A frying pan is quickly heated on a stovetop to 200 C. It has an iron handle that is 20 cm long . Estimate how much time should pass before the end of the handle is too hot to grab with your bare hand.

Explanation:

Heat = mc(change in temp.)

m=mass , c = specific heat

Rate of flow of heat = heat current = kA/L(T2-T1)

So, mass = density×volume

So, mc(T2-T1)/time =

kA/L(T2-T1)

Substitute the values given as there are a lot of values missing, so the answer can not be obtained.

  the grams     of oxygen gas   that can be produced     is 20.6   grams of o₂

calculation

2liclo₃ →   2 licl + 3 o₂

step 1:   find the moles of liclo₃

moles = mass÷ molar mass

from periodic table the molar mass of liclo₃ =6.9 +35.5   +(16 x3) =90.4 g/mol

moles=38.7 g÷90.4 g/mol=0.4281   moles

step 2:   use the   mole ratio   to calculate the moles of o2

from equation above, liclo₃: o₂   is 2: 3  

therefore the moles of   o₂=0.4281 moles x3/2 =0.6422   moles

step 3: find mass   of o₂

mass= moles x molar mass

from periodic table the   molar mass of   o₂ = 16 x2= 32 g/mol

mass=0.6422   moles   x   32 g/mol = 20.6 grams of o₂

scientific laws are the result of testing theories and proving them to be facts.