

Question 26

Non-metals

Answer 26

Can be solid or gas. Solid non-metals are doll, riddle elements. Non-metals except carbon do not conduct electricity.

Question 27

Insulators

Answer 27

Non-metals that do not conduct electricity

Question 28

Metalloids

Answer 28

Have both metallic and non-metallic properties

Question 29

Alkali metals

Answer 29

Group 1 elements, not including hydrogen are called alkali metals. These metals are the most reactive metals, reacting when exposed to air or water

Question 30

Alkali earth metals

Answer 30

Group 2 elements also react when exposed to air or water, but their reactivity is not as strong as that of the alkali metals

Question 31

Halogens

Answer 31

Group 17 elements, are the most reactive non-metals. Fluorine, chlorine and bromine gas are all reactive elements called halogens that can create new compounds when combined.

Question 32

Noble gases

Answer 32

Group 18 elements, the noble gases are the most stable and unreactive elements