Answer: 0.035 moles FeF3 or 3.5x10-² moles FeF3
Explanation: 1 mole of FeF3 is equal to its molar mass ( 113g FeF3)
4.0g FeF3 x 1 mole FeF3 / 113 g FeF3 = 0.035 moles of FeF3
The dilution formula can be used to find the volume needed
c1v1 = c2v2
Where c1 is concentration and v1 is volume of the concentrated solution
And c2 is concentration and v2 is volume of the diluted solution to be prepared
c1 - 0.33 M
c2 - 0.025 M
v2 - 25 mL
Substituting these values in the equation
0.33 M x v1 = 0.025 M x 25 mL
v1 = 1.89 mL
Therefore 1.89 mL of the 0.33 M solution needs to be diluted up to 25 mL to make a 0.025 M solution
Answer: Between 1 and 2.
Explanation:
Half life is the amount of time taken by a radioactive material to decay to half of its original value.
............(1)
where,
a = amount of reactant left after n-half lives = 40
= Initial amount of the reactant = 100
n = number of half lives
Putting in the values we get:

taking log on both sides


Thus half-lives that have elapsed is between 1 and 2
Answer:
6
Explanation:
p orbital can hold up to six electron. Argon electron configuration will be 1s²2s²2p⁶3s²3p⁶