In chemistry, a solution is a homogeneous mixture composed of two or more substances. In such a mixture, a solute is a substance dissolved in another substance, known as a solvent.
I believe the best description comparing the structure of carbohydrates and nucleic acids would be A.
To determine the relative atomic mass of thallium, we multiply the molar mass of the isotopes to their corresponding relative abundance. The molecular percentages should sum up to 1. In this case, we multiply 203 by 0.295 and 205 by 0.705 and add the answers of the two. The final atomic mass is 204.41 g/mol.
I believe a solution of Sn(NO3)2 can not be stored in an aluminium container because Aluminium is higher in the reactivity series compared to Tin (Sn). Therefore, Aluminium is more reactive than Tin and hence aluminium will displace Tin from its salt forming Aluminium nitrate and Tin metal. Thus storing Tin nitrate in an aluminium container will cause the "eating away' of the container.