Answer:
the properties of three undiscovered elements is the correct answer.
Explanation:
After he completed his work Mendeleev predicted the properties of the undiscovered elements.
In the year 1871, Dmitri Mendeleev predicted the detailed existence and the properties of the three elements that are undiscovered and he gained tremendous fame.
He left the gap in the table to put the elements which are not identified at that time and by glancing at the physical and chemical properties of an element next to the gap, Mendeleev could predict the properties of the not discovered elements.
Heat
gained in a system can be calculated by multiplying the given mass to the
specific heat capacity of the substance and the temperature difference. It is
expressed as follows:<span>
Heat = mC(T2-T1)
When two objects are in contact, it should be that the heat lost is equal to what is gained by the other. From this, we can calculate things. We do as follows:
</span>Heat gained = Heat lost
mC(T2-T1) = - mC(T2-T1)
31.5C (102.4 - 32.5) = 103.5(4.18)(32.5 - 24.5)
C = 1.57 J/C-g
Hope this helps.
Answer:
1) synthesis MgI2
2) double replacement CuS + (HCl)2
3) double replacement, not sure ab the formula sorry
This is just addition. Put 2140.56 on top, line up 9.3456 under it appropriately. Doing this will give you the answer: 2149.9056
