Glenn is heating water in a teakettle. the hotter water at the bottom of the kettle rises. the cooler water near the top sinks and warms. which kind of transfer of heat is this?

conduction
convection
radiation
transmission

Option (b) is the correct answer.

Explanation:

A process in which on heating a fluid (liquid or gas) the hot material (less dense) rises at the top whereas cool material (more dense) sinks at the bottom then this intermixing of materials is known as a convection.

In conduction process, two atoms with different temperature are kept adjacent to each other then heat flows from warmer object to cooler object.

Radiation is the transfer of energy waves which travel through the space. For example, a metal sheet kept under Sun will become warm due to radiations from the Sun.

Transmission is the process of transferring heat from one body to another with the help a medium.

Thus, we can conclude that in the given situation when cooler water near the top sinks and warms then this type of heat transfer is convection.

the answer would be c

  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