Background: A large log placed in a fire will burn relatively slowly. If the same mass of wood were added to the fire in the form of small twigs, they would burn much more quickly. This is because the twigs provide a greater surface area than the log does. An increase in the surface area of a reactant increases the rate of a reaction. Surface area is larger when a given amount of a solid is present as smaller particles. A powdered reactant has a greater surface area than the same reactant as a solid chunk. In order to increase the surface area of a substance, it may be ground into smaller particles or dissolved into a liquid. In solution, the dissolved particles are separated from each other and will react more quickly with other reactants.

Situation: Two friends went camping and made a fire each. Bill used a few large logs while Tim used kindlings, wood chips and sawdust. they both brought the same volume of wood.

Question: Which friend made a fire that burned slower?
Answer: Bill

Situation: Two friends went camping and made a fire each. Bill used a few large logs while Tim used kindlings, wood chips and sawdust. they both brought the same volume of wood.

Question: Which friend didn't make a fire that burned slower?
Answer: Tim

Situation: Two friends went camping and made a fire each. Bill used a few large logs while Tim used kindlings, wood chips and sawdust. they both brought the same volume of wood.

Question: Which friend didn't make a fire that burned faster?
Answer: Bill

Situation: Two friends went camping and made a fire each. Bill used a few large logs while Tim used kindlings, wood chips and sawdust. they both brought the same volume of wood.

Question: Which friend made a fire that burned faster?
Answer: Tim

Situation: Two friends went camping and made a fire each. Bill used a few large logs while Tim used kindlings, wood chips and sawdust. they both brought the same volume of wood.

Question: Which friend made a fire that burned hotter?
Answer: Tim

Situation: Two friends went camping and made a fire each. Bill used a few large logs while Tim used kindlings, wood chips and sawdust. they both brought the same volume of wood.

Question: Which friend made a fire that burned less hot?
Answer: Bill

Situation: Two friends went camping and made a fire each. Bill used a few large logs while Tim used kindlings, wood chips and sawdust. they both brought the same volume of wood.

Question: Which friend provided more wood surface area for the fire to burn?
Answer: Tim

Situation: Two friends went camping and made a fire each. Bill used a few large logs while Tim used kindlings, wood chips and sawdust. they both brought the same volume of wood.

Question: Which friend provided a smaller wood surface area for the fire to burn?
Answer: Bill

Situation: Two friends went camping and made a fire each. Bill used a few large logs while Tim used kindlings, wood chips and sawdust. they both brought the same volume of wood.

Question: Which friend provided conditions for increased reaction rate?
Answer: Tim

Situation: Two friends went camping and made a fire each. Bill used a few large logs while Tim used kindlings, wood chips and sawdust. they both brought the same volume of wood.

Question: Which friend provided conditions for decreased reaction rate?
Answer: Bill

Situation: Two groups of friends went camping , but camped separately afew hundred yards away and started a fire each. Both groups had the same volume of wood. Group P had larger logs, while group Q had small twigs, sawdust and kindlings.

Question: Which group made a fire that burned much slower?
Answer: Group P

Situation: Two groups of friends went camping , but camped separately afew hundred yards away and started a fire each. Both groups had the same volume of wood. Group P had larger logs, while group Q had small twigs, sawdust and kindlings.

Question: Which group didn't make a fire that burned slower?
Answer: group Q

Situation: Two groups of friends went camping , but camped separately a few hundred yards away and started a fire each. Both groups had the same volume of wood. Group P had larger logs, while group Q had small twigs, sawdust and kindlings.

Question: Which group didn't make a fire that burned much more quickly?
Answer: Group P

Situation: Two groups of friends went camping , but camped separately a few hundred yards away and started a fire each. Both groups had the same volume of wood. Group P had larger logs, while group Q had small twigs, sawdust and kindlings.

Question: Which group made a fire that burned much more quickly?
Answer: group Q

Situation: Two groups of friends went camping , but camped separately a few hundred yards away and started a fire each. Both groups had the same volume of wood. Group P had larger logs, while group Q had small twigs, sawdust and kindlings.

Question: Which group had wood that provided a larger surface area for the fire to burn?
Answer: group Q

Situation: Two groups of friends went camping , but camped separately a few hundred yards away and started a fire each. Both groups had the same volume of wood. Group P had larger logs, while group Q had small twigs, sawdust and kindlings.

Question: Which group had wood that provided a smaller surface area for the fire to burn?
Answer: Group P

Situation: Two groups of friends went camping , but camped separately a few hundred yards away and started a fire each. Both groups had the same volume of wood. Group P had larger logs, while group Q had small twigs, sawdust and kindlings.

Question: Which group had brought smaller particles of wood to burn?
Answer: group Q

Situation: Two groups of friends went camping , but camped separately a few hundred yards away and started a fire each. Both groups had the same volume of wood. Group P had larger logs, while group Q had small twigs, sawdust and kindlings.

Question: Which group didn't bring small particles of wood to burn?
Answer: Group P

Situation: Two groups of friends went camping , but camped separately a few hundred yards away and started a fire each. Both groups had the same volume of wood. Group P had larger logs, while group Q had small twigs, sawdust and kindlings.

Question: Which group brought solid chunks of wood?
Answer: Group P

Situation: Two groups of friends went camping , but camped separately a few hundred yards away and started a fire each. Both groups had the same volume of wood. Group P had larger logs, while group Q had small twigs, sawdust and kindlings.

Question: Which group didn't bring solid chunks of wood?
Answer: group Q

Situation: Two groups of scientists examined two fires. Group A put a large log on it, and group B made a fire with small twigs. They wanted to see which fire would last longer.

Question: Which group had a fire that burned faster?
Answer: group B

Situation: Two groups of scientists examined two fires. Group A put a large log on it, and group B made a fire with small twigs. They wanted to see which fire would last longer.

Question: Which group had a fire that burned slower?
Answer: Group A

Situation: Two groups of scientists examined two fires. Group A put a large log on it, and group B made a fire with small twigs. They wanted to see which fire would last longer.

Question: Which group had a fire that lasted longer?
Answer: Group A

Situation: Two groups of scientists examined two fires. Group A put a large log on it, and group B made a fire with small twigs. They wanted to see which fire would last longer.

Question: Which group had a fire that lasted less?
Answer: group B

Situation: Two groups of scientists examined two fires. Group A put a large log on it, and group B made a fire with small twigs. They wanted to see which fire would last longer.

Question: Which group had a fire with wood that provided a greater surface area?
Answer: group B

Situation: Two groups of scientists examined two fires. Group A put a large log on it, and group B made a fire with small twigs. They wanted to see which fire would last longer.

Question: Which group had a fire with wood that provided a smaller surface area?
Answer: Group A

Situation: Two groups of scientists examined two fires. Group A put a large log on it, and group B made a fire with small twigs. They wanted to see which fire would last longer.

Question: Which group had a fire with wood that provoked a more intense reaction?
Answer: group B

Situation: Two groups of scientists examined two fires. Group A put a large log on it, and group B made a fire with small twigs. They wanted to see which fire would last longer.

Question: Which group had a fire with wood that provoked a less intense reaction?
Answer: Group A

Situation: Two groups of scientists examined two fires. Group A put a large log on it, and group B made a fire with small twigs. They wanted to see which fire would last longer.

Question: Which group had a fire with wood made from smaller particles?
Answer: group B

Situation: Two groups of scientists examined two fires. Group A put a large log on it, and group B made a fire with small twigs. They wanted to see which fire would last longer.

Question: Which group had a fire with wood made from bigger chunks?
Answer: Group A

Situation: Danny went camping and made a fire in the woods. he used large logs he fell a few months back. Bob was camping 300 yards away and he made a fire using small sticks, kindlings and sawdust he had left over. Bob's fire burned fast and bright.

Question: Which person made a fire that burned for a longer time?
Answer: Danny

Situation: Danny went camping and made a fire in the woods. he used large logs he fell a few months back. Bob was camping 300 yards away and he made a fire using small sticks, kindlings and sawdust he had left over. Bob's fire burned fast and bright.

Question: Which person didn't make a fire that burned for a longer time?
Answer: Bob

Situation: Danny went camping and made a fire in the woods. he used large logs he fell a few months back. Bob was camping 300 yards away and he made a fire using small sticks, kindlings and sawdust he had left over. Bob's fire burned fast and bright.

Question: Which person didn't make a fire that burned for a shorter time?
Answer: Danny

Situation: Danny went camping and made a fire in the woods. he used large logs he fell a few months back. Bob was camping 300 yards away and he made a fire using small sticks, kindlings and sawdust he had left over. Bob's fire burned fast and bright.

Question: Which person made a fire that burned for a shorter time?
Answer: Bob

Situation: Danny went camping and made a fire in the woods. he used large logs he fell a few months back. Bob was camping 300 yards away and he made a fire using small sticks, kindlings and sawdust he had left over. Bob's fire burned fast and bright.

Question: Which person's wood provided more surface area for the fire to take place ?
Answer: Bob

Situation: Danny went camping and made a fire in the woods. he used large logs he fell a few months back. Bob was camping 300 yards away and he made a fire using small sticks, kindlings and sawdust he had left over. Bob's fire burned fast and bright.

Question: Which person's wood provided less surface area for the fire to take place ?
Answer: Danny

Situation: Danny went camping and made a fire in the woods. he used large logs he fell a few months back. Bob was camping 300 yards away and he made a fire using small sticks, kindlings and sawdust he had left over. Bob's fire burned fast and bright.

Question: Which person made a fire that burned hotter?
Answer: Bob

Situation: Danny went camping and made a fire in the woods. he used large logs he fell a few months back. Bob was camping 300 yards away and he made a fire using small sticks, kindlings and sawdust he had left over. Bob's fire burned fast and bright.

Question: Which person made a fire that burned less hot?
Answer: Danny

Situation: Danny went camping and made a fire in the woods. he used large logs he fell a few months back. Bob was camping 300 yards away and he made a fire using small sticks, kindlings and sawdust he had left over. Bob's fire burned fast and bright.

Question: Which person made a fire that burned brighter?
Answer: Bob

Situation: Danny went camping and made a fire in the woods. he used large logs he fell a few months back. Bob was camping 300 yards away and he made a fire using small sticks, kindlings and sawdust he had left over. Bob's fire burned fast and bright.

Question: Which person made a fire that burned less bright?
Answer: Danny

Situation: Two groups of teens studied fire for the physics class. Group S made a fire using large logs, while group F made a fire using small twigs and sawdust. Both groups used the same volume of wood.

Question: Which group made a fire that burned for a longer time?
Answer: Group S

Situation: Two groups of teens studied fire for the physics class. Group S made a fire using large logs, while group F made a fire using small twigs and sawdust. Both groups used the same volume of wood.

Question: Which group made a fire that burned for a shorter time?
Answer: group F

Situation: Two groups of teens studied fire for the physics class. Group S made a fire using large logs, while group F made a fire using small twigs and sawdust. Both groups used the same volume of wood.

Question: Which group made a fire that burned slower?
Answer: Group S

Situation: Two groups of teens studied fire for the physics class. Group S made a fire using large logs, while group F made a fire using small twigs and sawdust. Both groups used the same volume of wood.

Question: Which group made a fire that burned faster?
Answer: group F

Situation: Two groups of teens studied fire for the physics class. Group S made a fire using large logs, while group F made a fire using small twigs and sawdust. Both groups used the same volume of wood.

Question: Which group made a fire from larger particles?
Answer: Group S

Situation: Two groups of teens studied fire for the physics class. Group S made a fire using large logs, while group F made a fire using small twigs and sawdust. Both groups used the same volume of wood.

Question: Which group made a fire from smaller particles?
Answer: group F

Situation: Two groups of teens studied fire for the physics class. Group S made a fire using large logs, while group F made a fire using small twigs and sawdust. Both groups used the same volume of wood.

Question: Which group made a fire from more particles of wood?
Answer: group F

Situation: Two groups of teens studied fire for the physics class. Group S made a fire using large logs, while group F made a fire using small twigs and sawdust. Both groups used the same volume of wood.

Question: Which group made a fire from fewer particles of wood?
Answer: Group S

Situation: Two groups of teens studied fire for the physics class. Group S made a fire using large logs, while group F made a fire using small twigs and sawdust. Both groups used the same volume of wood.

Question: Which group provided a greater surface area for an increased rate of the burning reaction?
Answer: group F

Situation: Two groups of teens studied fire for the physics class. Group S made a fire using large logs, while group F made a fire using small twigs and sawdust. Both groups used the same volume of wood.

Question: Which group provided a smaller surface area for an increased rate of the burning reaction?
Answer: Group S