Given 482 milliliters of a gas at 37 degrees Celsius and at 1.3 atmospheres, how many moles of gas are present? (The ideal gas constant is 0.0821 L · atm/mol · K.)

2.46 x 101 moles

2.06 x 100 moles

2.06 x 10-1 moles

2.46 x 10-2 moles

The number of moles gas = 2.46 *10^-2 moles

Explanation:

Step 1: Data given

Volume = 482 mL = 0.482 L

Temperature = 37 °C

Pressure = 1.3 atm

The gas constant = 0.08206 L*atm/mol*K

Step 2: Calculate the number of moles of gas

pV = nRT

⇒with p =the pressure of the gas = 1.3 atm

⇒with V = the volume of the gas = 0.482 L

⇒with n = the number of molesgas= TO BE DETERMINED

⇒with R = the gas constant = 0.0821 L*atm/mol*K

⇒with T = the temperature = 37°C = 310 K

n = (pV)/(RT)

n = (1.3*0.482)/(0.0821*310)

n= 0.0246 moles = 2.46 *10^-2 moles

The number of moles gas = 2.46 *10^-2 moles

answer: c. the experiment shows that the red substance experienced a chemical change.

explanation: chemical change is the change in which chemical composition of the substance changes. physical change is the change in which there is no change in chemical composition.

chemical changes are accompanied by following changes:

a) precipitate formation

b) energy is released or absorbed

c) formation of bubbles

d) change in color

as it is given that the red color has disappeared and there is production of gas, it means the red substance has undergone a chemical change.

e