When drawing Lewis structures, straight lines are drawn in-between atoms to indicate bonds. Common bonding arrangements include single bonds, double bonds and triple bonds. From the options below, indicate how many electrons are represented by each

Which of the four resonance structures for ozone below is the least likely? Remember to consider the formal charge on each atom, and the number valence electrons in the structure.

Please note: there is more than one correct answer (but you only need to select one!)

Which of the four resonance structures for the nitrate ion below is the least likely? Remember to consider the formal charge on each atom, and the number valence electrons in the structure.

Select the most rational Lewis structure for SO₂ from the figure provided.

b) Calculate ΔH, in kJ mol^-1, if all the NaHCO₃ dissolves in the water.

Report your value to 4 significant figures, and do not include units in your answer.

Calculations

When 5.000 g of NaHCO₃ is added to 600.0 g of water in a ‘coffee cup calorimeter’, the temperature decreases from 21.52°C to 19.07°C.

a) Calculate q_calorimeter, in joules, assuming the specific heat capacity of the solution is the same as pure water: 4.186 Jg^-1K^-1.

Report your value to 4 significant figures, and do not include units in your answer.

Questions

The Reaction

What is the balanced chemical equation for today's experiment? Select the correct coefficients for each reagent and product.

A: 

B: 

C: 

D: 

E: 

F:

Which product explains the presence of bubbles observed at the start of the experiment video? 

What type of reaction is it? 

Is it an endothermic or an exothermic reaction?

What would the energy diagram for this reaction look like, A or B?

Diagram from LibreTexts Chemistry.

Results

Graphs:

• ΔT vs the mass fraction of citric acid 
  Image failed to load: mass fraction
• ΔT vs the mole fraction of citric acid 
  Image failed to load: molar fraction

Upload a single PDF of your two graphs here.

Marking Rubric per graph (0.5 marks each, 3 marks total/graph):

• Title
• Labelled axis (including units)
• Scale of graph (appropriate and even)
• Minimum of 7 data points recorded per graph
• Negative ΔT values
• Line of best fit

A uni student is listening to Top 40 Music on her FM radio, tuned into a wavelength 3.02 m. Convert this value into a frequency, in MHz.

Use the speed of light, c = 3.00 x 10⁸ ms^-1.

Give your answer to 3 significant figures. Do not enter units!