Chemisty page 21

Seite 1

Name the sub atomic particles found in the nucleus: Protons and neutrons

What is the maximum number of electrons that can occupy the first 2 shells: 10

Explain the overall charge of an atom: Protons and electrons are oppositely charged. Neutrons have no charge. This means the nucleus of an atom is always positively charged. An atom has a neutral overall charge because it has the same number of electrons as protons

How can an atom become an ion with a 2+ overall charge: Atoms lose the electrons, in their highest energy level and become positively charged ions.

Define atomic mass: the mass of an atom of a chemical element expressed in atomic mass units. It is approximately equivalent to the number of protons and neutrons in the atom.

Define mixture: a combination of different things in which the component elements are individually distinct and not chemically bonded.

What's the difference between a mixture and a compound: The different substances are not chemically joined together. Each substance in the mixture keeps its own properties. The compound has properties different from the elements it contains. Each substance is easily separated from the mixture

How to separate hydrated copper sulphate from it's aqueous form: copper sulfate is soluble in water – its crystals dissolve in water to form copper sulfate solution. During evaporation, the water evaporates away leaving solid copper sulfate crystals behind.

How to separate lead iodide from the solution formed: When aqueous solutions of Precipitation can be used to produce insoluble salts by reacting two soluble salts. When the ionic solutions are mixed and all the ions are present, if a positive and negative ion form an insoluble compound, this compound will form as a precipitate. Colourless solutions of lead nitrate and sodium iodide can be mixed to produce a bright yellow precipitate.

Lead Nitrate (aq) + Sodium Iodide (aq) → Sodium Nitrate (aq) + Lead Iodide (I)

Water from a solution of potassium chloride: distillation

Ethanol from a mixture of water and ethanol: fractional distillation

Which state are these elements in at 25degrees?: Bromine-liquid, Caesium- solid, Fluorine- Gas, Strontium- solid, Xenon- gas

Which element lasts longest as a liquid?: Strontium

What is the chemical symbol for each of the elements in this table?:Bromine- Br, Caesium- Cs, Fluorine- F, Strontium-Sr, Xenon- Xe

What is a metal and what is a non metal: Bromine- non-metal, Caesium- metal, Fluorine- metal, Strontium-metal, Xenon- metal

Electronic Structure of Fluorine: (2,7)

Electronic Structure of Fluorine-: (2,8)

Seite 2

Is neon a metal or a non metal?: non metal

Are there more metals and non metals in the periodic table?:metal

How many protons does a neon atom contain?: 10

The mass number of a neon atom is 20. How many neutrons does it contain?: 10

What group number/name does neon belong to?: group 0

Name 2 elements in the same group of Neon?:Helium and Argon

Write the electronic structure of a neon atom?: (2,8)

What is special about the electronic structure of neon and the other elements in it's group?: It has a complete shell that cannot react with anything

How many protons are in a radium atom?: 88

How many electrons does a radium atom have in its highest energy level?: 2

Is radium a metal or a non metal?: Metal

Calcium is in the same group as radium. It's atomic number is 20. What is its electronic structure?: (2,8,8,2)

2Na+Cl2---> 2NaCl

2Al+1O2---->Al2O3

Seite 3