Answer:
D.
Explanation:
I took this test as a freshman and this was the only question of 4 that I can remember
Answer:
Let the mixture is X% by mass of CuSO
4
.5H
2
O and 100 - X % by mass of MgSO
4
.7H
2
O. 5.0 g of mixture will contain 0.05X g CuSO
4
.5H
2
O and 5.0 - 0.05X g MgSO
4
.7H
2
O
The molar masses of CuSO
4
.5H
2
O and MgSO
4
.7H
2
O are 249.7 g/mol and 246.5 g/mol respectively.
The number of moles of CuSO
4
.5H
2
O=
249.7
0.05X
=2.00×10
−4
X moles.
Explanation:
Pls mark it as branliest answere thanks
Answer: Hydrogen
Explanation: Im pretty sure its Hydrogen since P is the cathode and it has a - charge meaning positively charged ions will be attracted to it and Hydrogen is the only gas with a positive charge in the answers.
Answer : The time taken for the reaction is, 28 s.
Explanation :
Expression for rate law for first order kinetics is given by :
![k=\frac{2.303}{t}\log\frac{[A_o]}{[A]}](https://tex.z-dn.net/?f=k%3D%5Cfrac%7B2.303%7D%7Bt%7D%5Clog%5Cfrac%7B%5BA_o%5D%7D%7B%5BA%5D%7D)
where,
k = rate constant = 0.0632
t = time taken for the process = ?
![[A_o]](https://tex.z-dn.net/?f=%5BA_o%5D)
= initial amount or concentration of the reactant = 1.28 M
![[A]](https://tex.z-dn.net/?f=%5BA%5D)
= amount or concentration left time 't' = 
Now put all the given values in above equation, we get:
Therefore, the time taken for the reaction is, 28 s.
