To solve this, we can use two equations.
t1/2 = ln 2 / λ = 0.693 / λ
where, t1/2 is half-life and λ is the decay constant.
t1/2 = 10 min = 0.693 / λ
Hence, λ = 0.693 / 10 min - (1)
Nt = Nο e∧(-λt)
Nt = amount of atoms at t =t time
Nο= initial amount of atoms
t = time taken
by rearranging the equation,
Nt/Nο = e∧(-λt) - (2)
From (1) and (2),
Nt/Nο = e∧(-(0.693 / 10 min) x 20 min)
Nt/Nο = 0.2500
Percentage of remaining nuclei = (nuclei at t time / initial nuclei) x 100%
= (Nt/Nο ) x 100%
= 0.2500 x 100%
= 25.00%
Hence, Percentage of remaining nuclei is 25.00%
Answer:
118.776 mmHg
Explanation:
The equation of the reaction is;
C4H10(g) + 13/2 O2(g) ------> 4CO2(g) + 5H20(g)
Now the mole ratio according to the balanced reaction equation is;
1 : 6.5 : 4 : 5
Hence, the total number of moles present = 1 + 6.5 + 4 + 5 = 16.5 moles
Mole fraction of water vapour = 5/16.5 = 0.303
We also know that;
Partial pressure= mole fraction * total pressure
Partial pressure of H20(g) = 0.303 * 392 mmHg = 118.776 mmHg
Answer:
The full amount (5.00 g) will be dissolved in 1 L of water at 25°C.
Explanation:
The molecular weight (MW) of Vanillin (C₈H₈O₃) is calculated from the chemical formula as follows:
MW(C₈H₈O₃) = (12 g/mol x 8) + (1 g/mol x 8) + (16 g/mol x 3) = 152 g/mol
If 0.070 mol of C₈H₈O₃ are soluble per liter of water at 25°C, the maximum mass that can be dissolved in 1 L is:
0.070 mol x 152 g/mol = 10.64 g
Since 5.00 g is lesser than the maximum amount that can be dissolved (10.64 g), the added amount will be completely dissolved in 1 L of water at 25°C.
Answer:
11.3 g of 
are produced from 36.0 g of 
Explanation:
1. The balanced chemical equation is the following:
2. Use the molar mass of the , the molar mass of the and the stoichiometry of the balanced chemical reaction to find how many grams of are produced:
Molar mass = 18
Molar mass = 17
Therefore 11.3 g of are produced from 36.0 g of
42- 8 = 34 sand dunes must be the answer
hope so it helps
