Impure substance, because pure would be dirt from the earth
Answer:
The activation energy was reached was 10:45 a.m. The additional energy did not affect the reaction.
Explanation:
They have a sea of delocalised electrons which are free to move therefore they can carry a current
Explanation:
Molarity = mol/L or g/L
Data:
Mass>80.0g
Mr of CaCl2>111.1g/mol
V>500mL
Convert mL to Litres;. mole=g/Mr
1L=1000mL. =80g/111.1g/mol
x=500mL. =0.720072007mol
x=0.5L
Molarity= mole/volume
=0.720072007mol/0.5L
=1.440144014mol/L
=1.4401mol/L
Hope this helps. Depending on the question you can also find it in g/L but mol/L is safer.
Answer:
12.213 minutes will be taken for 120 g-Thalium-208 to decay to 75 grams.
Explanation:
Radioactive isotopes decay exponentially in time, the mass of the isotope (
), in grams, is described by the formula in time (
), in minutes:
(1)
Where:
- Initial mass of the isotope, in grams.
- Time constant, in minutes.
In addition, the time constant associated with the isotope decay can be described in terms of half-life (
), in minutes:
(2)
If we know that 
, 
and 
, then the time taken by the isotope is:
12.213 minutes will be taken for 120 g-Thalium-208 to decay to 75 grams.
