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The graph shows the boiling points of the straight-chain alkenes with a terminal double bond, from ethene to hex-1-ene. (i) Explain why the boiling point rises from ethene to but-1-ene. (ii) A sample of but-1-ene is warmed from 250 K to 300 K at constant…
Ethane reacts with bromine gas, Br2(g), in the presence of UV light to form bromoethane. State the type of this reaction and the name of its mechanism.
1-Bromopropane can be converted into propan-1-ol. Identify a suitable reagent and the conditions needed for this conversion.
Young mussels were placed in a contaminated harbour. Samples were taken at regular intervals and the tin content of the soft tissue was determined. (i) The tin content follows a linear trend during the first six weeks. Deduce the equation for this part of the…
The concentration of tin in a sample of mussel tissue is 0.0064 ± 0.0002 mg Sn g−1. (i) Calculate the mass of tin, in mg, in 2.416 g of the sample. (ii) Calculate the percentage uncertainty of the concentration.
Suggest two variables that should be controlled when mussels are collected and their soft tissue is sampled.
Antimony(III) sulfide burns in air to form antimony(III) oxide and sulfur dioxide. Sb2S3(s) + O2(g) → Sb2O3(s) + SO2(g) The equation is balanced using the smallest whole-number coefficients. What is the sum of all the coefficients? A. 8 B. 15 C. 19 D.…
2-Methylbut-1-ene contains sigma (σ) and pi (π) bonds. (i) State the hybridization of carbon atoms A and B. (ii) Describe how the sigma bond and the pi bond of the carbon-carbon double bond in 2-methylbut-1-ene are formed.
2-Methylbut-1-ene reacts with hydrogen bromide, HBr, to give two structural isomers of C5H11Br. (i) Deduce which of the two isomers is formed in the larger amount and explain your choice. (ii) Using curly arrows to show the movement of electron pairs,…
Suggest why it is important that hydrogen gas flows through the tube (i) before heating begins, (ii) from the end of heating until the product has cooled.