Answer:
Explanation:
we know that specific heat is the amount of heat required to raise the temperature of substance by one degree mathmeticaly
Q=mcΔT
ΔT=T2-T1
ΔT=26.8-10.2=16.6
C for water is 4.184
therefore
Q=1.00*4.184*16.6
Q=69.4 j
now we have to covert joule into calorie
1 calorie =4.2 j
x calorie=69.4 j/2
so 69.4 j =34.7 calorie thats why 34.7 calorie heat is required to raise the temperature of water from 10.2 to 26.8 degree celsius
Molarity is defined as the moles of solute per liter of solution. 
. Where M is molarity, n is the number of moles and V is the volume. First we must find the molar mass of 
which is 109.98 g/mol
Then we find the molarity using above equation
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Here is the link to a great video that explains your question nicely, hope this helps.
N(C)=5,02·10²² atoms
calculation check:
N(C)=(1/12)*6.022*10²³=0.5018*10²³≈5.02·10²²
