Atoms Elements and COmpounds.

Atoms

The smallest part of an element containing its properties.

Element

A pure substance made up of only one type of atom.

What are the subatomic Particles?

protons, electrons, neutrons

What is the charge of a proton?

+1

What is the charge of an electron?

-1

What is the charge of a neutron?

0

Where are protons and neutrons in an atom located?

In the nucleus of the atom.

Where are electrons located in an atom?

They orbit in the electron shells surrounding the nucleus.

what is the mass of one proton (amu)?

1 (simplified)

what is the mass of one neutron (amu)?

1 (approximately)

what is the equation to find an element’s atom’s relative atomic mass

Protons + Neutrons (electrons’ mass is negligible and ignored)

what is the mass of one electron

1/1840 or 0.00054

What are the distinguishing features of Group 1 elements?

They are Alkali, metals, and have one electron in the outermost shell.

What are the distinguishing features of Group 2 elements?

Alkaline earth metals, 2 electrons in outrmost shell.

What are the distinguishing features of Group 3 elements?

They have 3 electrons in their outermost shell.

What are the distinguishing features of Group 4 elements?

They are the “Carbon Family” and have 4 electrons in their outermost shell.

What are the distinguishing features of Group 5 elements?

They are the “Nitrogen Family” and have 5 electrons in their outermost shell.

What are the distinguishing features of Group 6 elements?

They have 6 electrons in their outermost shell.

What are the distinguishing features of Group 7 elements?

HALOGENS, with 7 electrons. They are highly reactive, coloured gases and are poisonous. They react to Group 1 elements.

What are the distinguishing features of Group 8 elements?

The Noble Gases which are Inert or non reactive (don’t form compounds)

What are the rules for writing electronic configuration?

2 electrons capacity in first shell, up to 8 in every other shell.

What is an ion?

An ion is an electrically charged particle formed when an atom gains or loses electrons.

Where do atoms gain/lose electrons?

In their valence shell (outermost).

What is a cation?

A positive ion formed when atoms lose electrons, which results in a higher amount of protons as compared to electrons.

What is an anion?

A negative ion formed when atoms lose electrons, which results in a higher amount of electrons as compared to protons.

How are ions formed in different element groups?

Groups 1, 2 and 3 lose electrons to form cations. Their charge is positive and the same as their group numbers. Transition elements and group 4 are not covered. Groups 5, 6 and 7 gain electrons to form anions. Group 8 elements don’t form any ions.

Why don’t group 8 elements form ions?

They are already stable.

What is an isotope?

Isotopes are atoms of the same element with different numbers of neutrons but the same number of protons.

Can isotopes be made?

They are only found naturally.

What is the difference between atoms of different isotopes within the same element?

They have the same chemical properties as proton and electron numbers remain the same. The mass of the atom changes and resultantly the physical properties dependent on it (such as boiling point, density) are altered.

What is Relative Atomic Mass?

Relative Atomic Mass (AMU) is the average mass of an isotope of an element compared to 1/12th of the mass of an atom of carbon C-12 (an isotope of Carbon containing 12 neutrons). e.g Hydrogen has an amu of 1

How does one calculate the relative atomic mass of an element?

It is calculated from the actual mass number and relative abundances (percentage of said atom occuring naturally) of all isotopes. aka [(% of isotope*mass of isotope) +….]/100

How are compounds formed?

Compounds are formed when chemical reactions cause the reactants to form one or more new substances called the products. Compounds formed through chemical reactions have different properties than their original elements.

What is the prefix of a compound formed out of two substances?

It is -ide

What is the suffix of a compound where three or more different elements combine and one of them is oxygen?

-ate or -ite

What is a binary compound?

A binary compound is a compound made of out just two elements.

What is a molecule?

A molecule is two or more atoms joined together. Their join is known as a chemical bond.

What are diatomic molecules?

Molecules of elements which always form by combining two of themself. (unrelated: some elements also form in

What are monoatomic elements?

Monoatomic elements are those which are composed of seperate, individual atoms. They are gaeous elements.

What is an element?

An element is a pure substance that contains only one kind of atom. All elements have varying properties.

What are the two main categories of elements?

Metals and non-metals.

What is a compound?

A pure substance made up of two or more elements chemically combined.

What is a pure substance?

A pure substance is one made completely out of just one element or compound.

What is a mixture?

An impure substance formed by mixing two or more substances (elements and/or compounds) that are not chemically combined

What are the properties of a compound?

They are pure substances. They are synthesised through the means of chemical change. They have a chemical formula. The elements are in fixed proportions. The elements may only be seperated through chemical change.

What is a mixture?

They are impure substances

They are formed by a physical change

They do not have a chemical formula

Substances are not present in a fixed proportion

The components can be separated easily by

physical change

What is the number of electrons in a neutral atom?

In a neutral atom, electrons are equal to protons in the atomic number.