In this case, according to the given information about the oxidation numbers anf the compounds given, it turns out possible to figure out the oxidation number of manganese in both MnI2, manganese (II) iodide and MnO2, manganese (IV) oxide, by using the concept of charge balance.
Thus, we can define the oxidation state of iodine and oxygen as -1 and -2, respectively, since the former needs one electron to complete the octet and the latter, two of them.
Next, we can write the following 
, since manganese has five oxidation states, and it is necessary to calculate the appropriate ones:
Next, we multiply each anion's oxidation number by the subscript, to obtain the following:
Thus, the correct choice is Manganese has an oxidation number of +2 in Mnl2 and +4 in MnO2.
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The molecular formula of sucrose is - C₁₂H₂₂O₁₁
molecular mass of sucrose - 342 g/mol
molarity of sucrose solution is 0.758 M
In 1 L solution the number of sucrose moles are - 0.758 mol
Therefore in 1.55 L solution, sucrose moles are - 0.758 mol/L x 1.55 L
= 1.17 mol
The mass of 1.17 mol of sucrose is - 1.17 mol x 342 g/mol = 4.00 x 10² g
The heat transfer just occurred is mainly conduction.
Conduction happens when two objects are in contact with each other. In the hotter object, the molecules and/or free electrons have a higher kinetic energy, thus they'll travel and collide into other molecules, resulting in spreading the energy to the other object.
The heat transfer happens until thermal equilibrium, where both objects have the same temperature and their molecules have the same kinetic energy rate.
In addition, radiation is also happening since everything that has a higher temperature than the environment is a net emitter. They release electromagnetic waves that turn out to be radiation. These occur even without the presence of air.
