Chemistry Paper 1 for Science yr 10 (merged)

What are all substances made from?

Atoms

What is the smallest part of an element that can exist?

An atom

Approximately how many different elements are there?

100

Where are all of the elements shown?

The Periodic Table

What are formed from elements by chemical reactions?

Compounds

What do chemical reactions always involve?

The formation of new substances

What is this the definition of:
Substances containing two or more elements chemically combines in fixed proportions

Compound

What is this the definition for:
Something consisting of two or more elements or compounds not chemically combined together

Mixture

Which processes can be used to separate mixtures?

Filtration, Crystallisation, Distillation, Chromatography, Fractional Distillation

Before the discovery of electrons what were atoms thought to be?

Tiny spheres that could not be divided

Which model was created due to the discovery of the elctron?

The Plum Pudding Model

What does the Plum Pudding Model suggest about the electron?

That it is a ball of positive charge with negative electrons embedded in it

What did the results from the alpha particle scatting experiment show?

That the mass of an atom was concentrated at the centre (nucleus) and the nucleus was charged

How did Niels Bohr adapt the nuclear model?

He suggested that electrons orbit the nucleus at specific distances

What is the name given to small positively charged particles in the nucleus?

Protons

What did the experimental work of James Chadwick provided the evidence for?

Neutrons

What is the relative charge of the proton?

+1

What is the relative charge of a neutron?

0

What is the relative charge of an electron?

-1

In an atom the number of electrons is equal to the number of

Protons

What is the atomic number of an element?

The number of protons

All atoms of a particular element have the same number of?

Protons

Atoms of different elements have different numbers of

Protons

What is the radius of an atom?

0.1nm (1x10^-10m)

How many times smaller is the radius of the nucleus compared to the atom?

10,000

What is the relative mass of a proton?

1

What is the relative mass of a neutron?

1

What is the relative mass of an electron?

Very small

What is the mass number of an atom?

The sum of the protons and neutrons

What do we call atoms of the same element with different numbers of neutrons

Isotopes

Isotopes of an element have a different number of?

Neutrons

What is the relative atomic mass of an element?

The average values of the abundance of the isotopes of the element

What is the maximum number of electrons that can be found on the lowest energy level?

2

What is the maximum number of electrons that can be found on the second energy level?

8

How are the elements in the periodic table arranged?

In order of atomic number

What do we call a column in the periodic table?

Groups

What do we call rows in the periodic table?

Periods

What do elements in the same group in the periodic table have in common?

The same number of electrons in their outer shell

Before the discovery of protons, neutrons and electrons how did scientists classify the elements?

Arranging them in order of their atomic weights

How did Mendeleev overcome problems with creating a periodic table?

By leaving gaps for undiscovered elements

Elements that react to form positive ions are

Metals

Elements that do not form positive ions are

Non-metals

The majority of elements are

Metals

Where are metals found on the periodic table?

To the left and bottom

Where are non-metals found on the periodic table?

To the right and top

What do we call the elements in Group 0?

The noble gases

Why are Group 0 elements unreactive and do not easily form molecules?

They have stable arrangements of electrons

How many electrons do the noble gases have in their outer shell (excluding Helium)

8

What happens to the boiling point of the noble gases as you go down the group?

It increases

Which noble gas has 2 electrons in the outer shell?

Helium

What are the elements in Group 1 know as?

The alkali metals

How many electrons are there in the outer shell of the alkali metals?

1

How does the reactivity of the elements in Group 1 change as you go down the group?

It increases

What is the general equation for the reaction of an alkali metal with chlorine?

What is the general equation for the reaction of an alkali metal with chlorine?
Alkali metal + Chlorine makes Metal chloride

What is the general equation for the reaction of an alkali metal with water?

Alkali metal + Water makes Metal hydroxide + Hydrogen

What is the general equation for the reaction of an alkali metal with oxygen?

Alkali metal + Oxygen makes Metal oxide

What are the elements in group 7 known as?

The Halogens

How many electrons do the Group 7 elements have in their outer shell?

7

How are the halogens found?

In pairs of atoms

As you go down Group 7 what happens to the boiling points of the elements?

It increases

As you go down Group 7 what happens to the relative molecular mass of the elements?

It increases

As you go down Group 7 what happens to the reactivity of the elements?

It decreases

What will a more reactive halogen do to a less reactive halogen when in an aqueous solution of its salt?

Displace it

What transition element is used in the Harber process?

Iron

What transition element increases the decomposition of hydrogen peroxide to oxygen and water?

Manganese (IV) oxide

What can the transition elements form?

Coloured compounds
Ions with different charges

What colour does Iron(II) hydroxide, Fe(OH)2

Pale green

What colour does Iron(III) hydroxide, Fe(OH)3

Orange
Brown

What colour does Iron(III) oxide, Fe2O3

Red-brown

What can the transition elements be used as?

Catalysts

What are the transition elements?

Metals

What are the main transition elements?

Chromium, Manganese, Cobalt, Nickle, Copper

How should the transition elements be simplified as?

Cr, Mn, Fe, Co, Ni, Cu

What do the transition elements have in common?

They have similar properties

How do the transition elements differ from Group 1 metals?

higher melting points
higher densities
Stronger and harder
Reactivity with oxygen, water and halogen -Conducts electri

What type of bonding occurs between oppositely charged ions?

Ionic bonding

What type of bonding occurs between atoms which share pairs of electrons?

Covalent bonding

Which type of bonding is found in atoms which share delocalised electrons?

Metallic bonding

Which type of bonding occurs in compounds formed from metals combined with non-metals?

Ionic bonding

Which type of bonding occurs in most non-metallic elements?

Covalent bonding

Which type of bonding occurs in compounds of non-metals?

Covalent bonding

Which type of bonding occurs in alloys?

Metallic bonding

What is transferred in ionic bonding?

Electrons

When a metal atom becomes positively charged what has it lost?

Electrons

What would be the charge of an ion formed from a Group 1 element?

+1

What would be the charge of an ion formed from a Group 2 element?

+2

What would be the charge of an ion formed from a Group 6 element?

2-

What would be the charge of an ion formed from a Group 7 element?

-1

What is an ionic compound?

A giant structure of ions

What holds ionic compounds together?

Strong electrostatic forces of attraction between oppositely charged ions

Name 2 covalently bonded substances with giant covalent structure

Diamond, Silicon dioxide

Some covalently bonded substances have very large molecules, such as

Polymers

How are the atoms arranged in metals?

In a regular pattern

What are the electrons in the outer shell of metal atoms like?

Delocalised

What does delocalised electrons mean?

Electrons that are free to move around

What are the three states of matter?

Solid, Liquid and Gas

What takes place at the melting point?

Melting and Freezing

What takes place at the boiling point?

Boiling and Condensing

How does the strength of the forces between particles affect the boiling point?

The stronger the forces between the particles the higher the boiling point

What are the limitations of the particle model?

There are no forces
All particles are represented as spheres
The spheres are solid