Helium is a very important element for both industrial and research applications. In its gas form it can be used for welding, and since it has a very low melting point (only 0.95 K under 2.5 MPa) it can be used in liquid form to cool superconducting magnets, such as those found in particle physics experiments. Say we have a cylinder of n = 125 moles of Helium gas at room temperature (T = 20° C). The cylinder has a radius of r = 17 cm and a height h = 1.64 m. What pressure is Helium gas under?

P = 20.1697 atm

Explanation:

In this case we need to use the ideal gas equation which is:

PV = nRT (1)

Where:

P: Pressure (atm)

V: Volume (L)

n: moles

R: universal gas constant (=0.082 L atm / K mol)

T: Temperature

From here, we can solve for pressure:

P = nRT/V  (2)

According to the given data, we have the temperature (T = 20 °C, transformed in Kelvin is 293 K), the moles (n = 125 moles), and we just need the volume. But the volume can be calculated using the data of the cylinder dimensions.

The volume for any cylinder would be:

V = πr²h  (3)

Replacing the data here, we can solve for the volume:

V = π * (17)² * 164

V = 148,898.93 cm³

This volume converted in Liters would be:

V = 148,898.93 mL * 1 L / 1000 mL

V = 148.899 L

Now we can solve for pressure:

P = 125 * 0.082 * 293 / 148.899

answer: e.   sour taste

explanation: acids are those substances which dissociates in water to give ions. as they dissociate to give ions, they act as electrolytes and thus are electrically conductive. acids are sour in taste. example: hcl

bases are those substances which dissociates in water to give ions or accepts ions. as they dissociate to give ions, they act as electrolytes and thus are electrically conductive. bases are bitter in taste. bases are slippery in nature.