Trends in chemical properties of group 2. Reactivity Group 2 are less reactive than group 1. Na vigorously reacts with water. But Ca reacts very slowly.

Slides:

Advertisements

Similar presentations

Reactions of metals with acid

Advertisements

When a lump of zinc is added into copper sulfate solution, the two slowly react to produce very small dark copper granules and zinc sulfate solution.

Everyday acid and base reactions. Calcium carbonate and rocks. Limestone is also largely composed of calcium carbonate. Bath Stone (Greater Oolite) is.

Acids, Bases and Salts Mrs Teocc.

Topic 9 Reactions of Acids.

Produced by Dan Dean Bramcote Hills Science Department Chemical Ideas 11.2 The s block: Groups 1 & 2.

Chemistry My family and home 03/07/2015. Acids and bases (alkalis) Used by the body, used in other processes: such as food, farming and chemical industries.

Calderglen High School

Acids, Alkalis and Indicators Prepared by Mdm RY Leow The Chinese High School.

METAL OXIDES & HYDROXIDES.  These are mostly insoluble (can’t be dissolved in water) EXCEPT! -Those containing Sodium (Na+) -Those containing Potassium.

Making Salts Soluble salt Insoluble salt Acid + excess insoluble solid

MAKING SALTS 27/08/2015. Making Soluble Salts There are 3 types of reaction that can be used to make soluble salts. All 3 involve: An Acid A metal or.

The Periodic Table Lesson Objectives:

Acids and Alkalis Learning Objectives To know that solutions can be sorted by whether they are: acid, alkali or neutral. To understand that an alkali reacts.

12.6 – How can we use ions in solutions?

Group 2 Reaction of Group 2 Oxides and Hydroxides.

Acids & Bases  What is an acid? (It is defined by its behavior in water.)  What is a base?  What does neutralization mean?  What are the products of.

11/10/2015 Reactions of metals and metal compounds.

Click to add text : CHEMICAL REACTIONS. Chemical reactions: Reactions that produce new substances PRODUCT: substance formed during a chemical reaction.

Salts By Amy Badger.

Single & Double Replacement, Synthesis and Decomposition

GROUP II Alkaline earths CONTENTS ©HOPTON General properties

Acid reactions. Metals and acid reaction Example Magnesium Metal (Mg) reacts with Hydrochloric acid (HCl) to produce Hydrogen Gas and Magnesium Chloride.

Chemistry 1011 Slot 51 Chemistry 1011 TOPIC Solubility Equilibrium TEXT REFERENCE Masterton and Hurley Chapter 16.1.

Calderglen High School

CCBAB Compound ABCompound CD AD Compound ADCompound CB D ++ Magnesium Chloride MgCl 2 Calcium Hydroxide Ca(OH) 2 Magnesium Hydroxide Mg(OH) 2 Calcium Chloride.

Revision Quiz Acids 1 1.What is the pH scale? 2.What numbers on the pH scale show an acid? 3.What is an indicator? 4.What number is neutral? 5.What colour.

GROUP II CONTENTS ©HOPTON General properties

Chemical Reactions: Chapter 9 Reactants change chemical and physical properties …. to become new substances made from the same elements; these are called.

Acids and Alkalis Year 11. CONTENTS Acidity and alkalinity Indicators pH Acids General methods for making salts Making salts from metal oxides Making.

AN INTRODUCTION TO GROUP II Alkaline earths KNOCKHARDY PUBLISHING 2015 SPECIFICATIONS 1s 2 2s 2 2p 6 3s 2 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2.

Colour changes for simple indicators IndicatorColour in acidColour in alkali litmusredblue methyl orangeredyellow phenolphthaleincolourlessred.

SALTS When you hear the word salt, what do you think of?

Group 2 Elements & Compounds

3.2.2 Group 2, the Alkaline Earth Metals

The Periodic Table is arranged according to the Periodic Law. The Periodic Law states that when elements are arranged in order of increasing atomic.

Types of Chemical Reactions SynthesisSynthesis (Combination) reaction DecompositionDecomposition reaction Single-replacementSingle-replacement reaction.

GROUP 2 (ALKALI EARTH METALS) REACTIONS. How would you represent the first, second and third ionisation energies of a general metal? What does the first.

الأستاذة\سارة البلوي. Part (1): Inorganic Qualitative Analysis When an acid, e.g. HCl is made to react with a base, e.g. NaOH, salt, NaCl, and water are.

Properties of Group 2 The alkaline earth metals. Electronic configurations All the alkaline earth metals have two electrons in their outer shell; Be =

Balanced Chemical Equations: Represent reactants, products, and their amounts Make use of chemical formulas i.e. H 2 O can not be altered as they represent.

13.1 REACTIONS OF PERIOD 3 ELEMENTS

Atoms of different elements combine to form compounds by the formation of new chemical bonds Describe how the transfer of electrons produces cations and.

Chemical Changes and Structure

Q: How do atoms of different elements combine to form compounds?

Elements in group 1 & 2 Inorganic chemistry.

Reactions of metals and metal compounds

Dilution and Reactions of Acids

Handle acid with care!.

Acids and Alkalis Grade 10.

Reactions of Acids.

5.2-Salts, Metal Oxides, Non-Metal Oxides

Learning objective: WALT:

KNOCKHARDY PUBLISHING

Chemsheets AS006 (Electron arrangement)

Reactions of metals and metal compounds

8.3 Preparation of salts Demonstrate knowledge and understanding of preparation, separation and purification of salts as examples of some of the techniques.

Reactions of metals and metal compounds

Group 2 The Alkaline Earth Metals.

Reactions of Acids.

Chemsheets AS006 (Electron arrangement)

Learning Objectives Acids and Alkalis

MAKING SALTS 21/06/2019.

SOFTENING METHOD OF WATER

Presentation transcript:

Trends in chemical properties of group 2

Reactivity Group 2 are less reactive than group 1. Na vigorously reacts with water. But Ca reacts very slowly. The difference is due to the amount of energy required to form the metal ion.

Energy needed Li519 kj/mol Na494 K418 Rb402 Cs376 Energy needed Be2660 kj/mol Mg2189 Ca1735 Sr1614 Ba1468

The combined ionisation energies decrease down the group. This means that reactivity increases as it becomes progressively easier to form the M 2+ ion. Energy needed Be2660 kj/mol Mg2189 Ca1735 Sr1614 Ba1468

Reactions of magnesium with water. Magnesium reacts slowly with cold water; Mg + 2H 2 O → Mg(OH) 2 + H 2 Magnesium reacts more readily with steam to form its oxide; Mg + H 2 O (g) → MgO + H 2

Reactions of magnesium hydroxide Mg(OH) 2 neutralises acids. Mg(OH) 2 + 2HCl→ MgCl 2 + 2H 2 O

Treating indigestion. HCl is secreted in the stomach to aid digestion. Excess acid causes indigestion. “Milk of Magnesia” contains magnesium hydroxide so neutralises excess acid.

Reactions of Ca, Sr and Ba with water Calcium reacts rapidly with cold water to give hydrogen and a white percipitate of calcium hydroxide. Ca + 2H 2 O → Ca(OH) 2 + H 2 Strontium and barium react in the same way, but more vigorously.

Reactions of calcium hydroxide Ca(OH) 2 neutralises acids. Ca(OH) 2 + 2HCl→ CaCl 2 + 2H 2 O It is commonly known as “slaked lime” and is used by farmers to lower soil acidity. It is also used in some anti acids.

Relative solubilities of the hydroxides The solubilities of group 2 hydroxides increase from Mg to Ba. Magnesium hydroxide is almost insoluble whereas barium hydroxide readily dissolves. Compound Solubility mol/100g at 298K Mg(OH) 2 2 x Ca(OH) x Sr(OH) x Ba(OH) x 10 -2

Relative solubilities of the sulphates Compound Solubility mol/100g at 298K MgSO x CaSO x SrSO x BaSO x The solubilities of group 2 sulphates decrease from Mg to Ba.

Testing for the presence of sulphate ions. Barium chloride is used as a reagent to test for the presence of sulphate ions. First dilute hydrochloric acid is added to remove any carbonate ions present. CO H + → CO 2 + H 2 O Otherwise white barium carbonate might be precipitated. BaCl 2 + SO 4 2- → BaSO 4 (s) + 2Cl - Barium sulphate forms a white ppt.

Barium meals Soft tissue normally lets through X rays. But barium is opaque, its heavy atom absorbs X rays. A “barium meal”, barium sulphate, can be administered to examine the gut. Although barium salts are highly toxic the sulphate is safe to use as it is insoluble.