Answer:
6.88 mg
Explanation:
Step 1: Calculate the mass of ³²P in 175 mg of Na₃³²PO₄
The mass ratio of Na₃³²PO₄ to ³²P is 148.91:31.97.
175 mg g Na₃³²PO₄ × 31.97 g ³²P/148.91 g Na₃³²PO₄ = 37.6 mg ³²P
Step 2: Calculate the rate constant for the decay of ³²P
The half-life (t1/2) is 14.3 days. We can calculate k using the following expression.
k = ln2/ t1/2 = ln2 / 14.3 d = 0.0485 d⁻¹
Step 3: Calculate the amount of P, given the initial amount (P₀) is 37.6 mg and the time elapsed (t) is 35.0 days
For first-order kinetics, we will use the following expression.
ln P = ln P₀ - k × t
ln P = ln 37.6 mg - 0.0485 d⁻¹ × 35.0 d
P = 6.88 mg
Answer:
The sun radiates energy in all directions.
Explanation:
Most of it dissipates into space, but the tiny fraction of the sun's energy that reaches Earth is enough to heat the planet and drive the global weather system by warming the atmosphere and oceans
The landscape region of Long Island is the Atlantic coastal plain.
Answer:
0.185moles
Explanation:
Given parameters:
Volume of O₂ = 49.8L
Unknown:
Number of moles of sucrose required = ?
Solution:
We can assume that the reaction takes place at standard temperature and pressure.
From this, we can find the number of moles of oxygen that reacted and extrapolate to that of sucrose.
Chemical equation;
C₁₂H₂₂0₁₁ + 120₂ → 12CO₂ + 11H₂0
Number moles = 
at STP
Number of moles of oxygen gas = 
= 2.22moles
12 moles of oxygen gas combines with 1 mole of sucrose
2.22 moles of oxygen gas will combine with 
= 0.185moles
