pt 2

Created by

jay sharma

Cards (15)

what is a catalyst 
a substance which speeds up the rate of reaction without being used up itself
how does a catalyst increase the rate of reaction
it provides an alternate reaction pathway with a lower activation energy
what are enzymes 
enzymes are biological catalysts that increase the rate of reactions in living cells
which enzyme is used to produce ethanol from glucose
yeast
what do the terms endothermic and exothermic mean
endothermic- a reaction that takes in heat energy from the surroundings
exothermic - a reaction that gives out energy to the surroundings
are neutralisation reactions exothermic or endothermic
exothermic
are displacement reactions exothermic or endothermic  
either
is a salt dissolving in water endothermic or exothermic  
either exothermic or endothermic
are precipitation reactions endothermic or exothermic
exothermic
how could you measure the temperature change of a neutralisation reaction
measure the initial temperature of the solutions , mix both of the reactants in a polystyrene cup
record the highest temperature reached
calculate the temperature change
when measuring the temperature change of a reaction , heat loss means that easurements may be innacurate . how could heat loss be minimised during an experiment
use polystyrene cup
place reaction cup in a beaker full of cotton wool for better insulation
lid on the cup to stop any heat escaping
what type of reaction is bond breaking
endothermic
why is bond breaking an endothermic process
energy must be supplied to break existing bonds
what type of reaction is bond formation
exothermic
why is bond forming exothermic
energy is released when bonds are formed