Question

QUESTION 9 Which of the following ions is most likely to form an insoluble sulfate? O a. Lit Oh- Ba 2+ Oc. Nat e. Br- am (K.mol), 1 atm 760 mmHg) QUESTION 10 What is the pressure of a 20.8-L gas sample containing 3 mol of gas at 20°C? (R=0.0821 L a. 3.46 mmHg b.4.12 x 103 mmHg 06. 2.63 x 103 mmHg d. 2.67 x 103 mmHg € 1.08 x 102 mmHg

Answer 1

9)

Salt of alkali metals are soluble

So, Li2SO4 is soluble

BaSO4is not soluble

Salt of alkali metals are soluble

So, Na2SO4 is soluble

Se2- and Br- are anion.

They will not form compound.

Answer: b

10)

Given:

V = 20.8 L

n = 3 mol

T = 20.0 oC

= (20.0+273) K

= 293 K

use:

P * V = n*R*T

P * 20.8 L = 3 mol* 0.08206 atm.L/mol.K * 293 K

P = 3.4678 atm

= 3.4678 * 760 mmHg

= 2.63*10^3 mmHg

Answer: c