In an experiment, 25.0 mL of a gas with a pressure of 1.00 atm is contained in a
ID: 957061 • Letter: I
Question
In an experiment, 25.0 mL of a gas with a pressure of 1.00 atm is contained in a balloon at 25.00 degree C. The balloon's temperature is adjusted until the pressure is 0.750 atm at a volume of 31.1 mL. What is the final temperature of the gas under the new conditions? 23.3degree C -93.4degreeC -46.4 degree C 5.02degrees C 46.4 degrees C Which one of the ionic compounds below would you expect to have the smallest (least negative) lattice energy?MgF_2 MgCl_2 d. MgBr_2 Mgl_2 Cal_2 Which of the solutions shown here will have the highest vapor pressure? White circles indicate solvent molecules; black circles indicate molecules of a nonvolatile solute.Explanation / Answer
Given:
vol. gas = 25.0 mL =0.025 L
Press gas = 1.0 atm
T= 25.0 deg C
T in K = 25.0 +273.15 = 298.15 K
Gas in balloon:
Pressure P = 0.75 atm
Volume = 0.0311 L
There are two states of gas. First, p1 = 1.0 atm , V1 = 0.025 L, T1= 298.15 K
Second state in balloon
P2 = 0.75 atm , V = 0.0311 L
We have to find the Temperature in second state and for this calculation we use combined gas las
P1V1T1=P2V2T1
Rewriting above equation in terms of T2
T2 = P2V2T1/P1V1
= [(0.75 * 0.0311 * 298.15 )/(1.0 * 0.025 ) ] K
T = 278 K
T in deg C
T = 278 -273.15 = 5.02 deg C
So the Temperature of gas in balloon would be 5.020C
Q. 7
Ionic bonds are formed due to electrostatic force of attraction. Ions are charged species and when opposite charged ions combine there is formation of ionic bond. The energy that is required to separate these ions again is called as lattice energy.
For example NaCl is formed when sodium ion (Na+) and Chloride ion (Cl- ) combine. We need to break this bond so that ions are separated and the energy is needed to this separation or breaking the bond is the lattice energy of sodium chloride.
We can see that more the electronegativity of negative ion and more the charge of positive ion make bond stronger.
Electrostatic force = q1 x q2 / r2 , here q1 and q2 are the charges and r is the distance so we can make following points.
So the lattice energy depends on the charges and the electronegativity and the shape. Lets check in given example which will have more lattice energy.
From going down in the periodic table size of the ions is increasing.
We know the size of the Ca+ is greater than that of the Mg2+ ion so we can neglect all Mg compound and also iodine has largest size among all the anions. So the answer choice will be CaI2
Q. 8
Vapor pressure is colligative property and we know it is exclusively depends on the number of solute particles.
In diagram d, has relatively large number of black spot non volatile solute particles so it will have highest vapor pressure.
Ans : d
Related Questions
drjack9650@gmail.com
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.