According to the reaction XCl2 (aq)+ (NH4)2S (aq) →XS(s) + 2NH4Cl (aq) The ppt XS has black color so the cation X is cation of

a-Silver

b- Nickel

c- Aluminum

d-Scandium

the role of the microscope world in creating new materials .

"standard molar enthalpy:

h2o ( liquid water ) : - 285.8 kj/mole

h2o ( water vapor ) : - 241.8 kj / mole.

δhrxn = - 241. 8 - ( - 285.8 )= -241.8 + 285.8 = 44.0

answer: 44.0 kj"

consider the reaction below.

 no rx

at 500 k, the reaction is at equilibrium with the following concentrations.

[pci5]= 0.0095 m

[pci3] = 0.020

[ci2] = 0.020 m

what is the equilibrium constant for the given reaction?

0.042

0.42

2.4

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