Lesson 7 - Alkali Metals PDF

Alkali metals Do now: 1. What is the chemical symbol of silver, sodium, iodine and argon? 2. What group is oxygen in? 3. What period is magnesium in? 4. Why is gold suitable for making jewellery? 5. What chemical is used to test for starch?  Group 1 Corre...

Alkali metals Do now: 1. What is the chemical symbol of silver, sodium, iodine and argon? 2. What group is oxygen in? 3. What period is magnesium in? 4. Why is gold suitable for making jewellery? 5. What chemical is used to test for starch?  Group 1 Correct the mistakes on the chemical symbols below. 7 223 86 Li Na Rf 5 87 37 40 23 133 K Fr Cs 19 11 55  Properties of alkali metals - observation 1. Describe why alkali metals are task. Observation Observation Observation of Alkali kept in oil? metal before cutting after cutting alkali metal in water 2. Explain why K returns back to Li grey faster than Li? Na 3. Why are alkali metals called alkali metals? K When lithium reacts with oxygen it forms lithium oxide. When lithium reacts with water it forms lithium hydroxide and hydrogen gas. When lithium reacts with the group 7 element (chlorine) it forms lithium chloride.  Group 1 Also known as the alkali metals THEY FORM ALKALINE SOLUTIONS WHEN DISSOLVED IN WATER Shiny when freshly cut Good conductors of heat and electricity Lower melting points than other metals  Answer in full sentences in your Group 1 trends book. Describe the trend in melting point of Group 1 elements. Compare the melting point of Group 1 metals with other metals.  Group 1 trends As you go down the down, the boiling point also decreases.  Reactivity down group 1 What do all alkali metals want to do to get a full outer shell? lithium Is it easier to lose one electron or to gain 7 in this 2,1 group? Attraction Shielding – sodium Distance between between the number of shells 2,8,1 the nucleus (+) nucleus and between the and the outer outer electron nucleus and electron shell (-) shell. outer shell. Challenge: Explain why reactivity increases down potassium group 1 using the points above. Discuss what 2,8,8,1 happens to the shielding, nuclear attraction and the distance between the nucleus and the outer shell. (6)  Ideal answer Mark this with a green pen. Attraction Shielding – Distance between between the number of shells the nucleus (+) lithium nucleus and between the and the outer 2,1 outer nucleus and electron shell (-) electron. outer shell. sodium 2,8,1 Group 1 elements want to lose an electron to get a full outer shell. As you go down the group, the atom gets bigger. There is more shielding (more shells between the nucleus and the outer shell) potassium The distance between the nucleus and outer shell 2,8,8,1 increases. The attraction between the nucleus and outer electron decreases. It is easier to lose the electron down the group. EQ: EQ: MS- GREEN PENS