Answer:
The two elements are POLONIUM and RADIUM.
Explanation:
Maria Curie is a French physicist and chemist, though she was of a Polish naturals. She was the first woman to receive a Noble Price which she earned for conducting leading and head way research on radioactivity. She discovered the theory of radioactivity; also the techniques isolating radioactive isotopes. These helped her and her husband discover Polium and Radium.
Answer:
∴ The absolute pressure of the air in the balloon in kPa = 102.69 kPa.
Explanation:
- We can solve this problem using the general gas law:
<em>PV = nRT</em>, where,
P is the pressure of the gas <em>(atm)</em>,
V is the volume of the gas in L <em>(V of air = 6.23 L)</em>,
n is the no. of moles of gas <em>(n of air = 0.25 mole)</em>,
R is the general gas constant <em>(R = 0.082 L.atm/mol.K)</em>,
T is the temperature of gas in K <em>(T = 35 °C + 273 = 308 K</em>).
∴ P = nRT / V = (0.25 mole)(0.082 L.atm/mol.K)(308 K) / (6.23 L) = 1.0135 atm.
- <em>Now, we should convert the pressure from (atm) to (kPa).</em>
1.0 atm → 101.325 kPa,
1.0135 atm → ??? kPa.
∴ The absolute pressure of the air in the balloon in kPa = (101.325 kPa)(1.0135 atm) / (1.0 atm) = 102.69 kPa.
A machine called a barometer is what is used to measure atmospheric pressure :D
As the independent variable changes, the dependent variable never changes.
.3999 moles
The ideal gas law: PV = nRT
155 degrees Celsius = 428 Kelvins
n = PV/RT
n = 2.80 atm x 5.00 L/0.0821 (gas constant) x 428 K
= 0.398 moles