Question

How many grams of potassium chloride must decompose to produce 69.9 milliliters of potassium metal, if the density of potassium is 1.78 g/mL? Show all steps of your calculation as well as the final answer.

KCl → K + Cl2

Answer 1

@Abmon98 can u help me?

Answer 2

Density= mass/volume
you are given density and volume so find Mass

Answer 3

convert volume to Liters beforehand

Answer 4

ah no don't do it since in unit of density its mL

Answer 5

just put the values into the formula and get the mass

Answer 6

after you get mass of Potassium
use formula
mole= mass/Molecular mass
and get mole of Potassium

Answer 7

but first don't i have to get hte balanced equation? Which is 2K+Cl2=2KCl

Answer 8

after you get mole of potassium
balance the reaction and look at ratio between K and KCl

Answer 9

is it clear till now?

Answer 10

afterwards by ratio you will find mole of KCl
and as you find the mole
use formula
mole= mass/Molecular mass
and make mass as subject
mass= mole* Molecular mass
and find mass of KCl

Answer 11

more clear. thank you

Answer 12

you are welcome :))

Answer 13

Balance Chemical equation
2KCl-->2K+Cl2
Number of moles=Mass(g)/Molar Mass
Density=Mass/Volume
Mass=Density*Volume
1.78*69.9=124.422 grams produced.
Number of Moles 124.422/39.1=3.18
Look at the mole ratio of KCL to K its 2:2 they share the same number of moles
Mass=Number of Moles*Molar Mass
3.18*(39.1*1)+(35.5*1)
3.18*74.6=237 grams

Answer 14

awesome job @Abmon98 !! but don't do the whole calculation, @superhelp101 has to do it :)

Answer 15

wow that you guys!:-) don't worry i will do the calculation once myself :)

Answer 16

thank you :) @somy and i wont again sorry @superhelp101

Answer 17

you're fine

Answer 18

:]