Which of these what?
This isn't clear, can you put the answer choice or something?
Answer:
Solvent
Explanation:
When one substance dissolves into another, a solution is formed. A solution is a homogeneous mixture consisting of a solute dissolved into a solvent
Answer:
Energy is absorbed, and an emission line is produced.
Explanation:
Electrons are present and revolving continuously in the orbits that are present around the nucleus. The energy of electron are fixed and unable to move to other orbits due to the strong attractive force of the proton which is present in the nucleus of the atom. If the electron wants to jump from the first energy level to the second energy level, so the electron has to absorb enough energy which can overcome the attractive force of proton.
1) 1 molecules
2) 2 oxygen atoms
3)2 moles of Al2O3 are formed
4)4:3
Answer : The time required for decay is, 84 days.
Explanation :
Half-life of chromium-51 = 28 days
First we have to calculate the rate constant, we use the formula :



Now we have to calculate the time required for decay.
Expression for rate law for first order kinetics is given by:

where,
k = rate constant
t = time taken by sample = ?
a = let initial activity of the sample = 100
a - x = amount left after decay process = 12.5
Now put all the given values in above equation, we get


Therefore, the time required for decay is, 84 days.