[thomas49th]

Q) What mass of potassium carbonate would be formed when 10g of potassium hydrogencarbonate are completely decomposed.

KHCO₃ -> K₂CO₃ + H₂O + CO₂
Calculate KHCO₃ and K₂CO₃
KHCO₃  = 39 + 1 + 12 + 3(16) = 100g
K₂CO₃ = 2(39) + 12 + 3(16) = 138g

 BALANCE IT

2 moles of KHCO₃ gives 1 mole of K₂CO₃ and 1mole H₂O and 1 mole of CO₂

200g of KHCO₃  gives 138g of K₂CO₃

10g of KHCO₃  gives 2(138/100 x 10) KHCO₃ (2 as it's 2 moles)

10 of KHCO₃  gives 13.8g of KHCO₃

Is that right?

[Borek]

Check your math.

[thomas49th]

THhen my revision guide is wrong . I got 6.9 first, but i checked the answer and it was 13.8, so I thought i'd have to double it for the mols, but I had already doubled the M_r to get 200g. That's why I came here

Thanks

p.s Where did you get that software from?

[Borek]

EBAS. See my signature