Answer:
true I just took the test this morning
The molarity of potassium ions in a 0.122 M K2CrO4 is 0.244 M
<u><em>Explanation</em></u>
write dissociation reaction for K2CrO4
that K2CrO4 (aq)→ 2K^+ (aq) + CrO4^2- (aq)
K2CrO4 dissociate to give 2 ions of potassium ,therefore the molarity of potassium ion = 2 x 0.122 = 0.244 M
Given :
A student has a 1 g sample of each of the following compounds: NaCl, KBr, and KCl.
To Find :
The samples in order of increasing number of moles in the sample.
Solution :
Molecular mass of NaCl, KBr, and KCl is 58.5 g/mol , 119 g/mol and
74.5 g/mol respectively .
Moles of NaCl , 
.
Moles of KBr , 
.
Moles of KCl , 
.
The order of moles in increasing order is :
KBr , KCl and NaCl .
Hence , this is the required solution .
To counter the removal of A the equilibrium change by <u>s</u><em>hifting toward the left</em>
<em> </em><u><em>explanation</em></u>
<u><em> </em></u>If the reaction is at equilibrium and we alter the condition a new equilibrium state is created
<u><em> </em></u>The removal of A led to the shift of equilibrium toward the left since it led to less molecules in reactant side which favor the backward reaction.( equilibrium shift to the left)
Molality is the number of moles of solute in 1 kg of solvent
number of moles of sucrose - mass of sucrose / molar mass
number of moles of sucrose - 34.2 g / 342.34 g/mol = 0.0999 mol
number of moles in 125 g of water - 0.0999 mol
therefore number of moles in 1000 g - 0.0999 / 125 x 1000 = 0.799 mol/kg
molality of sucrose solution - 0.799 mol/kg
