Answer: 17.78g
Explanation:
Assume there is no heat exchange with the environment, then the amount of heat taken by the steel rod, Q(s), is equal to the amount of heat lost by the water, Q(w), but with opposite sign.
Q(s) = -Q(w)
Remember, Q = mc(ΔΦ)
Where Q = amount of heat
m = mass of steel
c = specific heat capacity of steel
ΔΦ = Initial temperature T1 - Final temperature T2
Q = mc(T1-T2)
Recall, Q(s) = -Q(w). Then,
m(s)*c(s)*(T1s - T2s) = - m(w)*c(w)*(T1w - T2w)
Substituting each values
Note: m(w) = volume of water*density = 75mL*1g/mL = 75g
m(s)*0.452*(21.5-2) = -75*4.18*(21.5-22)
m(s)*8.814 = 156.75
m(s) = 156.75/8.814
m(s) = 17.78g
Therefore, the mass of steel is 17.78g
For getting the result of this problem, the knowledge of periodic table is very important. From the periodic table we come to know that. The knowledge of atomic mass of magnesium is also required to solve the problem.
1 mole of magnesium = 24.3 gm
88.1 moles of magnesium = (24.3 * 88.1) gms
= 2140.83 gms
So 2140.83 grams are there in 88.1 moles of magnesium.
Answer:D.
Explanation:i used photo math. It is really helpful when I'm doing math homework etc...
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