Answer:
C
Explanation:
Think of 'exo' as exit and 'thermic' as relating to thermal energy/ heat. Thus, an exothermic release thermal energy as the reaction proceeds.
In an exothermic reaction, the total energy of the products is lesser than that of the reactants and ΔH (change in energy) is less than zero.
When heat is absorbed as the reaction proceeds, the chemical reaction is an endothermic reaction.
CuO+ H2SO4 = CuSO4 + H2O
Redox reaction because both oxidation and reduction is occurring. Cu reducing agent and H2 oxidating
The answer is B 5.40 x 10^14 Hz
The correct answer is both newlands and mendeleev arranged elements according to their atomic masses, but only mendeleev used chemical properties as well.
The explanation:
1- Newlands arranged all the elements known at the time into a table in order of relative atomic mass. ... He then put the similar elements into vertical columns, known as groups.
2- Mendeleev also arranged the elements known at the time in order of relative atomic mass, but he did some other things that made his table much more successful.
He realised that the physical and chemical properties of elements were related to their atomic mass in a 'periodic' way, and arranged them so that groups of elements with similar properties fell into vertical columns in his table.
There should be 22 figures .