Q=hc A (Ts-Ta)
q = heat transfered per unit time
A= heat transfer area of the surface
hc= convective heat transfer coefficient of the process
Ts= temperature of the surface
Ta= temperature of the air
Answers:
1. B.)
2. Both A.) and B.)
3. A.)
Step-by-step explanation:
1. Ions in gas phase
A plasma is a gas consisting of electrons and positively charged ions.
Because the particles are ions and electrons, rather than neutral atoms or molecules as in ordinary gases, scientists consider a plasma to be a fourth state of matter<em>.</em>
2. Kinetic Molecular Theory
Both activities illustrate the postulate.
A.) If the particles are extremely small and far apart, most of the volume of a gas is empty space. That's why it's easy to push the plunger of a capped nozzle syringe containing a gas.
B.) If the particles are far apart, it's easy for a coloured gas to spread into an inverted jar placed on top of a jar containing the gas.
3. Hot air balloon
The high temperature in the balloon makes the gas molecules spread apart according to Charles's law, because this law describes how a gas will behave at constant pressure.
As the hot air escapes from the vent, the combined mass of balloon + hot air becomes less than the mass of cold air that it displaces, and the balloon rises.
B.) is <em>wrong</em>. Boyle's law applies only when both the number of moles and the temperature remain constant.
Answer:
4.99 × 10³ g/mol
Explanation:
Step 1: Given and required data
- Mass of the covalent compound (m): 62.4 g
- Volume of the solution (V): 1.000 L
- Osmotic pressure (π): 0.305 atm
- Temperature (T): 25°C = 298 K
Step 2: Calculate the molarity (M) of the solution
The osmotic pressure is a colligative pressure. For a covalent compound, it can be calculated using the following expression.
π = M × R × T
M = π / R × T
M = 0.305 atm / (0.0821 atm.L/mol.K) × 298 K
M = 0.0125 M
Step 3: Calculate the moles of solute (n)
We will use the definition of molarity.
M = n / V
n = M × V
n = 0.0125 mol/L × 1.000 L = 0.0125 mol
Step 4: Calculate the molar mass of the compound
0.0125 moles of the compound weigh 62.4 g. The molar mass is:
62.4 g/0.0125 mol = 4.99 × 10³ g/mol
I believe the answer is B. a fruit falling from a tree
