Answer:
Explanation:
count given by old sample = .97 disintegrations per minute per gram
count given by fresh sample = 6.68 disintegrations per minute per gram
Half life of radioactive carbon = 5568 years
rate of disintegration
dN / dt = λ N
In other words rate of disintegration is proportional to no of radioactive atoms present . As number reduces rate also reduces .
Let initial no of radioactive be N₀ and after time t , number reduces to N
N₀ / N = 6.68 / .97
Now



λ is disintegration constant
λ = .693 / half life
= .693 / 5568
= .00012446 year⁻¹
Putting the values in the equation above


1.929577 = .00012446 t
t = 15503.6 years .
Answer:
2
Explanation:
cause it is what it is :> mark me brainlest
I am pretty sure the answer is F
the combustibility of calcium is relitivly high
Answer:
Explanation:
A) In H2SO4, the oxidation number of H is , that of S is , and that of O is .
In H₂SO₄ the oxidation sate of H is +1 (H₂= +2) that of sulfur is +6 and O is -2 (O₄= -8)
In SO₄ the oxidation state is -2, because negative and positive charges are not equal. That's why two hydrogen atoms are attached with one SO₄ to balance the charge.
B) In CaSO4, the oxidation number of Ca is , that of S is . , and that of O is .
In CaSO₄ the oxidation sate of Ca is +2 that of sulfur is +6 and O is -2 (O₄= -8)
In SO₄ the oxidation state is -2, because negative and positive charges are not equal. That's why one calcium atoms is attached with one SO₄ to balance the charge.
C) In HF, the oxidation number of H is , and that of F is .
In HF the oxidation state of hydrogen is +1 and that of fluorine is -1. Both form ionic compound.