Which compound, when added to Iron(II) sulphate (aq) takes part in a redox reaction.
a) ammonia
b)barium chloride
c)acidified potassium dichromate
d)sodium hydroxide
The answer given is C. Mind explaining the reason, and the other choices? thanks anyone.
dichromate is an oxidizing agent ... it will oxidize iron (II) to iron (III)
when ammonia is added, iron (II) hydroxide is formed, no change in oxidation state of iron
when barium chloride is added, iron(II) chloride is formed, no change in oxidation state of iron
when sodium hydroxide is added, iron (II) hydroxide is formed, no change in oxidation state of iron
hey, thanks alot! I appreciate that =)
hey, some more chemistry questions to consult.
1. 20cm3 of oxygen reacted with 20cm3 of carbon monoxide. what are the volumes of the gases remaining, at the original temp and pressure?
The ans is oxygen-10cm3 carbon monoxide-0cm3 and carbondioxide-30cm3. Why is this so?
2.what has a mass equal to that of one mole of water?
a. 24dm3 of water
b.one mole of steam
c. one molecule of water
d.2 moles of hydrogen molecules and one mole of oxygen molecules.
why is the answer B?
3. What is the mass of aluminium in 204g of aluminium oxide,al2o3(numbers are in sub script)
a.26g
b.27g
c.54g
d.108g
how do i get to the answer d?
1.
O2 + 2CO ---> 2CO2
CO is the limiting reagent.
20cm³ of CO reacts with 10cm³ of O2 to produce 20cm³ of CO2
Remaining gases: 10cm³ of O2 , 20cm³ of CO2
Not sure why the answer stated 30cm³ of CO2
2.
1 mole of water, H2O(l), has a mass of 18g
1 mole of steam, H2O(g), has a mass of 18g
24dm³ of water has a mass of 24000g (density of water = 1g/cm³)
1 molecule of water is equal to 1/(6*10^23) mole of water which does not have a mass of 18g
2 moles of H2 and 1 mole of O2 has a mass of 2*2+32 = 36g
3.
Mass of Al when expressed as a fraction of mass of Al2O3 is (27*2)/(27*2 + 16*3) = 54/102
Mass of Al in 204g of Al2O3 = 54/102 * 204 = 108g
thanks alot wishboy!
Just another one, what do both an atom and an ion of the isotope of sodium contain?
a.11 electrons
b.12neutrons
c.23 protons
d.23 neutrons
The ans is B. I uds that the number of neutrons for the atom is 12 (23-11) but for the ion of the isotope why is it 12 as well. Isn't isotopes contain same number of protons and diff numbers of neutrons?
the answer is B
Originally posted by papery:the answer is B
ignore the pervious post, it is advertising post.