Halogen Flashcards
Uses of chlorine
Making bleach
Production of some plastics as PVC
Production of bromine
Production of hydrochloric acid
In purification of drinkable water (sterilising agent
Uses of fluorine
Used in water supply
And toothpaste to prevent the decay of the enamel of the tooth
Uses of iOdine
Used as Antiseptic
Why reactivity decreases from up to down along the group?
As the atoms get larger,the outermost shell gets further from the nucleus,attraction between the nucleus and electrons in the outer shell gets weaker so electrons is less easy to gain electrons
General properties of halogen?
They are diatomic
Bromine is very Voltaile so easy to turn to gas
Halogen are strong oxidising agent as its has high tendency to gain electrons
Outermost energy level of halogens contains 7 electrons
Iodine is dark grey solid when wormed turns into a purple vapour
Halogen are very active elements
What is the most active elements in group 7
Fluorine
Color of fluorine when gas,aqueous,ions
Yellow, colourless, colourless
Colour of chlorine when gas, aqueous,ions
Green,yellow, colourless
Colour of bromine when gas, liquid, aqueous,ions
Orange,brown,orange or red, colourless
Colour of iodine when gas,solid, aqueous,ion
Purple
Dark grey
Brown
Colourless
Colour of astatine when solid and ion
Black, colorless
Write equation of hydrogen chloride when dissolved in water with symbol
Hcl(g)+H2O(l)=hcl(aq)
Write chemical equation when chlorine passed through Aqueous solution of potassium bromide with symbol and what change of colour
Cl2(g)+2kbr(aq)=2kcl(aw)+br2(aq)
Colorless to orange
Give me example when halogen react with hydrogen gas where hydrogen halide formed
H2(g)+f2(g)=2hf(g)
Why hydrogen chloride is gas at room temperature
Because the molecules bondeed by weak inter molecular force
Is reactivity decreases or increase down group
Decrease
Is mp and bp decrease or increase down group
Increase
Write solution of chlorine in water with symbol
Cl2(g)+H20(l)=HCl(aq)+hocl(aq)
HCl(g) is —-compound
Covalent
Hcl (aq) is simple —-structure
Ionic
What will happen when we dissolve HCl(g) in water and why
Give acidic solution by HCl(aq) and turns purple litmus paper to red, conduct electricity and react with active metal due to its ionisation into h+ and cl-
Test for Chlorine gas
Gas turn damp blue litmus paper into red then bleaches
What will happen when HCl(g) dissolve in methylbenzene why
Dissolve as a simple molecule and not ionized,give neutral solution which doesn’t conduct electricity,dont Change colour of litmus paper as it has no free moving ion
