Gcse Formulae Of Compounds Flashcards
(28 cards)
Hydrochloric acid
(HCl)
Sulfuric acid
H2SO4
Nitric acid
HNO3
Carbon monoxide
CO
Which elements contain diatomic molecules
Hydrogen, fluorine, chlorine, bromine, iodine, oxygen, nitrogen
What is a catalyst?
A substance that increases the rate of reaction but remains chemically unchanged at the end of reaction
How does a catalyst work?
Provides an alternative reaction pathway with a lower activation energy
What is the rate of reaction?
The rate of a reaction is a measure of the number of successful collisions per unit time
Why does rate of reaction decrease during a reaction?
Reactants are used up in the reaction. As there an are fewer reactant particles, there are fewer collisions between reactant particles per unit time and therefore fewer successful collisions per unit time.
What is collision theory?
Collisions theory states that in order for a chemical reaction to occurs particles must collide with sufficient energy- greater than or equal to the activation energy for a reaction.
What is activation energy?
The minimum amount of energy particles must possess if they are to react when they collide
What does surface area affect the rate of reaction?
More particles of the solid reactant are in contact with particles of the other reactant. This results in more collisions per unit time, so the rate of reaction increases
How does changing the concentration affect the rate of reaction?
Mean ther eare more particles of that reactant in a given volume. There are more collisions between reactant particles per unit time so the rate of reaction increases.
How does temperature affect the rate of reaction?
Particles have more kinetic energy so move around faster. This results in more collisions per unit time, also more particles will collide with energy greater than or equal to the activation energy so more of the collisions will be successful
Example of experiment to investigate effects of change on surface area On a solid.
Small marble chips, big marble chips, gas cylinder . Hydrochloric acid, récord the volume of gas’s produced every 10 seconds .
Example of experiment to investigate effects of concentration of solution
Add marble chips and Hydrochloric acid into conical flask, récord time for 50cm3 of gas to be produced.
Example of experiment to investigate effects of temperature
Put plastic tub in ice water, combine sodium thiosulfate and dilute Hydrochloric acid time how long taken for cross to disappear reappear at room temperature
Example of experiment to investigate effects of catalysts
Put hydro peroxide solution into 4 boiling tubes, add copper oxide(11) , magnese(1V) oxide, copper turnings and potassium iodide to each, when reaction is over filter and when dry weight each of the solids, to see if is chemically unchanged at the end. Look at amount of fizzing.
Covalente bond meaning?
The electrostatic reaction between a shared pair of electrons and the nuclei of the bonded atoms
Complete combustion of hydrocarbons
Hydrocarbon + oxygen -> carbon dioxide and water
What happens when ther is insufficient oxygen for the alkaene to react with?
Incomplete combustion
What is incomplete combustion of hydrocarbons?
Carbon monoxide and water formed
How is carbon monoxide harmful?
It bonds with haemoglobin in the blood to form oxyhemoglobin which prevents it from forming oxyhemoglobin and carrying oxygen around the body.
Car engines?
In car engines the temperature reached is high enough so that nitrogen and oxygen can react from the air to form oxides of nitrogen
