Answer:
0.07 g/s.
Explanation:
From the question given above, the following data were obtained:
Mass lost = 9.85 g
Time taken = 2 min 30 s
Mean rate =?
Next, we shall convert 2 min 30 s to seconds (s). This can be obtained as follow:
1 min = 60 s
Thus,
2 min = 2 × 60 = 120 s
Therefore,
2 min 30 s = 120 s + 30 s = 150 s
Finally, we shall determine the mean rate of the reaction. This can be obtained as illustrated below:
Mass lost = 9.85 g
Time taken = 150 s
Mean rate =?
Mean rate = mass lost / time taken
Mean rate = 9.85 / 150
Mean rate = 0.07 g/s
Therefore, the mean rate of the reaction is 0.07 g/s
Answer:
168°C is the melting point of your impure sample.
Explanation:
Melting point of pure camphor= T =179°C
Melting point of sample = 
= ?
Depression in freezing point = 
Depression in freezing point is also given by formula:
= The freezing point depression constant
m = molality of the sample = 0.275 mol/kg
i = van't Hoff factor
We have: = 40°C kg/mol
i = 1 ( non electrolyte)
168°C is the melting point of your impure sample.
Answer:
H2O is a compound because its a main constitute of earths hydrosphere
Answer:
4.48 - 6.48
Explanation:
A pH indicator works in a better way in a range of pH = pKa ± 1. That means we need to determine the pKa of the indicator propyl red to find the range over which it change its color. That is:
pKa = -log Ka
pKa = -log 3.3x10⁻⁶
pKa = 5.48
That means the range over propyl red will change from yellow to red or vice versa is:
4.48 - 6.48
