Which would be best categorized as heat transfer by convection? noodles rising and falling in a pot of boiling water touching a metal spoon that is sitting in a pot of boiling water using a heating blanket to get warm wearing a white shirt to stay cool on a summer day.

Option (A) is the correct answer.

Explanation:

When a substance is heated then less dense (hotter) material rises and more denser (colder) material sink due to the influence of gravity. As a result, heat transfer form hotter to colder substance and this process is known as convection.

For example, noodles in a hot water. Noddles being more denser (colder) will sink at the bottom and water being less dense will rise.

Thus, we can conclude that out of the given options, noodles rising and falling in a pot of boiling water is best categorized as heat transfer by convection.

as given the equation is

2al + 6 hcl > 2 alcl3 + 3 h2(g)

as per equation two moles of aluminum reacts with six moles of hcl to give two moles of alcl3 and three moles of hydrogen gas

given: three moles of al are present and 7 moles of hcl

for three moles of aluminum nine moles of hcl will be required

however as 7 moles of hcl are present so the limiting reagent is hcl

hcl is going to decide the number of moles of product formed

when six moles of hcl are present = 3 moles of h2 are formed

when one mole of hcl is present == 3/6 mole sof h2 will be formed

when 7 moles of hcl are present = 3 x 7/ 6 moles of h2 will be formed = 3.5 moles of h2