Module 3 Chapter 7 and 8 Flashcards
What is the reaction between Group 2 metal and water
Metal hydroxide and hydrogen is produced
What is the type of reaction when calcium carbonate forms calcium oxide
Thermal decomposition `
A student prepared some calcium hydroxide by adding a small piece of calcium to a large excess of water.
Describe what the student would observe and write the equation for the reaction
The student would observe the calcium to dissolve into the water and bubbling would be produced.
Ca + 2H2O => Ca(OH)2 + H2
What are the trends in group 1 and 2 as you go down the group
Melting point decreases
Metallic strength increases
Reactivity increases
What is the trend in hydroxide of group 2 as you go down the group
The PH increases
Solubility increases
Alkalinity increases
What happens to halogens as you go down the group
Melting point increases
Reactivity decreases as more energy is required to break the london forces
Explain why the first ionisation energy of strontium is less than the first ionisation energy of calcium .
Strontium has a larger atomic radius and less nuclear attraction and therefore more shielding.
Describe two observations which would be different if the student had used calcium instead of strontium
The time for calcium to dissolve in water would be slower
Less vigorous Bubbling
Define the term electronegativity
Power of an atom to attract electrons in a covalent bond
State why argon (noble gas) has no electronegativity value.
Forms no compounds
Why are silicon, carbon, oxygen and chlorine all classified as p block elements
highest energy electron in a p orbital
What is the equation for bleach
2NaOH + Cl2 –> NaClO + NaCl + H2O
What are the uses of group2
Ca(OH)2 is used to reduce soil acidity
Mg(OH)2 is used to treat indigestion - neutralises HCl in stomach
Define ionisation energy
Amount of energy required to remove the one electron in one mole of each atom in the gaseous state
What is the order of qualitative analysis
- Carbonate test
- Sulfate Test
- Halide test
- Test for ammonium
