Answer:
Rf = 0.26
Explanation:
The Rf value is calculated by dividing the distance traveled by a compound, by the distance traveled by the solvent front. In other words, the length of the TLC plate is not relevant in calculating a Rf value.
- Distance traveled by compound C = 18 mm
- Distance traveled by the solvent front = 70 mm
Answer: 6.58g
Explanation: We are to find the mass of NaCl that can produce 15% solution in a 750ml
STEP 1:
the reaction moles
NaCl + H2O = NaOH + HCl
Therefore 1mole of NaCl reacts with 1mole of H2O
STEP 2:
convert 750ml to liter
750ml × 1L/1000ml = 0.750L
STEP3 :
convert percentage concentration to mol/L
15% = 0.15mol/L
STEP 4:
find the mole
Mole= concentration× volume
0.15mol/L × 0.75L =0.1125mol
STEP 5 :
Find the mass
Mass = mole × molar mass
The molecular mass of NaCl is 23+35.5= 58.5g/mol
Therefore:
0.1125mol × 58.5g/mol = 6.58g
Approximately: 6.6g
Answer: 17.5
explanation: multiply 3.5 by 5 and you will get 17.5
Answer:
802.2 K
Explanation:
To solve this problem we can use the formula:
Where Tb is the boiling point (in K).
We already know the values of both ΔHvap and ΔSvap, so we calculate Tb:
- ΔHvap = 47.45 kJ·mol⁻¹ = 47.45x10³J·mol⁻¹
Tb = 47.45x10³J·mol⁻¹/59.15 J·mol⁻¹·K⁻¹
So the boiling point of the compound is 802.2 K (or 529 °C)
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