To find out if Chlorides of metallic elements have a higher melting point than Bromides of metallic elements.

Hypothesis:- I think the statement that Metal Chlorides have a higher melting point than Metal Bromides is true because chlorides of metallic elements have greater ionic strength then metallic bromides.The reasons for this can be that bromine is below chlorine in the same group and as you go down a group the atomic radii increases and the force of attraction of the protons on the electrons decreases so the elements down a group from weak bonds with elements in this case metals so have a lower melting point as compared to the compounds formed by elements above it in the same group and metals. Plan:- I will kick off my investigation with the collection of data. I will collect my data using a Random sampling method.I will collect about 50 samples for metal chlorides and metal bromides so that my data is reasonable and will be more spread out than 20 or 30 data samples which would not only make this investigation more effective but also more reliable. To help me conclude my investigation I will make diagrams such as Cumulative frequency graphs and Box and Whisker Diagrams. I will analyze my data and calculate the mean of the melting points of metal chlorides and metal bromides which will give me an average of the melting points of metal chlorides and metal bromides which will help me compare my data easily and conclude my investigation.

Data Collection Process: – I will collect my data using a Random sampling method because this way the calculator will choose the atomic numbers for me and this will be a fair investigation. I pressed the buttons to get the numbers for my data. All numbers that were grater than 118 were ignored so were the non-metallic elements and metalloids. I decided to have 50 samples for both metal chlorides and metal bromides so that the investigation, the data and the conclusion is not only right but also reliable.For Example: – the first number I got off my calculator was 0.026 which meant element number 26 which is iron so I added iron to my list of data and found out the melting point of iron chloride and iron bromide using the website www. webelements. com .

I used this website because it is easy to use and the information is reliable because the website is owned by The University Of Sheffield and is used by professional scientists and students at school interested in chemistry and incorrect information would earn the University a bad name. I did the same thing for the rest of my data.I used this method so my data was fair and reasonable and the investigation was not unfair. The Statistics that I have calculated are Mean, Median, Upper Quartile and Lower Quartile. The statistics helped me make a Box and Whisker Diagram because this is the easiest and the most effective method that I know of to compare my statistics. The Mean that is the average temperature helps to compare the average temperature of the metal chlorides and metal bromides; in this case it shows that the metal chlorides have a higher average melting point than metal chlorides.

The upper and lower quartile helped to compare the temperatures at 75% and 25% respectively. With the median the temperature was compared at 50%. According to my statistics the metal chlorides have a bigger upper and lower quartile than metal bromides but metal bromides have a higher median than metal chlorides. The statistics show that metal chlorides do have a higher melting point than metal bromides.

This proves that my hypothesis was true and the fact that I took 50 data samples for each metal chloride and bromide not only proves my hypothesis is true but also that the results are reliable.I have compared the upper quartile, lower quartile and median obtained through the graphs with the ones obtained through calculations, and these are fairly close to each other which shows that my investigation was successful. Conclusion: – I found out that my data was true because all of statistical evidence supports the fact that metal chlorides have a higher melting point than metal bromides.

I could improve the method of doing this investigation by taking more samples than I previously did, this way I will have more metal chlorides to compare with metal bromides making my investigation more precise and accurate.