What affects the rate of reaction between Sodium thiosulphate and Hydrochloric acid

What affects the rate of reaction between

Sodium thiosulphate and Hydrochloric acid?

Introduction

A chemical reaction can only happen if the molecules frequently and successfully collide into each other. These molecules have to hit each other in the right direction and at the right speed and with the right amount of energy.

Prediction

I predict that the more concentrated the acid the faster the rate of reaction.

Theory to back up my prediction

Particle theory tells us that the more particles the more frequent successful collisions there will be. When the concentration of the acid is increased the rate of reaction increases because of more successful collisions.

Low concentrated acid High concentrated acid

Variables:

The rate of reaction depends on four things

Catalyst- A catalyst speeds up the rate of reaction without using itself, giving the particles a surface to stick to so they are able to have more frequent collisions.
Concentration -Concentration of a reactant affects reaction rate because there are more frequent successful collisions.
Temperature- When the temperature is increased the particles move quicker this causes them to have more frequent successful collisions.

Size of Particle (surface area) – If a solid reactant is broken up increasing surface area so the more area for successful collisions.

Plan

In this experiment I am going to investigate what affects the rate of reaction between sodium thiosulphate and hydrochloric acid. I will measure the rate of reaction by the time taken for the liquid to turn cloudy. This is called precipitation when the product of the precipitate makes the solution cloudy. So by observing the cross through the solution, to see how long ...