C would be the correct answer
Answer:
0.045 M/s
Explanation:
Given:
Initial concentration of A = 0.625 M
Final concentration of A = 0.100 M
Total time taken for the change of concentration = 11.6 seconds
The average rate of reaction is calculated as:
= 
on substituting the respective values, we get
= 
or
The average rate of reaction = 0.045 M/s
Answer:
70g of Pb(NO3)2 would need to be added
Explanation:
As you can see in the solubility graph of lead nitrate, Pb(NO₃)₂, the solubility of this salt (That is, the maximum amount of the salt that can be dissolved in 100g of the solvent producing a homogeneous solution) is 70g in 100g of water = 70g of the salt in 100mL of water.
A saturated solution is also defined as solubility: The maximum amount of a solute that can be dissolved in a solvent.
That means:
70g of Pb(NO3)2 would need to be added
https://www.khanacademy.org/science/chemistry/chemical-reactions-stoichiome/balancing-chemical-equations/v/balancing-chemical-equations-introduction
this will help trust me
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