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sweet-ann [11.9K]
3 years ago
10

Hello :) how to do this?

Chemistry
2 answers:
Nina [5.8K]3 years ago
7 0

Answer:

i dk

Explanation:

juin [17]3 years ago
4 0

Answer:

28g/ dm³

0.5 M

Explanation:

1dm³= 1000cm³

Let's convert the volume to cm³.

Volume of solution

= 200cm³

= (200÷1000) dm³

= 0.2 dm³

Concentration in g/dm³ means the amount of solute, KOH, in 1 dm³ of solution.

In 0.2 dm³, there is 5.6g of KOH.

Thus in 1 dm³, amount of KOH

= 5.6 ÷0.2

= 28g

Concentration in g/dm³ is 28g/dm³.

Molarity is a concentration unit. It is the number of moles of solvent in 1 L or 1dm³ of solution. Since we have already found the mass of KOH in 1dm³ of solution, we will use dm³.

1dm³ ----- 28g of KOH

moles= mass ÷mr

Molecular mass of KOH

= 39 +16 +1

= 56

1dm³ ----- 28 ÷56= 0.5 moles of KOH

Thus, concentration in molarity is 0.5M.

(Unit for molarity is M)

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At 350°c, keq = 1.67 × 10-2 for the reversible reaction 2hi (g) ⇌ h2 (g) + i2 (g). what is the concentration of hi at equilibriu
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