Explanation:
A volatile substance is defined as the substance which can easily evaporate into the atmosphere due to weak intermolecular forces present within its molecules.
Whereas a flammable substance is defined as a substance which is able to catch fire easily when it comes in contact with flame.
Hence, when we heat a flammable or volatile solvent for a recrystallization then it should be kept in mind that should heat the solvent in a stoppered flask to keep vapor away from any open flames so that it won't catch fire.
And, you should ensure that no one else is using an open flame near your experiment.
Thus, we can conclude that following statements are correct:
- You should heat the solvent in a stoppered flask to keep vapor away from any open flames.
- You should ensure that no one else is using an open flame near your experiment.
Answer:
0.33 mol
Explanation:
Given data:
Volume of balloon = 8.3 L
Temperature = 36°C
Pressure = 751 torr
Number of moles of hydrogen = ?
Solution:
Temperature = 36°C (27 +273 = 300 K)
Pressure = 751 torr (751/760= 0.988 atm)
Formula:
The given problem will be solve by using general gas equation,
PV = nRT
P= Pressure
V = volume
n = number of moles
R = general gas constant = 0.0821 atm.L/ mol.K
T = temperature in kelvin
PV = nRT
0.988 atm × 8.3 L = n × 0.0821 atm.L/ mol.K ×
300 K
8.2 atm.L = n × 24.63 atm.L/ mol
n = 8.2 atm.L / 24.63 atm.L/ mol
n = 0.33 mol
an amorphous solid because the particles do not have a regular structure is the answer
Answer:
Zero
Explanation:
FrBr is an ionic compound
.
Fr is in Group 1. Br is in Group 17.
The charges on the ions are +1 and -1, respectively.
The compound consists of Fr⁺Br⁻ ions.
However, there are equal numbers of + and - charges, so
The overall charge of the compound is zero.
The final temperature of the water is the equilibrium temperature, or the also the final temperature of the iron after a long period of time. Applying the conservation of energy:
m,iron*C,iron*ΔT = - m,water*C,water*ΔT
The density of water is 1000 g/mL.
(25 g)(0.449 J/g·°C)(T - 398 K) = - (25 mL)(1000 g/mL)(4.18 J/g·°C)(T - 298)
Solving for T,
<em>T = 298.01 K</em>
