Which of these compounds is covalently bonded?
Iron oxide
Magnesium sulphate
Carbon dioxide
Sodium chloride
Which are properties of metals?
High melting and boiling points
Often gas at room temperature
Brittle; easy to break
Hard and shiny
Dense
Sonorous
Often highly reactive
Poor conductors
Good conductors
Malleable and ductile
Nitrate (NO3) has a valency of 1.
When phenolphthalein comes into contact with an acid, it goes bright pink/purple.
Which of the following increases rate of reaction?
Increasing temperature
Adding a catalyst
Decreasing concentration
Increasing surface area
Adding a barbiturate
Reactivity increases as you go down the Group 1 metals.
Which of these salts are insoluble?
Potassium nitrate
Barium sulphate
Silver bromide
Sodium carbonate
Calcium carbonate
Find the chemical equation for: Hydrogen peroxide -> water + oxygen
H2O2 -> 2H2O + O2
H2O2 -> H2O + O
2H2O2 -> 2H2O + O2
H2O2 -> H2O + O2
Why is a polystyrene cup used in the experiment to find a temperature change?
Because it is safer.
Because it is an insulator.
Because it is cheaper.
Because it is light.
Which of these are halogens?
Oxygen
Potassium
Chlorine
Fluorine
Helium
Iodine
Copper
Bromine
Halogens exist as monatomic molecules.
Which of the following compounds are ionically bonded?
Potassium chloride
Sulphur dioxide
Copper nitrate
Magnesium oxide
Hydrogen bromide
The ∆H for an exothermic reaction is a negative value.
Which of these would you observe in the reaction between sodium and water?
Shoots around surface of the water
Hissing sound
Burns with a lilac flame
Effervescence/fizzing
Never disappears
Melts into a shiny ball
The noble gases are unreactive because they are too large and have very weak electrostatic forces.
What is the test for carbon dioxide?
Burns with a squeaky pop
Turns limewater milky
Relights a glowing splint
Bleaches paper
Which gas relights a glowing splint?
Ammonia
Hydrogen
In the reaction between potassium chloride and iodine, iodine displaces chloride to form potassium iodide.
Which are properties of the halogens?
Highly reactive
Alkaline
Poisonous
Bleaches
Metals
Form diatomic molecules
Painkillers
Form coloured gases
Why does increasing temperature increase rate of reaction?
Higher quantity of particles, so there are more frequent collisions.
More kinetic energy, so particles collide more often and more frequently.
Lowers the activation energy required for reactions.