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A single dose of an antacid tablet contains 1.850 g of sodium hydrogencarbonate, NaHCO3, and 0.600 g of calcium carbonate, CaCO3. Stomach acid is hydrochloric acid. Mr(NaHCO3) = 84.01 and Mr(CaCO3) = 100.09 Determine the amount of…
Which change results in the greatest decrease in entropy? A. CaCO3(s) → CaO(s) + CO2(g) B. NaNO3(s) → Na+(aq) + NO3−(aq) C. H2O(l) → H2O(g) D. N2(g) + 3 H2(g) → 2 NH3(g)
Diclofenac, an anti-inflammatory drug, is often supplied as its sodium salt, which dissolves in water more readily than the diclofenac molecule itself. Circle the functional group that reacts with sodium hydroxide when this salt is prepared.
Standard enthalpy changes of reaction are provided for the following reactions. C(s) + O2(g) → CO2(g) ΔH⊖ = −394 kJ…
Which methods could be used to determine the rate of this reaction? CaCO3(s) + 2 HCl(aq) → CaCl2(aq) + H2O(l) + CO2(g) I. measuring the decrease in mass of the reaction mixture II. measuring the change in absorbance of light by the solution in a…
A student converts methyl 4-hydroxybenzoate (Mr = 152.15) into methyl 4-methoxybenzoate (Mr = 166.18) by replacing the hydrogen atom of the phenol group with a methyl group. The product was analysed in a mass spectrometer. Suggest how…
Which compound has the largest lattice enthalpy? A. KI B. NaBr C. MgO D. CaS
3-Methylcyclohexanol is a cyclic alcohol. Draw circles around all chiral carbon atoms in the structure.
The reaction between nitrogen monoxide and chlorine gives the following rate data at a certain temperature. 2 NO(g) + Cl2(g) → 2 NOCl(g) What is the overall order of the reaction? A. 0 B. 1 C. 2 D. 3
A buffer solution of pH 5.35 contains ethanoic acid and its conjugate base, the ethanoate ion. The pKa of ethanoic acid is 4.76. The concentration of ethanoic acid in the buffer is 1.50 × 10−2 mol dm−3. Calculate…