Answer: Temperature and number of moles are the conditions which remain constant in Boyle's law.
Explanation:
Boyle's law states that at constant temperature the pressure of a gas is inversely proportional to the volume of gas.
Mathematically, it is represented as follows.
As equation for ideal gas is as follows.
PV = nRT
And, at constant temperature the pressure is inversely proportional to volume which also means that number of moles are also constant in Boyle's law.
Thus, we can conclude that temperature and number of moles are the conditions which remain constant in Boyle's law.
Answer
There is nothing like viscosity in solid because most of the solids usually have a rigid body. This is due to strong intermolecular forces. And it is due to this strong force between the molecules that they are unable to move and they remain fixed at their position. Some solids such as graphite which have layered structure, don't possess the property of viscosity, because of the strong force between the layers.
Explanation:
Viscosity is the property of a fluid that opposes the relative motion between two surfaces of the fluid that are moving at different velocities. In simple terms, viscosity means friction between the molecules of fluid.
FOR EXAMPLE
water is "thin", having a low viscosity, while vegetable oil is "thick" having a high viscosity
I think the best answer would be D. Dolphin!
Answer:- 0.800 moles of the gas were collected.
Solution:- Volume, temperature and pressure is given for the gas and asks to calculate the moles of the gas.
It is an ideal gas law based problem. Ideal gas law equation is used to solve this. The equation is:
PV=nRT
Since it asks to calculate the moles that is n, so let's rearrange this for n:

V = 19.4 L
T = 17 + 273 = 290 K
P = 746 mmHg
we need to convert the pressure from mmHg to atm and for this we divide by 760 since, 1 atm = 760 mmHg

P = 0.982 atm
R = 
Let's plug in the values in the equation to get the moles.

n = 0.800 moles
So, 0.800 moles of the gas were collected.
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