(4.184 J/g·°C) x (1000 g) x (28.0 - 12.0)°C = 66944 J required
(66944 J) / ((333 J/g) + ((4.184 J/g·°C) x (12.0 - 0)°C)) = 175 g ice
Answer:
H2SO4
Explanation:
Firstly,
2.056% hydrogen = 2.056g of H
32.69% Sulphur = 32.69g of S
65.26% oxygen = 65.26g of O
Next, we convert each mass into moles by dividing by their respective molar mass:
H = 1, S = 32, O = 16
H = 2.056/1 = 2.056mol
S = 32.69/32 = 1.021mol
O = 65.26/16 = 4.078mol
Next, we divide each mole value by the smallest mole value (1.021)
H = 2.056/1.021 = 2.01
S = 1.021/1.021 = 1
O = 4.078/1.021 = 3.99
Approximately the ratio of H to S to O is 2:1:4, hence, the empirical formula for H, S and O is H2SO4.
Lead is heavier and more resistant. Plastic foam is light and can easily be broken
Answer:
0.081g
Explanation:
first step:calculate the molar conc of the stock solution
molar conc=mass/molar mass ×1000/vol(ml)
molar mass of Co(N03)2=182.943
molar conc=3g/182.943 ×1000/100ml
=0.163M
To calculate the conc of the resulting solution we apply the dilution principle
n=cv
C1V1=C2V2
C1=conc of stock solution=0.163M
V1=4mL
V2=275ml(final volume)
by making 'C2" the subject C2=0.163×4/275
=0.0024M
by applying the formular for calculating molar conc of a solution,we can calculate the mass of CO(NO3)2 in the reulting solution
molar conc=mass/molar mass ×1000(L)/vol(mL)
mass=0.0024×182.943×275/1000
=0.1193g
Mass of CO(NO3)2 in the resulting solution=0.1199g
since CO+(NO3)2=CO(NO3)2
Percentage by mass of (NO3)2 in CO(NO3)2=(NO3)2/CO(NO3)2
=124/182.943×100
=67.8%
it means 67.8% of 0.1193g is the mass of (NO3)2=0.678×0.1199
=0.081g