Calculate the mass of lead(ll)tetraoxosuplhatevi formed when 0.5mol-¹ of tetraoxosulphate vi when react with lead(ll)chloride

The mass of lead(ll)tetraoxosuplhate formed when 0.5mol-¹ of tetraoxosulphate react with lead(ll)chloride is :

151.63 grams

Explanation:

PbCl2 =  lead(ll)chloride

PbSO4 = lead(ll)tetraoxosuplhate

H2SO4 = hydrogen tetraoxosulphate

HCl = Hydrochloric acid

The balanced equation for the reaction is :

The stoichiometric coefficients indicates that :

1 mole PbCl2 = 1 mole H2SO4 =  1 mole PbSO4 = 2 mole HCl

1 mole H2SO4 produces  = 1 mole PbSO4

0.5 mole produce = 0.5 mole of PbSO4

We have 0.5 mole of PbSO4

So , we are asked to calculate the mass of 0.5 mole pf PbSO4

Molar mass of PbSO4 = mass of Pb + Mass of S + 4(mass of O)

= 207.2 + 32.06 +4(16)

=303.26 grams

151.63 grams

1. the question asks the most appropriate, which seems to rule out "all of the above." your choice appears to be the correct one.

2. the protocol described is good for identifying correlation, but not cause and effect. for cause/effect, you need to devise a protocol that will assign the treatment (or not) to groups that have essentially the same "demographics" with respect to all the other variables. your choice regarding control group seems appropriate. random assignment of treatment (choice d) may be appropriate also. (i think you can argue that b and d are just different descriptions of the same method.)

3. d will randomize the birds, but may not guarantee there are 10 in each group. e will do both, so seems the better choice.

comment on question 2

based on the problem statement, it seems clear that confident, attentive drivers are more likely to use daytime running lights. so, the protocol might need to be devised in such a way that the lights would be turned on or off without the driver's knowledge. (an attentive driver will figure it out.) assigning a confident, attentive driver to a group required to drive without running lights might mess with his/her confidence and attentiveness. you don't want your experiment to do that. (nor do you want the experiment to subject a driver to greater risk of accident as a consequence of driving without running lights.) experiments involving human safety are always problematic.

it should be all of them because it asks if you included all of those in your answer

explanation: