<u>Given:</u>
Dimensions of the room= 12 ft * 15 ft * 8.60 ft
<u>To determine:</u>
The amount of HCN that gives the lethal dose in the room with the given dimensions
<u>Explanation:</u>
As per the World Health Organization, the lethal dose of HCN is around 300 ppm
300 ppm = 300 mg of HCN/ kg of inhaled air
Volume of air = volume of room = 12 * 15 *8.6 = 1548 ft³
Now, 1 ft³ = 28316.8 cm³
Therefore, the calculated volume of air corresponds to:
1548 * 28316.8 = 4.383 * 10⁷ cm3
Density of air (at room temperature 25 C) = 0.00118 g/cm3
Thus mass of air corresponding to the calculated volume is
Mass = Density * volume = 0.00118 g/cm3 * 4.383 * 10⁷ cm3
= 5.172*10⁴ g = 51.72 kg
Lethal amount of HCN corresponding to 51.72 kg of air would be.
= 51.72 kg air* 300 mg of HCN/1 kg air = 15516 mg
Ans: Lethal dose of HCN = 15.5 g
Answer: The yield of dibromide product will be approximately one‑half of the expected yield.
Explanation:
Hey there!:
ΔTf = Kf * m
Molar mass glucose = 180 g/mol
number of moles glucose:
n = mass of solute / molar mass
n = 21.5 / 180
n = 0.119 moles glucose
Amount of solvent in kg = 255/1000 = 0.255 Kg
Molality = number of moles / solvent
m = 0.119 / 0.255
m = 0.466 moles/kg
Kf for water = - 1.86 ºC/*m
Therefore:
ΔTf = Kf * m
ΔTf = (-1,86) * 0.466
ΔTf = -0.86676 ºC
hope this helps!
Answer:
108.6 g
Explanation:
- 2NaN₃(s) → 2Na(s) + 3N₂(g)
First we use the <em>PV=nRT formula</em> to <u>calculate the number of nitrogen moles</u>:
- R = 0.082 atm·L·mol⁻¹·K⁻¹
- T = 0 °C ⇒ 0 + 273.2 = 273.2 K
<u>Inputting the data</u>:
- 1.00 atm * 56.0 L = n * 0.082 atm·L·mol⁻¹·K⁻¹ * 273.2 K
Then we <u>convert 2.5 moles of N₂ into moles of NaN₃</u>, using the <em>stoichiometric coefficients of the balanced reaction</em>:
- 2.5 mol N₂ *
= 1.67 mol NaN₃
Finally we <u>convert 1.67 moles of NaN₃ into grams</u>, using its <em>molar mass</em>:
- 1.67 mol * 65 g/mol = 108.6 g
Because the helium inside it is lighter than air , hence it rises up
The balloon from our breath contains carbon dioxide which is heavier than air so it doesn’t rise