Chemistry atomic structure and the periodic table 2

What are the properties of transition metals compared to group 1 metals?

Transition metals are harder and stronger, have higher melting points (except mercury), higher densities, and are much less reactive, not reacting as vigorously with oxygen or water.

List some transition metals.

Chromium, manganese, iron, cobalt, nickel, copper.

What are typical properties of transition metals?

They have ions with many different charges, form coloured compounds, and are useful as catalysts.

What are the common ion charges for transition metals like iron and copper?

Iron: +2, +3; Copper: +1, +2.

What is one use of transition metals as catalysts?

They are used in the Haber process (N2 + 3H2 ↔ 2NH3) and in the manufacture of margarine by adding H2 to double bonds.

What is the arrangement of elements in the periodic table?

Elements are arranged in order of atomic (proton) number, with elements of similar properties grouped in columns known as groups.

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

They have the same number of electrons in their outer shell, which gives them similar chemical properties.

Who ordered the periodic table by atomic weight and proposed the 'law of octaves'?

John Newlands.

What was Dmitri Mendeleev's contribution to the periodic table?

He ordered elements by atomic mass, left gaps for undiscovered elements, and noted that properties occurred at regular intervals.

What is the significance of the modern periodic table?

It is based on atomic (proton) number, allowing for a more accurate arrangement of elements, including isotopes.

Where are metals typically found in the periodic table?

To the left and towards the bottom of the periodic table.

What are the characteristics of alkali metals in group 1?

They have a single electron in their outer shell, react vigorously with water to create alkaline solutions and hydrogen, and react with oxygen and chlorine.

What happens to the reactivity of alkali metals as you move down the group?

Reactivity increases down the group.

What is a characteristic property of noble gases in group 0?

They have 8 electrons in their outer shell (except helium, which has 2), making them unreactive.

How do the boiling points of noble gases change down the group?

The boiling points increase with increasing relative atomic mass.

What are the properties of halogens in group 7?

They have seven electrons in their outer shell, exist as diatomic molecules (e.g., Cl2), and react with metals to form ionic compounds.

What happens to the reactivity of halogens as you move down the group?

Reactivity decreases down the group due to increased electron shells, which reduce their ability to attract electrons.

What is the result of a more reactive halogen displacing a less reactive one in a solution?

A more reactive halogen can displace a less reactive halogen from its salt solution.

What is the chemical reaction when chlorine displaces bromine from potassium bromide?

Chlorine + Potassium Bromide → Potassium Chloride + Bromine.

What are the typical properties of metals?

Metals are usually hard, malleable, ductile, and good conductors of heat and electricity.

What are the typical properties of non-metals?

Non-metals do not form positive ions and are found on the right and top of the periodic table.

What is the significance of the 'periodic' in the periodic table?

It refers to the occurrence of similar properties at regular intervals.

What is the main characteristic of transition metals that distinguishes them from alkali metals?

Transition metals have multiple oxidation states and form colored compounds.

What is the typical state of halogens at room temperature?

Halogens exist as diatomic molecules made of pairs of atoms.

What is the general trend in melting and boiling points of halogens down the group?

Melting and boiling points increase down the group.

What is a common property of transition metals regarding their physical state?

Most transition metals are solid at room temperature, with the exception of mercury.