Answer:
-0.93 °C; 100.26 °C
Step-by-step explanation:
(a) Freezing point depression
The formula for the freezing point depression ΔT_f is
ΔT_f = iKf·b
i is the van’t Hoff factor: the number of moles of particles you get from a solute.
For sucrose,
Sucrose (s) ⟶ sucrose (aq)
1 mole sucrose ⟶ 1 mol particles i = 1
ΔT_f = 1 × 1.86 × 0.50
ΔT_f = 0.93 °C
T_f = T_f° - ΔT_f
T_f = 0.00 – 0.93
T_f = -0.93 °C
(b) Boiling point elevation
The formula for the boiling point elevation ΔTb is
ΔTb = iKb·b
ΔTb = 1 × 0.512 × 0.50
ΔTb = 0.256 °C
Tb = Tb° + ΔTb
Tb = 100.00 + 0.256
Tb = 100.26 °C
Let us assume that the ring is a size 7 ring, which has a circumference of 54.3 millimeters. Converting this to centimeters, the circumference of the ring is:
54.3 mm = 5.43 cm
Now, we determine the number of gold atoms that will be present in this:
5.43 / 1 x 10⁻⁹
There will be 5.43 x 10⁹ atoms
We now determine the number of moles this is by:
one mole = 6.02 x 10²³ atoms
Moles = 5.43 x 10⁹ / 6.02 x 10²³
Moles = 9.01 x 10⁻¹⁵ moles
The molar mass of gold is 197 g/mol
The mass is 9.01 x 10⁻¹⁵ * 197
The mass of the strand is 1.76 x 10⁻¹² grams
Answer:
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Hope it helps....⋋✿ ⁰ o ⁰ ✿⋌(・o・)
From the fact that oxygen is in group 16 and carbon is in group 14, the structure of CO2 must be O=C=O. In methane, there is no bond between any of the hydrogen atoms. The structure of H2O2 is H–O–O–H.
Carbon is in group 14 hence it has four valence electrons and oxygen is in group 16 hence it has six valence electrons. This implies that each oxygen atom will share four electrons with carbon in a covalent bond to form the structure O=C=O.
In CH4, we know that carbon is tetravalent so it forms for bonds. Therefore, there is no bond between hydrogen atoms so it bonds with each hydrogen atom; hydrogen only forms one bond.
In H2O2, there is the peroxide ion that has the structure O-O. Hence, the correct structure of H2O2 is H–O–O–H.
Learn more: brainly.com/question/24775418
