Given:
Half life(t^ 1/2) :30 years
A0( initial mass of the substance): 200 mg.
Now we know that
A= A0/ [2 ^ (t/√t)]
Where A is the mass that remains after t years.
A0 is the initial mass
t is the time
t^1/2 is the half life
Substituting the given values in the above equation we get
A= [200/ 2^(t/30) ] mg
Thus the mass remaining after t years is [200/ 2^(t/30) ] mg
H2O became a vapor when heated because thats the only one that can go back to its normal state, which is what a physical change is.
Answer:
151.63 g
Explanation:
We first get the number of moles;
Moles = Molarity × volume
= 2.0 × 0.475
= 0.95 moles
1 mole of CuSO4 = 159.609 g/mol
Therefore;
Mass = moles × molar mas
= 0.95 moles × 159.609 g/mol
= 151.63 g
Answer:
Option B : burning of wood
Explanation:
Chemical change is a change where a new substance is created like when you will bur wood you get ash this is a new substance, so burning of wood is a chemical change.
