- #1

dagg3r

- 67

- 0

Remember that: 1kg = 103 g and 1 m = 102 cm. Express your answer to 1 decimal place (don't include units).

what i did is

1.37g = 0.00137 kg

1cm^3 = 1*10^-6 ie (1/(10^3))

0.00137 / (1*10^-6) = 1370.0 kg/m^3 is that correct?

i don't think so looks so large hehehe maybe I am confused heh someone shed some light on that

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question 2

What mass of K2CO3 is needed to prepare 200 mL of a solution having a potassium ion concentration of 0.150 M? (molecular mass of K2CO3 = 138.2 g mol-1)

Hint: remember that 2 K+ ions are produced in the solution, so twice the conc of the original salt)

its a multiple choice answer i did the working out and got 2.07g is that correct?

ill show whawt i did

n(k2c03)=0.150*(200/1000L)=0.03 mol /2 = 0.015mol

0.015 * 138.2gmol^-1 = 2.0703g

i hope that's right please tell me if it is wrong or right ppl thanks