Molecular Chemistry

Complete the table with the positive ion, negative ion, and the formula for the compounds. Use the subscript (X₂) and superscript (X²) buttons as needed.

68. How many molecules of sulfur dioxide are present in 1.60 moles of sulfur dioxide? Show all your work.

1) Compute the molecular weight of the following compounds using the periodic table. C6H12O6 NaOH H₂S FeCl3 C6H5CH3

1) Nanochemistry focuses on designing and producing innovative materials and technologies.However there are concerns regarding safety and eco-impact a) Identify 2 areas where nano materials could have a strong impact in the future and describe how nano materials can be used in 2 types of applications within each of these areas. b) Explain 1 possible chemical approach that could be useful for reducing the cytotoxicity effects of toxic nanoparticles (i.e. CdSe QDs)? c) What would you think is most important in what concerns safety of nano materiaks forbio-nano applications: size, shape or surface? Explain your reasoning for your choice.

Examine the following image of sodium chloride. Use that image to describe the compound. Then look up and record its density and melting point from the reference materials.

2 - Formulas of lonic Compounds (5pts) Complete the table with the positive ion, negative ion, and the formula for the compounds. Use the subscript (X₂) and superscript (X2) buttons as needed.

Hair-dyes are cosmetic products that are used to either permanently or temporarily colour the hair.Ammonia is often used in hair dyes as it helps during the dyeing process. A cosmetic company is undergoing quality control checks to assess the percentage of ammonia in their2 new hair dyes. Dye A was expected to have (4.5+0.1)% ammonia and dye B was expected to have (7.5t0.1)%ammonia. 25.0g of dye A was transferred to a volumetric flask and made up to 250.0ml. with distilled water.The same was repeated for dye B. A 25.0mL portion of dye A was then transferred to separate conical flasks and titrated against a 0.125 M solution of sulphuric acid. The same was repeated for dye B. The results of experiment are show below: a) Use the information above to determine the percentage of ammonia in both dye A and B and state whether or not they meet the requirements. b) A student conducted an experiment to determine the volume of 1.50OM hydrochloric acid that was required to react completely with 1.75g of magnesium carbonate. The student deduced that exactly 13.88ml. were required. Show, by calculation, why this was incorrect and suggest the error this student made in the calculation.(4 marks)