Answer:
12.50g
Explanation:
T½ = 2.5years
No = 100g
N = ?
Time (T) = 7.5 years
To solve this question, we'll have to find the disintegration constant λ first
T½ = In2 / λ
T½ = 0.693 / λ
λ = 0.693 / 2.5
λ = 0.2772
In(N/No) = -λt
N = No* e^-λt
N = 100 * e^-(0.2772*7.5)
N = 100*e^-2.079
N = 100 * 0.125
N = 12.50g
The sample remaining after 7.5 years is 12.50g
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The mass of solid lead would displace exactly 234.6 liters of water should be <span>2,674,440</span>
We all know, Density = Mass/ volume.
When volume increases and the mass remains the same , the density will decrease considerably.
Answer:
82.0343 g/mol
Explanation:
Count each element and the number of atoms for each element. Add them all together. Use the periodic table.
The pebbles become smooth and even because of erosion. the waves from the sea rub against the pebbles this is erosion. x