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Sulfapyridine is an antibacterial drug. Its structure is shown below. C11H11N3O2S Mr = 249.32 (i) Deduce the hybridization of the nitrogen atom that is part of a ring. (ii) Describe how the sigma (σ) and pi (π) components of an…
Which equation represents the condensation of bromine? A. Br2(g) → Br2(l) B. Br2(l) → Br2(g) C. Br2(l) → Br2(s) D. Br2(s) → Br2(g)
(i) Write a balanced equation for the reaction, including state symbols. (ii) Deduce what property of this reaction makes it possible to follow its rate by both methods. (iii) Magnesium carbonate was used in excess so that all of the acid would react.…
In Method 1 the flask containing 25.0 cm3 of the aqueous acid was put on the balance, which was then set to zero; 0.400 g of MgCO3 was added and the reading was noted every 20 seconds until the reaction had stopped. Each point is the mean of…
The student repeated the experiment using Method 2, with the same quantities of acid and solid. (i) Calculate the volume of gas that will have collected in the measuring cylinder once the reaction has finished, measured at T = 22 °C and…
(i) Magnesium burns in oxygen according to the equation . Explain, using electron configurations, how ions are formed by magnesium and oxygen and how these ions form a compound. (ii) Explain, using electron configurations, why…
Potassium also forms compounds with polyatomic ions. 2 KOH(aq) + Cu(NO3)2(aq) → Cu(OH)2(s) + 2 KNO3(aq) (i) 30.0 cm3 of a 0.380 mol dm−3 potassium hydroxide, KOH, solution is mixed with 25.0 cm3 of a 0.310…
Some ionic compounds are the product of acid–base neutralization reactions. (i) State the names of the acid and the base that would produce sodium methanoate, HCOONa. (ii) Estimate the pH value of an aqueous solution of sodium methanoate. (iii) Ionic salts can…
What will be the volume of 4.00 dm3 of gas that has had the pressure decreased from 150 kPa to 50.0 kPa, and its temperature increased from 27.0 °C to 127 °C? A. 16.0 dm3 B. 12.0 dm3 C. 56.4 dm3 D. 1.78 dm3
(a) Outline two features of this experiment that ensure that the propanal intermediate is not a major product.