Answer:
The activity of 50mg of Sr is 
Explanation:
Every nuclear disintegration follows the first order rate, thus the half-life (t1/2) is 
where k is the constant of the reaction.
<em>Considering 1 year equals 3.15x107 seconds</em>
For Sr with t1/2 = 
, the constant of the reaction is
The activity (A) of a nucleus is 
where N is the number of nucleus. Sr molecular mass is 87.6g/mol and every mol contains 6.023x1023 atoms, thus
Therefore, the activity of 50mg of Sr is
Answer:
A chemical reaction is a process in which the chemical bonds of a substance are broken or rearranged. One or more substances are formed with different properties because of this chemical reaction. Examples of chemical reactions are rust, combustion, and oxidation.
Answer:
c it does not change the energy state
Explanation:
The answer is:
E per gram = 0.45 V
The explanation:
when MnO2 is the substance who oxidized here so, the oxidizing agent and the anode here is Li.
and when the molar mass of Li is = 7 g/mol
and in our reaction equation we have 1 mole of Li will give 3.15 V of the electrical energy
that means that :
7 g of Li gives → 3.15 V
So 1 g of Li will give→ ???
∴ The E per gram = 3.15 V / 7 g of Li
= 0.45 V
