M = molar mass of the helium gas = 4.0 g/mol
m = mass of the gas given = 18.0 g
n = number of moles of the gas
number of moles of the gas is given as
n = m/M
n = 18.0/4.0
n = 4.5 moles
P = pressure = 2.00 atm = 2.00 x 101325 Pa = 202650 Pa
V = Volume of balloon = ?
T = temperature = 297 K
R = universal gas constant = 8.314
Using the ideal gas equation
P V = n R T
(202650) V = (4.5) (8.314) (297)
V = 0.055 m³
Polypeptides contain more than 10 amino acids joined by peptide bonds.
Answer:
1. D. They can be a substance, material, object or source of energy.
2. B. The properties will be different.
3. C. When two reactants form one product, the reaction is spontaneous.
Answer:
b. The reflection of light from a smooth surface is called specular reflection.
c. The reflection of light from a rough surface is called diffuse reflection.
Explanation:
a. The angle of incidence is equal to the angle of reflection only when a ray of light strikes a plane mirror.
This is wrong: Based on law of reflection "The angle of incidence is equal to the angle of reflection when light strikes any plane surface" examples plane mirrors, still waters, plane tables, etc
b. The reflection of light from a smooth surface is called specular reflection.
This is correct
c. The reflection of light from a rough surface is called diffuse reflection.
This is correct
d. For diffuse reflection, the angle of incidence is greater than the angle of reflection.
This is wrong: the angle of incident is equal to angle of reflection. The only difference between this type of reflection and specular reflection, is that the normal for diffuse reflection is not parallel to each due to the rough surface in which the light incidents.
For specular reflection, the angle of incidence is less than the angle of reflection.
This is wrong: the angle of incident is equal to angle of reflection
Answer:
New_momentum = 750 [kg.m/s]
Explanation:
Momentum is defined as
M = mass* velocity
Original momentum
M_old = 100 Kg * 5 m/s = 500 [kg.m/s]
If the car pulls over and picks up two people. The mass of the car is now 150 kg, but the velocity stays the same.
New momentum
M_new = 150 Kg * 5 m/s = 750 [kg.m/s]
