Answer is: volume of KBr is 357 mL.
c(KBr) = 0,716 M = 0,716 mol/L.
m(KBr) = 30,5 g.
n(KBr) = m(KBr) ÷ M(KBr).
n(KBr) = 30,5 g ÷ 119 g/mol.
n(KBr) = 0,256 mol.
V(KBr) = n(KBr) ÷ c(KBr).
V(KBr) = 0,256 mol ÷ 0,716 mol/L.
V(KBr) = 0,357 L · 1000 mL/L = 357 mL.
Answer:
Ensure that the glassware is designed for heating
Check that there are no cracks in the glassware
Inspect the hot plate for frayed cords
Explanation:
All except measuring the height and width of the glassware could cause hazards within the lab.
Explanation:
The given reaction equation will be as follows.

Now, number of atoms on reactant side are as follows.
Number of atoms on product side are as follows.
Therefore, this equation is balanced since atoms on both reactant and product sides are equal.
Thus, we can conclude that there is one sulfur atom in the products.
Answer:
Mass = 6.183 g
Solution:
Step 1: Calculate number of moles of Boric acid using following formula,
Molarity = Moles ÷ Volume
Solving for Moles,
Moles = Molarity × Volume
Putting Values,
Moles = 0.05 mol.L⁻¹ × 2.0 L
Moles = 0.1 mol
Step 2: Calculate Mass of Boric Acid using following formula,
Moles = Mass ÷ M.mass
Solving for Mass,
Mass = Moles × M.mass
Putting values,
Mass = 0.1 mol × 61.83 g.mol⁻¹
Mass = 6.183 g
Flask used to prepare this solution is called as Volumetric flask. Take 2 L volumetric flask, add 6.183 g of Boric acid and fill it to the mark with distilled water.
Answer:
The boiling point of water at 550 torr will be 91 °C or 364 Kelvin
Explanation:
Step 1: Data given
Pressure = 550 torr
The heat of vaporization of water is 40.7 kJ/mol.
Step 2: Calculate boiling point
⇒ We'll use the Clausius-Clapeyron equation
ln(P2/P1) = (ΔHvap/R)*(1/T1-1/T2)
ln(P2/P1) = (40.7*10^3 / 8.314)*(1/T1 - 1/T2)
⇒ with P1 = 760 torr = 1 atm
⇒ with P2 = 550 torr
⇒ with T1 = the boiling point of water at 760 torr = 373.15 Kelvin
⇒ with T2 = the boiling point of water at 550 torr = TO BE DETERMINED
ln(550/760) = 4895.4*(1/373.15 - 1/T2)
-0.3234 = 13.119 - 4895.4/T2
-13.4424= -4895.4/T2
T2 = 364.2 Kelvin = 91 °C
The boiling point of water at 550 torr will be 91 °C or 364 Kelvin