Answer:
0.46 grams (C₆H₅)₂CO
Explanation:
To find the mass of benzophenone ((C₆H₅)₂CO), you need to (1) convert mmoles to moles and then (2) convert moles to grams (via molar mass). It is important to arrange the conversions/ratios in a way that allows for the cancellation of units. The final answer should have 2 sig figs to match the sig figs of the given value (2.5 mmoles).
Molar Mass ((C₆H₅)₂CO): 13(12.011 g/mol) + 10(1.008 g/mol) + 15.998 g/mol
Molar Mass ((C₆H₅)₂CO): 182.221 g/mol
2.5 mmoles (C₆H₅)₂CO 1 mole 182.221 g
----------------------------------- x ------------------------ x ------------------- =
1,000 mmoles 1 mole
= 0.46 grams (C₆H₅)₂CO
Answer:
The chronic daily intake during the period of exposure is most nearly 0.012 mg/kg day.
Explanation:
Number of hours worker exposed to xylene = 
The concentration of xylene in the workplace =
The worker is inhaling air at a rate of 
.
Amount xylene inhaled by worker in an hour :
= 
Amount xylene inhaled by worker in 320 hours:
1 μg = 0.001 mg
Amount xylene inhaled by worker in 320 hours = 11.520 mg
1 day = 24 hours
Amount xylene inhaled by worker in 1 day:
Assuming 70 kg body mass, the chronic daily intake of xylene :
The chronic daily intake during the period of exposure is most nearly 0.012 mg/kg day.
Answer:
3.01 × 10^24 particles
Explanation:
According to Avagadro, in one mole of a substance, there are 6.02 × 10^23 atoms or particles.
Using the formula: N = n × NA
Where;
N= number of particles or atoms
n = number of moles
NA = Avagadro's constant or number
This means that for 5 moles of a substance, there will be:
5 × 6.02 × 10^23
= 30.1 × 10^23
= 3.01 × 10^24 particles
The volume of H₂ : = 15.2208 L
<h3>Further explanation</h3>
Given
Reaction
2 As (s) + 6 NaOH (aq) → 2 Na₃AsO₃ (s) + 3 H₂ (g)
34.0g of As
Required
The volume of H₂ at STP
Solution
mol As (Ar = 75 g/mol) :
= mass : Ar
= 34 g : 75 g/mol
= 0.453 mol
From the equation, mol ratio As : H₂ = 2 : 3, so mol H₂ :
=3/2 x mol As
=3/2 x 0.453
= 0.6795
At STP, 1 mol = 22.4 L, so :
= 0.6795 x 22.4 L
= 15.2208 L
