Answer:
Hello attached below is the data found in Aleks Data tab
answer :
i) N0
ii) N0
iii) YES , pH of highest solubility = 5
Explanation:
i) For CuBr
solubility does not change with pH hence answer = NO
ii) For MgCl2
solubility does not change with pH hence the answer = NO
iii) For Ba(OH) 2
Solubility does change with pH hence the answer = YES
and the pH at which the highest solubility will occur is = 5
attached below is the reason for the answers given
The mass decay rate is of the form

where
m₀ = 3000 g,the initial mass
k = the decay constant
t = time, years.
Because the half-life is 30 years, therefore

After 60 years, the mass remaining is

Answer: 750 g
The balanced chemical reaction is :

Number of moles of Na,
.
Now, from balance chemical reaction we can see that 1 mole of oxygen reacts with 4 moles of sodium.
So, number of moles of oxygen are :

So, amount of oxygen required is :

Therefore, 5.08 gram of oxygen will react with 14.6 gram of sodium.
Because of making the equestion to be more stable and form the best compound according to it's reactant.